Chapter 44

cotton, sugar, alfalfa and garden vegetables are cultivated; south of the Red river is a peculiarly rich farming country watered by Bayou Rapides and Bayou Boeuf. Near the city is the Louisiana Asylum for the Insane. The principal industaes are cotton- pressing and the manufacture of lumber and of cotton-seed products; sugar and molasses, artificial ice, mineral waters and brick are other manufactures. The city owns and operates the water-works and electric-lighting plant; the water-supply is derived from artesian wells. Alexandria was named in honour of Alexander Fulton, on whose grant from Spain the first settlement was made in 1785; it was first incorporated as a town in 1818 and received a city charter in 1882. In the spring of 1863 a Union fleet under Admiral David D. Porter, operating on the Red river, co-operated with land forces under General N. P. Banks in pushing the Confederates westward. Alexandria was occupied on the 7th of May 1863, but the troops were soon withdrawn for the Port Hudson attack. On the 19th of March 1864 it was again occupied by the Union forces, who made it the point of concentration for another land and naval expedition against E. Kirby Smith and Shreveport. After the check of this expedition and its abandonment, Alexandria was again vacated on the 12th-13th of May, when the city was almost entirely burned. The Union gunboats, which had passed up the river toward Shreveport at high water, were caught in its decline above the falls at Alexandria, but they were saved by a splendid piece of engineering (a dam at the falls), constructed by Lieutenant-Colonel Joseph Bailey (1827-1867), who for this service received the thanks of Congress and the brevet of brigadier-general of volunteers.

ALEXANDRIA, a town of Rumania, situated among the rich corn-lands of the Teleorman department, on the right bank of the river Vedea. Pop. (1900) 13,675. Its chief trade is in grain, despatched by rail to the Danubian port of Zimnicea, or by river to Giurgevo. Alexandria was named after its founder, Alexander John Cuza, prince of Rumania from 1859 to 1866.

ALEXANDRIA, a manufacturing town of Dumbartonshire, Scotland, situated on the right bank of the Leven about 3 m. north of Dumbarton, on the North British and Caledonian railways. It owes its origin almost entirely to the cotton printing and bleaching works of the vicinity, for which there is an abundant supply of excellent water, and contains one of the largest of the Turkey-red dyeing establishments in the Vale of Leven. The public buildings include a public hall, the mechanics' institute with library and lecture-hall, an institute for men, with library and recreation rooms, a similar institution for women, banks and other important commercial offices. Pop. (1891) 7796; (1901) 8007. Alexandria is connected with BONHILL, on the opposite bank of the river, by a bridge which replaced in 1898 one bought three years earlier by the county council from the Smollett family, who have been closely associated with the district since the time of Sir James Smollett, the novelist's grandfather. The industries of Bonhill centre in the calico printing, dyeing and bleaching which find their headquarters in the valley. Population (1891) 3843; (1901) 3333. JAMESTOWN, about 1 m. to the north-east of Alexandria, with a station on the Forth & Clyde railway from Balloch to Stirling (North British), contains some of the largest cotton-printing works in Scotland. Population (1891) 1668; (1901) 2080.

ALEXANDRIA, a city and a port of entry of Alexandria county, Virginia, U.S.A., on the W. bank of the Potomac river, 6 m. below Washington, D.C., with which it is connected by a ferry. Pop. (1890) 14,339; (1900) 14,528, of whom 4533 were negroes; (1910, census), 15,329. Alexandria is served by the Baltimore & Ohio, the Chesapeake & Ohio, the Southern and the Washington Southern railways; by the Washington, Alexandria & Mount Vernon electric railway; and by several lines of river and coasting steamboats. It is a quaint, old-fashioned city, with quiet, shady streets, and a number of buildings dating back to the 18th century; of these the most interesting is the old Christ Church in which George Washington and Robert E. Lee worshipped. The city has a public library. About 2 1/2 m. W. of Alexandria is the Protestant Episcopal Theological Seminary in Virginia, opened here in 1823 and chartered in 1854; in 1906-1907 the Seminary had a faculty of 7 and 46 students. Alexandria is a distributing and jobbing centre for the north-east counties of Virginia. Among its manufactures are fertilizers, bottles, carbonated beverages, flour, beer, shoes, silk thread, aprons, brooms, leather, bricks, and tiling and structural iron. The total value of its factory product in 1905 was $2,186,658. The municipality owns and operates its gas-lighting plant. Alexandria, first known as Belhaven, was named in honour of John Alexander, who in the last quarter of the 17th century had bought the land on which the city now stands from Robert Howison; the first settlement here was made in 1695. Alexandria was laid out in 1749 and was incorporated in 1779. From 1790 until 1846 Alexandria county was a part of the District of Columbia; at present the city, although within the limits of Alexandria county, is not administratively a part of it. The city was re-chartered in 1852. For some time Alexandria seemed destined to become an important commercial centre, but the rise of Washington created a rival that soon outstripped it, and since the Civil War the city's growth has been comparatively slight. At Alexandria in 1755 General Edward Braddock organized his fatal expedition against Fort Duquesne, and here, in April of the same year, the governors of Virginia, Massachusetts, New Yfork, Pennsylvania and Maryland met (in a house still standing) to determine upon concerted action against the French in America. In March 1785 commissioners from Virginia and Maryland met here to discuss the commercial relations of the two states, finishing their business at Mount Vernon on the 28th with an agreement for freedom of trade and freedom of navigation of the Potomac. The Maryland legislature in ratifying this agreement on the 22nd of November proposed a conference between representatives from all the states to consider the adoption of definite commercial regulations. This led to the calling of the Annapolis convention of 1786, which in turn led to the calling of the Federal convention of 1787. In 1814 Alexandria was threatened by a British fleet, but bought immunity from attack by paying about $100,000. At the opening of the Civil War the city was occupied by Federal troops, and great excitement throughout the North was caused by the killing (May 24, 1861) of Colonel E. E. Ellsworth (1837-1861) by Captain James W. Jackson, a hotel proprietor, from whose building Ellsworth had removed a Confederate flag. After the erection of the state of West Virginia (1863), and until the close of the war, Alexandria was the seat of what was known as the ``Alexandria Government'' (see VIRGINIA).

ALEXANDRIAN SCHOOL. Under this title are generally included certain strongly marked tendencies in literature, science and art, which took their rise in the ancient Egyptian city of Alexandria. That city, founded by Alexander the Great about the time when Greece, in losing her national independence, lost also her intellectual supremacy, was in every way admirably adapted for becoming the new centre of the world's activity and thought. Its situation brought it into commercial relations with all the nations lying around the Mediterranean, and at the same time rendered it the one communicating link with the wealth and civilization of the East. The great natural advantages it thus enjoyed were artificially increased to an enormous extent by the care of the sovereigns of Egypt. Ptolemy Soter (reigned 323-285 B.C.), to whom, in the general distribution of Alexander's conquests, this kingdom had fallen, began to draw around him from various parts of Greece a circle of men eminent in literature and philosophy. To these he gave every facility for the prosecution of their learned researches. Under the inspiration of his friend Demetrius of Phalerum, the Athenian orator, statesman and philosopher, this Ptolemy laid the foundations of the great Alexandrian library and originated the keen search for all written works, which resulted in the formation of a collection such as the world has seldom seen. He also built, for the convenience of his men of letters, the Museum, in which, maintained by the royal bounty, they resided, studied and taught. This Museum, or academy of science, was in many respects not unlike a modern university. The work thus begun by Ptolemy Soter was carried on vigorously by his descendants, in particular by his two immediate successors, Ptolemy Philadelphus and Ptolemy Euergetes. Philadelphus (285-247), whose librarian was the celebrated Callimachus, bought up all Aristotle's collection of books, and also introduced a number of Jewish and Egyptian works. Among these appears to have been a portion pf the Septuagint. Euergetes (247-222) largely increased the library by seizing on the original editions of the dramatists laid up in the Athenian archives, and by compelling all travellers who arrived in Alexandria to leave a copy of any work they possessed.

The intellectual movement so originated extended over a long period of years. If we date its rise from the 4th century B.C., at the time of the fall of Greece and the foundation of the Graeco- Macedonian empire, we must look for its final dissolution in the 7th century of the Christian era, at the time of the fall of Alexandria and the rise of the Mahommedan power. But this very long period falls into two divisions. The first, extending from about 306 to 30, includes the time from the foundation of the Ptolemaic dynasty to its final subjugation by the Romans; the second extends from 30 to A.D. 642, when Alexandria was destroyed by the Arabs. The characteristic features of these divisions are very clearly marked, and their difference affords an explanation of the variety and vagueness of meaning attaching to the term ``Alexandrian School.'' In the first of the two periods the intellectual activity was of a purely literary and scientific nature. It was an attempt to continue and develop, under new conditions, the old Hellenic culture. This direction of effort was particularly noticeable under the early Ptolemies, Alexandria being then almost the only home in the world for pure literature. During the last century and a half before the Christian era, the school, as it might be called, began to break up and to lose its individuality. This was due partly to the state of government under some of the later Ptolemies, partly to the formation of new literary circles in Rhodes, Syria and elsewhere, whose supporters, though retaining the Alexandrian peculiarities, could scarcely be included in the Alexandrian school. The loss of active life, consequent on this gradual dissolution, was much increased when Alexandria fell under Roman sway. Then the influence of the school was extended over the whole known world, but men of letters began to concentrate at Rome rather than at Alexandria. In that city, however, there were new forces in operation which produced a second grand outburst of intellectual life. The new movement was not in the old direction--had, indeed, nothing in common with it. With its character largely determined by Jewish elements, and even more by contact with the dogmas of Christianity, this second Alexandrian school resulted in the speculative philosophy of the Neo-Platonists and the religious philosophy of the Gnostics and early church fathers.

There appear, therefore, to be at least two definite significations of the title Alexandrian School; or rather, there are two Alexandrian schools, distinct both chronologically and in substance. The one is the Alexandrian school of poetry and science, the other the Alexandrian school of philosophy. The term ``school,'' however, has not the same meaning as when applied to the Academics or Peripatetics, the Stoics or Epicureans. These consisted of a company united by holding in common certain speculative principles, by having the same theory of things. There was nothing at all corresponding to this among the Alexandrians. In literature their activities were directed to the most diverse objects; they have only in common a certain spirit or form. There was among them no definite system of phllosophy. Even in the later schools of philosophy proper there is found a community rather of tendency than of definite result or of fixed principles.

I. Literature.--The general character of the literature of the school appears as the necessary consequence of the state of affairs brought about by the fall of Greek nationality and independence. The great works of the Greek mind had formerly been the products of a fresh life of nature and perfect freedom of thought. All their hymns, epics and histories were bound up with their individuality as a free people. But the Macedonian conquest at Chaeroneia brought about a complete dissolution of this Greek life in all its relations, private and political. The full, genial spirit of Greek thought vanished when freedom, with which it was inseparably united, was lost. A substitute for this originality was found at Alexandria in learned research, extended and multifarious knowledge. Amply provided with means for acquiring information, and under the watchful care of a great monarch, the Alexandrians readily took this new direction in literature. With all the great objects removed which could excite a true spirit of poetry, they devoted themselves to minute researches in all sciences subordinate to literature proper. They studied criticism, grammar, prosody and metre, antiquities and mythology. The results of this study constantly appear in their productions. Their works are never national, never addressed to a people, but to a circle of learned men. Moreover, the very fact of being under the protection and, as it were, in the pay of an absolute monarch was damaging to the character of their literature. There was introduced into it a courtjy element, clear traces of which, with all its accompaniments, are found in the extant works of the school. One other fact, not to be forgotten in forming a general estimate of the literary value of their productions, is, that the same writer was frequently or almost always distinguished in several special sciences. The most renowned poets were at the same time men of culture and science, critics, archaeologists, astronomers or physicians. To such writers the poetical form was merely a convenient vehicle for the exposition of science.

The forms of poetical composition chiefly cultivated by the Alexandrians were epic and lyric, or elegiac. Great epics are wanting; but in their place, as might almost have been expected, are found the historical and the didactic or expository epics. The subjects of the historical epics were generally some of the well-known myths, in the exposition of which the writer could exhibit the full extent of his learning and his perfect command of verse. These poems are in a sense valuable as repertoires of antiquities; but their style is on the whole bad, and infinite patience is required to clear up their numerous and obscure allusions. The best extant specimen is the Argonautica of Apollonius Rhodius; the most characteristic is the Alexandra or Cassandra of Lycophron, the obscurity of which is almost proverbial.

The subjects of didactic epics were very numerous; they seem to have depended on the special knowledge possessed by the writers, who used verse as a form for unfolding their information. Some, e.g. the lost poem of Callimachus, called Ai'tia, were on the origin of myths and religious observances; others were on special sciences. Thus we have two poems of Aratus, who, though not resident at Alexandria, was so thoroughly imbued with the Alexandrian spirit as to be with reason included in the school; the one is an essay on astronomy, the other an account of the signs of the weather. Nicander of Colophon has also left us two epics, one on remedies for poisons, the other on the bites of venomous beasts. Euphorion and Rhianus wrote mythological epics. The spirit of all their productions is the same, that of learned research. They are distinguished by artistic form, purity of expression and strict attention to the laws of metre and prosody, qualities which, however good in themselves, do not compensate for want of originality, freshness and power.

In their lyric and elegiac poetry there is much worthy of admiration. The specimens we possess are not devoid of talent or of a certain happy art of expression. Yet, for the most part, they either relate to objects thoroughly incapable of poetic treatment, where the writer's endeavour is rather to expound the matter fully than to render it poetically beautiful, or else expend themselves on short isolated subjects, generally myths, and are erotic in character. The earliest of the elegiac poets was Philetas, the sweet singer of Cos. But the most distinguished was Callimachus, undoubtedly the greatest of the Alexandrian poets. Of his numerous works there remain to us only a few hymns, epigrams and fragments of elegies.1 Other lyric poets were Phanocles, Hermesianax, Alexander of Aetolla and Lycophron.

Some of the best productions of the school were their epirams. Of these we have several specimens, and the art of composing them seems to have been assiduously cultivated, as might naturally be expected from the court life of the poets, and their constant endeavours after terseness and neatness of expression. Of kindred character were the parodies and satirical poems, of which the best examples were the Silli of Timon and the Cinaedi of Sotades.

Dramatic poetry appears to have flourished to some extent. There are still extant three or four varying lists of the seven great dramatists who composed the Pleiad of Alexandria. Their works, perhaps not unfortunately, have perished. A ruder kind of drama, the amoebaean verse, or bucolic mime, developed into the only pure stream of genial poetry found in the Alexandrian School, the Idylls of Theocritus. The name of these poems preserves their original idea; they were pictures of fresh country life.

The most interesting fact connected with this Alexandrian poetry is the powerful influence it exercised on Roman literature. That literature, especially in the Augustan age, is not to be thoroughly understood without due appreciation of the character of the Alexandrian school. The historians of this period were numerous and prolific. Many of them, e.g. Cleitarchus, devoted themselves to the life and achievements of Alexander the Great. The best-known names are those of Timaeus and Polybius.

Before the Alexandrians had begun to produce original works, their researches were directed towards the masterpieces of ancient Greek literature. If that literature was to be a power in the world, it must be handed down to posterity in a form capable of being understood. This was the task begun and carried out by the Alexandrian critics. These men did not merely collect works, but sought to arrange them, to subject the texts to criticism, and to explain any allusion or reference in them which at a later date might become obscure. The complete philological examination of any work consisted, according to them, of the following processes:---diorthosis, arrangement of the text; anagnosis, settlement of accents; tenn??, theory of forms, syntax; lxegnsis, explanation either of words or things; and finally, krisis, judgment on the author and his work, including all questions as to authenticity and integrity. To perform their task adequately required from the critics a wide circle of knowledge; and from this requirement sprang the sciences of grammar, prosody, lexicography, mythology and archaeology. The service rendered by these critics is invaluable. To them we owe not merely the possession of the greatest works of Greek intellect, but the possession of them in a readable state. The most celebrated critics were Zenodotus; Aristophanes of Byzantium, to whom we owe the theory of Greek accents; Crates of Mallus; and Aristarchus of Samothrace, confessedly the coryphaeus of criticism. Others were Lycophron, Callimachus, Eratosthenes and many of a later age, for the critical school long survived the literary. Dionysius Thrax, the author of the first scientific Greek grammar, may also be mentioned. These philological labours were of great indirect importance, for they led immediately to the study of the natural sciences, and in particular to a more accurate knowledge of geography and history. Considerable attention began to be paid to the ancient history of Greece, and to all the myths relating to the foundation of states and cities. A large collection of such curious information is contained in the Bibliotheca of Apollodorus, a pupil of Aristarchus who flourished in the 2nd century B.C. Eratosthenes was the first to write on mathematical and physical geography; he also first attempted to draw up a chronological table of the Egyptian kings and of the historical events of Greece. The sciences of mathematics, astronomy and medicine were also cultivated with assiduity and success at Alexandria, but they can scarcely be said to have their origin there, or in any strict sense to form a part of the peculiarly Alexandrian literature. The founder of the mathematical school was the celebrated Euclid (Eucleides); among its scholars were Archimedes; Apollonius of Perga, author of a treatise on Conic Sections; Eratosthenes, to whom we owe the first measurement of the earth; and Hipparchus, the founder of the epicyclical theory of the heavens, afterwards called the Ptolemaic system, from its most famous expositor, Claudius Ptolemaeus. Alexandria continued to be celebrated as a school of mathematics and science long after the Christian era. The science of medicine had distinguished representatives in Herophilus and Erasistratus, the two first great anatomists.

AUTHORITIES.--Muller and Donaldson, History of the Literature of Ancient Greece; W. Christ, Geschichte der griechischen Litteratur; Mahaffy, Greek Life and Thought from the Age of Alexander to the Roman Empire; Couat, La Poesie alexandrine; and especially Susemihl, Geschichte der griechischen Litteratur in der Alexandninerzeit. Nicolai's Gricchische Literaturgeschichte, though somewhat out of date, is useful for bibliography.

II. Philosophy.--Although it is not possible to divide literatures with absolute rigidity by centuries, and although the intellectual life of Alexandria, particularly as applied to science, long survived the Roman conquest, yet at that period the school, which for some time had been gradually breaking up, seems finally to have succumbed. The later productions in the field of pure literature bear the stamp of Rome rather than of Alexandria. But in that city for some time past there had been various forces secretly working, and these, coming in contact with great spiritual changes in the world around, produced a second outburst of intellectual activity, which is generally known as the Alexandrian school of philosophy. The doctrines of this school were a fusion of Eastern and Western thought, and combined in varying proportions the elements of Hellenistic and Jewish philosophy. Traces of this eclectic tendency are discoverable as far back as 280 B.C., but for practical purposes the dates of the school may be given as from about 30 B.C. to A.D. 529. The city of Alexandria had gradually become the neutral ground of Europe, Asia and Africa. Its population, then as at the present day, was a heterogeneous collection of all races. Alexander had planted a colony of Jews who had increased in number until at the beginning of the Christian era they occupied two-fifths of the city and held some of the highest offices. The contact of Jewish theology with Greek speculation became the great problem of thought. The Jewish ideas of divine authority and their transcendental theories of conduct were peculiarly attractive to the Greek thinkers who found no inspiration in the dry intellectualism into which they had fallen (see NEO-PYTHAGOREANISM). At the same time the Jews of the Dispersion had to some extent shaken off the exclusiveness of their old political relations and were prepared to compare and contrast their old territorial theology with cosmopolitan culture. Further, when the two sides came to consider the results of their intellectual inheritance they found that they had sufficient common ground for the initial compromise. Thus the Hellenistic doctrine of personal revelation could be combined with the Jewish tradition of a complete theology revealed to a special people. The result was the application of a purely philosophical system to the somewhat vague and unorganized corpus of Jewish theology. The matter was Jewish, the arrangement Greek. According to the relative predominance of these two elements arose Gnosticism, the Patristic theology, and the philosophical schools of Neo-Pythagoreanism, Neo-Platonism and eclectic Platonism.

The members of the school may be enumerated under three heads. (1) The beginnings of the eclectic spirit are, according to some authorities, discernible in the Septuagint (280 B.C.) (see Frankel, Historisch-kritische Studien zur Septuaginta, 1841), but the first concrete exemplification is found in Aristobulus (e. 160 B.C.). So far as the Jewish succession is concerned, the great name is that of Philo in the first century of our era. He took Greek metaphysical theories, and, by the allegorical method, interpreted them in accordance with the Jewish Revelation. He dealt with (a) human life as explained by the relative nature of Man and God, (b) the Divine nature and the existence of God, and, (c) the great Logos doctrine as the explanation of the relation between God and the material universe. From these three arguments he developed an elaborate theosophy which was a syncretism of oriental mysticism and pure Greek metaphysic, and may be regarded as representing the climax of Jewish philosophy. (2) The first purely philosophical phenomenon of the Alexandrian school was Neo-Pythagoreanism, the second and last Neo-Platonism. Leaving all detailed descriptions of these schools to special articles devoted to them, it is sufficient here to say that their doctrines were a synthesis of Platonism, Stoicism and the later Aristotelianism with a leaven of oriental mysticism which gradually became more and more important. The world to which they spoke had begun to demand a doctrine of salvation to satisfy the human soul. They endeavoured to deal with the problem of good and evil. They therefore devoted themselves to examining the nature of the soul, and taught that its freedom consists in communion with God, to be achieved by absorption in a sort of ecstatic trance. This doctrine reaches its height in Plotinus, after whom it degenerated into magic and theurgy in its unsuccessful combat with the victorious Christianity. Finally this pagan theosophy was driven from Alexandria back to Athens under Plutarch and Proclus, and occupied itself largely in purely historical work based mainly on the attempt to re-organize ancient philosophy in conformity with the system of Plotinus. This school ended under Damascius when Justinian closed the Athenian schools (A.D. 529). (3) The eddies of Neo-Platonism had a considerable effect on certain Christian thinkers about the beginning of the 3rd century. Among these the most important were Clement of Alexandria and Origen. Clement, as a scholar and a theologian, proposed to unite the mysticism of Neo- Platonism with the practical spirit of Christianity. He combined the principle of pure living with that of free thinking, and held that instruction must have regard to the mental capacity of the hearer. The compatibility of Christian and later Neo-Platonic ideas is evidenced by the writings of Synesius, bishop of Ptolemais, and though Neo-Platonism eventually succumbed to Christianity, it had the effect, through the writings of Clement and Origen, of modifying the tyrannical fanaticism and ultra- dogmatism of the early Christian writers.

AUTHORITIES.--Matter, Histoire de l'ecole d'Alexandrie, 2nd ed. (3 vols., 1840-1844); Simon, Histoire de L'ecole d'Ajexandrie (2 vols., 1844-1845); Vacherot, Histoire critique de l'ecole d'Ajexandrie (3 vols., 1846-1851); Kingsley, Alexandria and her Schools (1854); Gfrorer, Philo und die Alexandrinische Theosophie (1835) Dahne, Geschict. Darstellung der Judisch-Alexandrinischen Religionsphilosophie (1834); Histories of Philosophy by Zeller, Uberweg, Windelband, &c., and Bibliography of CHURCH HISTORY, &c.

1 A considerable fragment of his epic Hecale has been discovered in the Rainer papyrus.

ALEXANDRIA TROAS (mod. Eski Stambul), an ancient Greek city of the Troad, situated on the west coast at nearly its middle point, a little south of Tenedos. It was built by Antigonus, perhaps about 310 B.C., and was called by him Antigonia Troas. Early in the next century the name was changed by Lysimachus to Alexandria Troas, in honour of Alexander's memory. As the chief port of north-west Asia Minor, the place prospered greatly in Roman times, and the existing remains sufficiently attest its former importance. Thence St Paul sailed for Europe for the first time, and there occurred later the episode of the raising of Eutychus (Acts xx. 5-12). The site is now covered with valonia oaks, and has been much plundered, e.g by Mahommed IV., who took columns to adorn his new Valideh mosque in Stambul; but the circuit of the old walls can be traced, and in several places they are fairly well preserved. They had a circumference of about six English miles, and were fortified with towers at regular intervals. Remains of some ancient buildings, including a bath and gymnasium, can be traced within this area. Trajan built an aqueduct which can still be traced. The harbour had two large basins, now almost choked with sand. A Roman colony was sent to the place, as Strabo mentions, in the reign of Augustus. The abridged name ``Troas'' (Acts xvi. 8) was probably the current one in later Roman times. (D. G. H.)

ALEXANDRINE VERSE, a name given to the leading measure in French poetry. It is the heroic French verse, used in epic narrative, in tragedy and in the higher comedy. There is some doubt as to the origin of the name; but most probably it is derived from a collection of romances, collected in the 12th century, of which Alexander of Macedon was the hero, and in which he was represented, somewhat like the British Arthur, as the pride and crown of chivalry. Before the publication of this work most of the trouvere romances appeared in octosyllabic verse. There is also a theory that the form was invented by a poet named Alexander. The new work, which was henceforth to set the fashion to French literature, was written in lines of twelve syllables, but with a freedom of pause which was afterwards greatly curtailed. The new fashion, however, was not adopted all at once. The metre fell into disuse until the reign of Francis I., when it was revived by Jean Antoine de Baif, one of the seven poets known as the Pleiades. Jodelle mingled episodical Alexandrines with the vers communs of his tragedies and so introduced them into drama. It was Ronsard, however, who made the verse popular, and gave it vogue in France. From his time it became the recognized vehicle for all great poetry, and the regulation of its pauses became more and more strict. The following is an example of the verse as used by Racine-- Ou suis-je? qu'ai-je fait? || que dois-je faire encore? Quel transport me saisit? || quel chagrin me devore? Two inexorable laws came to be established with regard to the pauses. The first is, that each line should be divided into two equal parts, the sixth syllable always ending with a word. In the earlier use of this metre, on the contrary, it frequently happened that the sixth and seventh syllables belonged to the same word. The other is that, except under the most stringent conditions, there should be none of what the French critics call enjambement, that is, the overlapping of the sense from one line on to the next. Ronsard completely ignored this rule, which was after his time settled by the authority of Malherbe. The latest school of French prosody has given great attention to the breaking up of the Alexandrine, which no longer possesses the rigidity of authoritative form which it held until about 1880, but is often used with a licence no less than when Ronsard wrote.

Michael Drayton, who was twenty-two years of age when Ronsard died, seemed to think that the Alexandrine might be as pleasing to English as it was to French ears, and in this metre he wrote a long poem in twenty-four books called the Polyolbion. The metre, however, failed to catch the English ear. The principal English measure is a line of ten syllables, and the Alexandrine is used only occasionally to give it variety and weight. In ordinary English heroic verse it is but rarely introduced; but in the favourite narrative metre, known as the Spenserian, it comes in regularly as the concluding line of each stanza. In English usage, moreover, it is to be observed that there is no fixed rule as to the position of the pause, though it is true that most commonly the pause occurs at the end of the sixth syllable. Spenser is very free in shifting the pause about; and though the later poets who have used this stanza are not so free, yet, with the exception of Shenstone and of Byron, they do not scruple to obliterate all pause between the sixth and seventh syllables. Thus Thomson (Castle of Indolenee, i. 42):--

And music lent new gladness to the morning air.

The danger in the use of the Alexandrine is that, in attempting to give dignity to his line, the poet may only produce heaviness, incurring the sneer of Pope--

A needless Alexandrine ends the song. That, like a wounded snake, drags its slow length along. The Alexandrine was the dominant metre in Dutch poetry from the 16th to the middle of the 19th century, and about the time of its introduction to Holland it was accepted in Germany by the school of Opitz. In the course of the 17th century, after being used without rhyme by Seckendorf and others, it formed a transitional station on the route to German blank verse, and has since then been rarely employed, except occasionally in rhymed comedy.

ALEXANDRISTS, the name given to those philosophers of the Renaissance, who, in the great controversy on the subject of personal immortality, adopted the explanation of the De Anima given by Alexander of Aphrodisias. According to the orthodox Thomism of the Roman Catholic Church, Aristotle rightly regarded reason as a facility of the individual soul. Against this, the Averroists, led by Agostino Nito (q.v.), introduced the modifying theory that universal reason in a sense individualizes itself in each soul and then absorbs the active reason into itself again. These two theories respectively evolved the doctrine of individual and universal immortality, or the absorption of the individual into the eternal One. The Alexandrists, led by Pietro Pomponazzi, boldly assailed these beliefs and denied that either was rightly attributed to Aristotle. They held that Aristotle considered the soul as a material and therefore a mortal entity which operates during life only under the authority of universal reason. Hence the Alexandrists denied the possibillty of immortality in every shape or form. Since the soul is organically connected with the body, the dissolution of the latter involves the extinction of the former.

ALEXANDRITE, a variety of chrysoberyl (q.v.) discovered in the Urals in 1833, on the day set apart for celebrating the majority of the cesarevich, afterwards the tsar, Alexander II., in whose honour the stone was named by Nils Gustaf Nordenskiold, of Helsingfors. It is remarkable for being strongly dichroic, generally appearing dark green by daylight and raspberry-red by candle-light, or by daylight transmitted through the stone. As red and green are the military colours of Russia, the mineral became highly popular as a gem-stone. The dark green crystals are usually cloudy and cracked, and grouped in triplets presenting a pseudo-hexagonal form. Alexandrite was found originally in the emerald- mine of Takovaya, east of Ekaterinburg in the Urals, and afterwards in the gold-bearing sands of the Sanarka in the southern Urals. Subsequently it was discovered in greater abundance in the gem-gravels of Ceylon. It has been found also in Tasmania. Some of the Ceylon alexandrite exhibits, when suitably cut, the Cat's-eye chatoyance, whence it has been called alexandrite cat's-eye. (F. W. R.*)

ALEXANDROPOL, or ALEXANDRAPOL. (Turk. Gumri), a Russian town and fortified camp in Transcaucasia, government of Erivan, near the junction of the Arpa-chai with the Aras, 48 m. by rail E.N.E. of Kars. Altitude 5080 ft. It has a trade in silk. Here the Russians defeated the Turks in 1853. Pop. (1885) 22,670; (1897) 32,735.

ALEXANDROVSK. (1) A town of N. Russia, in the government of Archangel, on the harbour of Catherine (Ekaterininsk), on the Murman coast, 5 m. from the mouth of Kola Bay. It was opened in 1899 and is a naval station, being free from ice all the year round. It is also called Port Catherine. Pop. (1901) 300. (2) A town of S. Russia, 83 m. S. of Ekaterinoslav, on the railway to the Crimea, near the left bank of the Dnieper, below its rapids. Pop. (1897) 16,393. Opposite it is the island of Khortitsa, upon which was the sich (or syech) or camp of the Zaporozhian cossacks. All its neighbouthood is strewn with kurgans (tumuli).

ALEXIS, Greek comic poet of the Middle Comedy, was born about 394 B.C. at Thurii and taken early to Athens, where he became a citizen. Plutarch says that he lived to the age of 106, and that he died on the stage while being crowned. According to Suidas, who calls him Monander's uncle, he wrote 245 comedies, of which some 130 titles are preserved. The fragments (about 1000 lines) attest the wit and refinement of the author (Koch, Comicorum Atticorum Fragmenta).

ALEXIS, WILLIBALD, the pseudonym of GEORG WILHELM HEINRICH HARING (1798--1871), German historical novelist. He was born on the 29th of June 1798 at Breslau, where his father, who came of a French refugee family, named Hareng, held a high position in the war department. He attended the Werdersche Gymnasium in Berlin, and then, serving as a volunteer in the campaign of 1815, took part in the siege of the Ardenne fortresses. On his return he studied law at the universities of Berlin and Breslau and entered the legal profession, but he soon abandoned this career and devoted himself to literature. Settling in Berlin he edited, 1827-1835, the Berliner Konversationsblatt, in which for the first two years he was assisted by Friedrich Christoph Forster (1791--1868); and in 1828 was created a doctor of philosophy by the university of Halle. In 1852 he retired to Arnstadt in Thuringia, where after many years of broken health he died on the 16th of December 1871.

Haring made his name first known as a writer by an idyll in hexameters, Die Treibjagd (1820), and several short stories in which the influence of Tieck is observable; but his literary reputation was first established by the historical romance Walladmor (1823), which, published as being ``freely translated from the English of Sir Walter Scott, with a preface by Willibald Alexis,'' so closely imitated the style of the famous Scotsman as really to deceive even Scott's admirers. The work became immediately popular and was translated into several languages, including English. It was followed by Schloss Avalon (1827), with regard to which the author adopted the same tactics and with equal success. These historical novels, however, were of considerable literary merit, and would doubtless have achieved popularity even without the borrowed plumage. Soon afterwards Haring published a number of successful short stories (Gesammelte Novellen, 4 vols., 1830-1831), some books of travel, and in the novels Das Haus Dusterweg (1835) and Zwolf Nachte (1838) showed for a while a leaning towards the ``Young German'' school. In Cabanis (1832), however, a story of the time of Frederick the Great, he entered the field of patriotic- historical romance, in which he so far excelled as to have earned the name of ``der Markische Walter Scott'' (Walter Scott of the Mark). From 1840 onwards he published at short intervals a series of romances, each dealing with some epoch in the history of Brandenburg. Among them may be especially noted Der Roland von Berlin (1840), Der falsche Woldemar (1842), Die Hosen des Herrn von Bredow (1846-1848), Ruhe ist die erste Burgerpflicht (1852), Isegrimm (1854) and Dorothe (1856). In all these the author shows himself as a keen observer of men and things; the characters, situations and natural surroundings are excellently delineated, and the patriotic feeling which pervades them is not overdone. Haring also made a name for himself in the field of criminology by commencing in 1842, in conjunction with the publicist, Julius Eduard Hitzig (1780- 1849), the publication of Der neue Pitaval (continued by A. Vollert, 36 vols., Leipzig, 1842-1865; new edition, 24 vols., Leipzig, 1866-1891), a, collection of criminal anecdotes culled from all nations and all times. This publication attained great popularity, and is to-day of psychological interest and value.

His Gesammelte Werke were published in 20 volumes (Berlin, 1874); the Vaterlandische Romane separately in 8 volumes (Berlin, 1881, 1884), and, since the expiry of the copyright in 1901, in many cheap reprints. Cp. W. Alexis' Erinnerungen, edited by M. Ewert (1900), and essays by Julian Schmidt (Neue Bilaer aus dere geistigen Leben unsrer Zeit, 1873), G. Freytag (Werke, vols. 16 and 23), A. Stern Zur Literatur der Gegenwart, 1880) and T. Fontane (in Bayreuther Blatter, vi., 1883).

ALEXISBAD, a spa of Germany, in the duchy of Anhalt, lying under the Harz mountains, 1000 ft. above the sea, on the railway from Gernrode to Harzgerode. Pop. 1000. It is celebrated for its medicinal waters, of which the Abexisbrunnen, a ferruginous spring, is used for drinking, while the Selkebrunnen supplies the baths, which are of use in feminine disorders. The place was founded in 1810 by Duke Alexius of Anhalt-Bernburg.

ALEXIUS I. (1048-1118), emperor of the East, was the third son of John Comnenus, nephew of Isaac Comnenus, emperor 1057-1059. His father declined the throne on the abdication of Isaac, who was accordingly succeeded by four emperors of other families between that date and 1081. Under one of these emperors, Romanus Diogenes (1067-1071), he served with distinction against the Seljuk Turks. Under Michael Parapinaces (1071-1078) and Nicephorus Botaniates (1078-1081) he was also employed, along with his elder brother Isaac, against rebels in Asia Minor, Thrace and in Epirus (1071). The success of the Comneni roused the jealousy of Botaniates and his ministers, and the Comneni were almost compelled to take up arms in self- defence. Botaniates was forced to abdicate and retire to a monastery, and Isaac declined the crown in favour of his younger brother Alexius, who then became emperor in the 33rd year of his age. His long reign of nearly 37 years was full of difficulties (see ROMAN EMPIRE, LATER). At the very outset he had to meet the formidable attack of the Normans (Robert Guiscard and his son Bohemund), who took Dyrrhachium and Corfu, and laid siege to Larissa in Thessaly. The Norman danger ended for the time with Robert Guiscard's death (1085) and the conquests were recovered. He had next to repel the invasions of Patzinaks (Petchenegs) and Kumans in Thrace, with whom the Manichaean sects of the Paulicians and Bogomilians made Common cause; and thirdly, he had to cope with the fast-growing power of the Turks in Asia Minor. Above all he had to meet the difficulties caused by the arrival of the warriors of the First Crusade, which had been in a great degree initiated owing to the representations of his own ambassadors, though the help which he wanted from the West was simply mercenary forces and not the immense hosts which arrived to his consternation and embarrassment. The first part, under Peter the Hermit, he got rid of by sending them on to Asia Minor, where they were massacred by the Turks (1096). The second and much more serious host of warriors, led by Godfrey of Bouillon, he conducted also into Asia, promising to supply them with provisions in return for an oath of homage, and by their victories recovered for the Empire a number of important cities and islands--Nicaea, Chics, Rhodes, Smyrna, Ephesus, Philadelphia, Sardis, and in fact most of Asia Minor (1097-1099). This is ascribed as a credit to his policy and diplomacy by his daughter, by the Latin historians of the crusade to his treachery and falseness, but during the last twenty years of his life he lost much of his popularity. They were marked by persecution of the followers of the Paulician and Bogomilian heresies (one of his last acts was to burn Basilius, a Bogomilian leader, with whom he had engaged in a theological controversy), by renewed struggles with the Turks (1110-1117), by anxieties as to the succession, which his wife Irene wished to alter in favour of her daughter Anne's husband, Nicephorus Bryennius for whose benefit the special title panhypersebastos (i.e. as it were dugustissimus si quis ahus) was created. This intrigue disturbed even his dying hours. He deserves the credit of having raised the Empire from a condition of anarchy and decay at a time when it was threatened on all sides by new dangers. No emperor devoted himself more laboriously or with a greater sense of duty to the task of ruling.

AUTHORITIES.--Zonaras xviii. 27-29; Anna Comnena's Life; see also Du Cange, Familiae Byzantinae; Friedrich Wilken, Rerum ab Alexio I., Joanne, Manuele et Alexio II. Comnenis Romanorum, Byzantinorum imperatoribus gestarum, tibri iv. Commentatio (Heidelberg, 1811); Finlay, History of Greece (vol. iii., Oxford, 1877); Gibbon, Decline and Fall of the Roman Empire, edited with notes, &c., by Prof. J. B. Bury (London, 1898), where further authorities are cited; F. Chalandon, Essai sur le regne d'Alexis Ier, Comnene (1900). (J. B. B.)

ALEXIUS II. (COMNENUS) (1167-1183), emperor of the East, was the son of Manuel Comnenus and Maria, daughter of Kaymund, prince of Antioch, and was born at Constantinople on the 10th of September 1167. On Manuel's death, Maria, who hid been immured in a convent under the name of Xene, had herself proclaimed regent (1179-1180), and handing over her son to evil counsellors, who encouraged him in every vice, supported the government of Alexius the protosebastos (nephew of Manuel), who was supposed to be her lover. The young Alexius and his friends now tried to form a party against the empress mother and the protosebastos; and his sister Maria, wife of Caesar John, stirred up riots in the streets of the capital. Their party was defeated (May 2, 1182), but Andronicus Comnenus took advantage of these disorders to aim at the crown, entered Constantinople, where he was received with almost divine honours, and overthrew the regents. His arrival was celebrated by a barbarous massacre of the Latins in Constantinople, which he made no attempt to stop. He allowed Alexius to be crowned, but forced him to consent to the death of all his friends, including his mother, his sister and the Caesar, and refused to allow him the smallest voice in public affairs. The betrothal in 1180 of Alexius with Agnes, daughter of Louis VII. of France, a child of nine, was quashed, and he was married to Irene, daughter of Andronicus. The latter was now formally proclaimed as co-emperor, and not long afterwards, on the pretext that divided rule was injurious to the Empire, he caused Alexius to be strangled with a bow-string (October 1183). (J. B. B.)

ALEXIUS III. (ANGELUS), emperor of the East, was the second son of Andronicus Angelus, nephew of Alexius I. In 1195, while his brother Isaac II. was away hunting in Thrace, he was proclaimed emperor by the troops; he captured Isaac at Stagira in Macedonia, put out his eyes, and kept him henceforth a close prisoner, though he had been redeemed by him from captivity at Antioch and loaded with honours. To compensate for this crime and to confirm his position as emperor, he had to scatter money so lavishly as to empty his treasury, and to allow such licence to the officers of the army as to leave the Empire practically defenceless. He consummated the financial ruin of the state. The empress Euphrosyne tried in vain to sustain his credit and his court; Vatatzes, the favourite instrument of her attempts at reform, was assassinated by the emperor's orders. Eastward the Empire was overrun by the Turks; from the north Bulgarians and Vlachs descended unchecked to ravage the plains of Macedonia and Thrace; while Alexius squandered the public treasure on his palaces and gardens. Soon he was threatened by a new and yet more formidable danger. In 1202 the Western princes assembled at Venice, bent on a new crusade. To them Alexius, son of the deposed Isaac, made appeal, promising as a crowning bribe to heal the schism of East and West if they would help him to depose his uncle. The crusaders, whose objective had been Egypt, were persuaded to set their course for Constantinople, before which they appeared in June 1203, proclaiming the emperor Alexius IV. and summoning the capital to depose his uncle. Alexius III., sunk in debauchery, took no efficient measures to resist. His son-in-law, Lascaris, who was the only one to do anything, was defeated at Scutari, and the siege of Constantinople began. On the 17th of July the crusaders, the aged doge Dandolo at their head, scaled the walls and took the city by storm. During the fighting and carnage that followed Alexius hid in the palace, and finally, with one of his daughters, Irene, and such treasures as he could collect, got into a boat and escaped to Develton in Thrace, leaving his wife, his other daughters and his Empire to the victors. Isaac, drawn from his prison and robed once more in the imperial purple, received hs son in state.

Shortly afterwards Alexius made an effort in conjunction with Murtzuphlos (Alexius V.) to recover the throne. The attempt was unsuccessful and, after wandering about Greece, he surrendered with Euphrosyne, who had meanwhile joined him, to Boniface of Montferrat, then master of a great part of the Balkan peninsula. Leaving his protection he sought shelter with Michael, despot of Epirus, and then repaired to Asia Minor,where his son-in-law Lascaris was holding his own against the Latins. Alexius, joined by the sultan of Iconium (Konieh), now demanded the crown of Lascaris, and on his refusal marched against him. Lascaris, however, defeated and took him prisoner. Alexius was relegated to a monastery at Nicaea, where he died on some date unknown.

AUTHORITIES.--Nicetas Acominatus, George Acropolites, Nicephorus Gregoras; and the sources for the Fourth Crusade (see CRUSADES). (J. B. B.)

ALEXIUS V., eastern Roman emperor, was proclaimed emperor on the 5th of February 1204, during the siege of Constantinople by the Latins (Fourth Crusade). His name was Alexius Ducas Murtzuphlos, and he was a connexion of the imperial house of the Angell. His elevation was the result of a revolution in the city against Isaac II. and Alexius IV. He conducted the defence with great bravery till it became hopeless (April 12), whereupon he fled. He would then have made common cause with Alexius III. against the Latins, but was blinded by that ex-monarch and fell into the hands of the crusaders, who put him to death by casting him from the top of the Pillar of Theodosius as the murderer of Alexius IV.

ALEXIUS MIKHAILOVICH (1624-1676), tsar of Muscovy, the son of Tsar Michael Romanov and Eudoxia Stryeshnevaya, was born on the 9th of March 1629. A youth at his father's death (1645), he was committed to the care of the boyarin Boris Ivanovich Morozov, a shrewd and sensible guardian, sufficiently enlightened to recognize the needs of his country, and by no means inaccessible to Western ideas. Morozov's foreign policy was pacificatory. He secured the truce with Poland and carefully avoided complications with the Porte. His domestic policy was severely equitable, and aimed at relieving the public burdens by limiting the privileges of foreign traders and abolishing a great many useless and expensive court offices. On the 17th of January 1648 he procured the marriage of the tsar with Maria Miloslavshaya, himself marrying her sister, Anna, ten days later. The Miloslavskis were typical self-seeking 17th century boyars, whose extortions made them generally detested. In May 1648 the people of Moscow rose against them, and the young tsar was compelled to dismiss both them and their patron Morozov. The successful issue of the Moscow riots was the occasion of disquieting disturbances all over the tsardom culminating in dangerous rebellions at Pskov and Great Novgorod, with which the government was so unable to cope that they surrendered, practically granting the malcontents their own terms. One man only had displayed equal tact and courage at Great Novgorod, the metropolitan Nikon (q.v.), who in consequence became in 1651 the tsar's chief minister. In 1653 the weakness and disorder of Poland, which had just emerged, bleeding at every pore, from the savage Cossack war, encouraged Alexius to attempt to recover from her secular rival the old Russian lands. On the 1st of October 1653 a national assembly met at Moscow to sanction the war and find the means of carrying it on, and in April 1654 the army was blessed by Nikon (now patriarch). The campaign of 1654 was an uninterrupted triumph, and scores of towns, including the important fortress of Smolensk, fell into the hands of the Muscovites. In January 1655 the rout of Ochmatov arrested their progress; but in the summer of the same year, the sudden invasion by Charles X. of Sweden for the moment swept the Polish state out of existence; the Muscovites, unopposed, quickly appropriated nearly everything which was not already occupied by the Swedes, and when at last the Poles offered to negotiate, the whole grand-duchy of Lithuania was the least of the demands of Alexius. Fortunately for Poland, the tsar and the king of Sweden now quarrelled over the apportionment of the spoil, and at the end of May 1656 Alexius, stimulated by the emperor and the other enemies of Sweden, declared war against her. Great things were expected of the Swedish war, but nothing came of it. Dorpat was taken, but countless multitudes were lost in vain before Riga. In the meantime Poland had so far recovered herself as to become a much more dangerous foe than Sweden, and, as it was impossible to wage war with both simultaneously, the tsar resolved to rid himself of the Swedes first. This he did by the peace of Kardis (July 2, 1661), whereby Muscovy retroceded all her conquests. The Polish war dragged on for six years longer and was then concluded by a truce, nominally for thirteen years, which proved the most durable of treaties. By the truce of Andrussowo (February 11, 1667) Vitebsk, Polotsk and Polish Livonia were restored to Poland, but the infinitely more important Smolensk and Kiev remained in the hands of the Muscovite together with the whole eastern bank of the Dnieper. This truce was the achievement of Athanasy Orduin-Nashchokin, the first Russian chancellor and diplomatist in the modern sense, who after the disgrace of Nikon became the tsar's first minister till 1670, when he was superseded by the equally able Artamon Matvyeev, whose beneficent influence prevailed to the end of the reign. It is the crowning merit of the ever amiable and courteous tsar Alexius that he discovered so many great men (like Nikon, Orduin, Matvyeev, the best of Peter's precursors) and suitably employed them. He was not a man of superior strength of character, or he would never have submitted to the dictation of Nikon. But, on the other hand, he was naturally, if timorously, progressive, or he would never have encouraged the great reforming boyarin Matvyeev. His education was necessarily narrow; yet he was learned in his way, wrote verses, and even began a history of his own times. His last years, notwithstanding the terrible rebellion of Stenka Razin, were deservedly tranquil. By his first consort he had thirteen children, of whom two sickly sons and eight healthy daughters survived him. By his second consort, Natalia Naruishkina, he had two children, the tsarevich Peter and the tsarevna Natalia.

See Robert Nisbet Bain, The First Romanovs (London, 1905). (R. N. B.)

ALEXIUS PETROVICH (1600-1718), Russian tsarevich, the sole surviving son of Peter I. and Eudoxia Lopukhina, was horn on the 19th of February 1690. The young tsar married the boyarinya Lopukhina at his mother's command. We know nothing of the bride except that she was beautiful, modest and ``brought up in the fear of the Lord.'' She would, doubtless, have made a model tsaritsa of the pre-Petrine period, but, unfortunately, she was no fit wife for such a vagabond of genius as Peter the Great. From the first her society bored Peter unspeakably, and, after the birth of their second short-lived son Alexander, on the 3rd of October 1691, he practically deserted her. The young Alexius was ignored by his father till he was nine years old. Peter was a rare and unwelcome guest in his own family, and a son who loved his mother could have little affection for a father who had ever been that mother's worst persecutor. From his sixth to his ninth year Alexius was educated by the diffuse and pedantic Vyazemsky, but after the removal of his mother to the Suzdal Prokovsky Monastery he was confided to the care of learned foreigners, who taught him history, geography, mathematics and French. In 1703 Alexius was ordered to follow the army to the field as a private in a bombardier regiment. In 1704 he was present at the capture of Narva. At this period the preceptors of the tsarevich had the highest opinion of his ability; but, unfortunately, it was not the sort of ability that his father could make use of. He was essentially a student, with strong leanings towards archaeology and ecclesiology. A monastic library was the proper place for this gentle emotional dreamer, who clung so fondly to the ancient traditions. To a prince of his temperament the vehement activity of his abnormally energetic father was very offensive. He liked neither the labour itself nor its object. Yet Peter, not unnaturally, wished his heir to dedicate himself to the service of new Russia, and demanded from him unceasing labour in order to maintain the brand-new state at the high level of greatness to which it had been raised. Painful relations between father and son, quite apart from the personal antipathies already existing, were therefore inevitable. It was an additional misfortune for Alexius that his father should have been too busy to attend to him just as he was growing up from boyhood to manhood. He was left in the hands of reactionary boyars and priests, who encouraged him to hate his father and wish for the death of the tsar-antichrist. His confessor, Yakov Ignatiev, whom he promised to obey as ``an angel and apostle of God,'' was his chief counsellor in these days.

In 1708 Peter sent Alexius to Smolensk to collect provender and recruits, and thence to Moscow to fortify it against Charles XII. At the end of 1709 he went to Dresden for twelve months for finishing lessons in French and German, mathematics and fortification, and, his education completed, he was married, greatly against his will, to the princess Charlotte of Brunswick- Wolfenbuttel, whose sister espoused, almost simultaneously, the heir to the Austrian throne, the archduke Charles. The wedding was celebrated at Torgau on the 14th of October 1711, in the house of the queen of Poland, and three weeks later the bridegroom was hurried away by his father to Thorn to superintend the provisioning of the Russian troops in Poland. For the next twelve months Alexius was kept constantly on the move. His wife joined him at Thorn in December, but in April 1712 a peremptory ukaz ordered him off to the army in Pomerania, and in the autumn of the same year he was forced to accompany his father on a tour of inspection through Finland. Evidently Peter was determined to tear his son away from a life of indolent ease. Immediately on his return from Finland Alexius was despatched by his father to Staraya Rusya and Ladoga to see to the building of new ships. This was the last commission entrusted to him. On his return to the capital Peter, in order to see what progress his son had made in mechanics and mathematics, asked him to draw something of a technical nature for his inspection. Alexius, in order to escape such an ordeal, resorted to the abject expedient of disabling his right hand by a pistol-shot. In no other way could the tsarevich have offended his father so deeply. He had behaved like a cowardly recruit who mutilates himself to escape military service. After this, Peter seemed for a time to take no further interest in Alexius. He left him entirely to himself. He employed him no more. He no longer pressed him to attend public functions. Alexius rejoiced at this welcome change, but he had cause rather to fear it. It marked the deepening of a hatred which might have been overcome. Alexius was evidently consoling himself with the reflexion that the future belonged to him. He was well aware that the mass of the Russian nation was on his side. Nearly all the prelates were devoted to him. Equally friendly were the great boyar families. All Alexius had to do was to sit still, keep out of his father's way as much as possible and await the natural course of events. But with Peter the present was everything. He could not afford to leave anything to chance. All his life long he had been working incessantly with a single object --the regeneration of Russia. What if his successor refused to tread in his father's footsteps or, still worse, tried to destroy his father's work? By some such process of reasoning as this must the idea of changing the succession to the throne, by setting aside Alexius, have first occurred to the mind of Peter the Great. Nevertheless he made one last effort to reclaim his son. On the 22nd of October 1715 Alexius' consort, the princess Charlotte, died, after giving birth to a son, the grand-duke Peter, afterwards Peter II. On the day of the funeral Peter addressed to Alexius a stern letter of warning and remonstrance, urging him no longer to resemble the slothful servant in the parable, and threatening to cut him off, as though he were a gangrenous swelling, if he did not acquiesce in his father's plans. But it was now that Alexius showed what a poor creature he really was. He wrote a pitiful reply to his father, offering to renounce the succession in favour of his baby half-brother Peter, who had been born the day after the princess Charlotte's funeral. As if this were not enough, in January 1716 he wrote to his father for permission to become a monk. Still Peter did not despair. On the 26th of August 1716 he wrote to Alexius from abroad urging him, if he desired to remain tsarevich, to join him and the army without delay. Rather than face this ordeal Alexius fled to Vienna and placed himself under the protection of his brother-in-law, the emperor Charles VI., who sent him for safety first to the Tirolean fortress of Ahrenberg, and finally to the castle of San Elmo at Naples. He was accompanied throughout his journey by his mistress, the Finnish girl Afrosina. That the emperor sincerely sympathized with Alexius, and suspected Peter of harbouring murderous designs against his son, is plain from his confidential letter to George I. of England, whom he consulted on this delicate affair. Peter's agitation was extreme. The flight of the tsarevich to a foreign potentate was a reproach and a scandal. He must be recovered and brought back to Russia at all hazards. This difficult task was accomplished by Count Peter Tolstoi, the most subtle and unscrupulous of Peter's servants; but terrorized though he was, Alexius would only consent to return on his father solemnly swearing, ``before God and His judgment seat,'' that if he came back he should not be punished in the least, but cherished as a son and allowed to live quietly on his estates and marry Afrosina. On the 31st of January 1718 the tsarevich reached Moscow. Peter had already determined to institute a most searching inquisition in order to get at the bottom of the mystery of the flight. On the 18th of February a ``confession'' was extorted from Alexius which implicated most of his friends, and he then publicly renounced the succession to the throne in favour of the baby grand-duke Peter Petrovich. A horrible reign of terror ensued, in the course of which the ex-tsaritsa Eudoxia was dragged from her monastery and publicly tried for alleged adultery, while all who had in any way befriended Alexius were impaled, broken on the wheel and otherwise lingeringly done to death. All this was done to terrorize the reactionaries and isolate the tsarevich. In April 1718 fresh confessions were extorted from Alexius, now utterly broken and half idiotic with fright. Yet even now there were no actual facts to go upon. Alexius' ``evil designs'' were still in foro conscientiae, and had not been, perhaps never would be, translated into practice. The worst that could be brought against him was that he had wished his father's death. In the eyes of Peter, his son was now a self-convicted and most dangerous traitor, whose life was forfeit. But there was no getting over the fact that his father had sworn ``before the Almighty and His judgment seat'' to pardon him and let him live in peace if he returned to Russia. From Peter's point of view the question was, did the enormity of the tsarevich's crime absolve the tsar from the oath which he had taken to spare the life of this prodigal son? This question was solemnly submitted to a grand council of prelates, senators, ministers and other dignitaries on the 13th of June 1718. The clergy left the matter to the tsar's own decision. The temporal dignitaries declared the evidence to be insufficient and suggested that Alexius should be examined by torture. Accordingly, on the 19th of June, the weak and ailing tsarevich received twenty-five strokes with the knout (as then administered nobody ever survived thirty), and on the 24th fifteen more. It was hardly possible that he could survive such treatment; the natural inference is that he was not intended to survive it. Anyway, he expired two days later in the guardhouse of the citadel of St Petersburg, two days after the senate had condemned him to death for imagining rebellion against his father, and for hoping for the co-operation of the common people and the armed intervention of his brother-in-law, the emperor. This shameful sentence was the outcome of mingled terror and obsequiousness. Abominable, unnatural as Peter's conduct to his unhappy and innocent son undoubtedly was, there is no reason to suppose that he ever regretted it. He argued that a single worthless life stood in the way of the regeneration of Russia, and he therefore deliberately removed it.

See Robert Nisbet Bain, The First Romanovs (London, 1905). (R. N. B.)

ALFANI, DOMENICO, italian painter, was born at Perugia towards the close of the 15th century. He was a contemporary of Raphael, with whom he studied in the school of Perugino. The two artists lived on terms of intimate friendship, and the influence of the more distinguished of the two is so clearly traceable in the works of the other, that these have frequently been attributed to Raphael. Towards the close of his life Alfani gradually changed his style and approximated to that of the later Florentine school. The date of his death, according to some, was 1540, while others say he was alive in 1553. Pictures by Alfani may be seen in collections at Florence and in several churches in Perugia.

ALFELD, a town of Germany, in the Prussian province of Hanover, 10 m. W. of Hildesheim, on the river Leine and the Hanover-Cassel main line of railway. Pop. (1900) 4900. It has a handsome church with twin spires, and training colleges for schoolmasters and theological candidates. Its industries are flourishing, and embrace paper-making, agricultural machine- works, iron-founding and flax-spinning.

ALFIERI, VITTORIO, COUNT (1749-1803), Italian dramatist, was born on the 17th of January 1749 at Asti in Piedmont. He lost his father in early infancy; but he continued to reside with his mother, who married a second time, till his tenth year, when he was placed at the academy of Turin. After he had passed a twelvemonth at the academy, he went on a short visit to a relation who dwelt at Coni; and during his stay there he made his first poetical attempt in a sonnet chiefly borrowed from lines in Ariosto and Metastasio, the only poets he had at that time read. When thirteen years of age he was induced to begin the study of civil and canonical law; but the attempt only served to disgust him with every species of application and to increase his relish for the perusal of French romances. By the death of his uncle, who had hitherto taken some charge of his education and conduct, he was left, at the age of fourteen, to enjoy without control his vast paternal inheritance, augmented by the recent accession of his uncle's fortune. He now began to attend the riding-school, where he acquired that rage for horses and equestrian exercise which continued to be one of his strongest passions till the close of his existence.

After some time spent in alternate fits of extravagant dissipation and ill-directed study, he was seized with a desire of travelling; and having obtained permission from the king, he departed in 1766, under the care of an English preceptor. Restless and unquiet, he posted with the utmost rapidity through the towns of Italy; and his improvement was such as was to be expected from his mode of travelling and his previous habits. Hoping to find in foreign countries some relief from the tedium and ennui with which he was oppressed, and being anxious to become acquainted with the French theatre, he proceeded to Paris. But he appears to have been completely dissatisfied with everything he witnessed in France and contracted a dislike to its people, which his intercourse in future years rather contributed to augment than diminish. In Holland he became deeply enamoured of a married lady, who returned his attachment, but who was soon obliged to accompany her husband to Switzerland. Alfieri, whose feelings were of the most impetuous description, was in despair at this separation, and returned to his own country in the utmost anguish and despondency of mind. While under this depression of spirits he was induced to seek alleviation from works of literature; and the perusal of Plutarch's Lives, which he read with profound emotion, inspired him with an enthusiastic passion for freedom and independence. Under the influence of this rage for liberty he recommenced his travels; and his only gratification, in the absence of freedom among the continental states, appears to have been derived from contemplating the wild and sterile regions of the north of Sweden, where gloomy forests, lakes and precipices conspired to excite those sublime and melancholy ideas which were congenial to his disposition. Everywhere his soul felt as if confined by the bonds of society; he panted for something more free in government, more elevated in sentiment, more devoted in love and more perfect in friendship. In search of this ideal world he posted through various countries more with the rapidity of a courier than of one who travels for amusement or instruction. During a journey to London he engaged in an intrigue with a married lady of high rank; and having been detected, the publicity of a rencounter with the injured husband, and of a divorce which followed, rendered it expedient and desirable for him to quit England. He then visited Spain and Portugal, where he became acquainted with the Abbe Caluso, who remained through life the most attached and estimable friend he ever possessed. In 1772 Alfieri returned to Turin. This time he became enamoured of the Marchesa Turinetti di Prie, whom he loved with his usual ardour, and who seems to have been as undeserving of a sincere attachment as those he had hitherto adored. In the course of a long attendance on his mistress, during a malady with which she was afflicted, he one day wrote a dialogue or scene of a drama, which he left at her house. On a difference taking place between them the piece was returned to him, and being retouched and extended to five acts, it was performed at Turin in 1775, under the title of Cleopatra.

From this moment Alfieri was seized with an insatiable thirst for theatrical fame, and the remainder of his life was devoted to its attainment. His first two tragedies, Filippo and Polinice were originally written in French prose; and when he came to versify them in Italian, he found that, from his Lombard origin and long intercourse with foreigners, he expressed himself with feebleness and inaccuracy. Accordingly, with the view of improving his Italian style, he went to Tuscany and, during an alternate residence at Florence and Siena, he completed his Filippo and Polinice, and conceived the plan of various other dramas. While thus employed he became acquainted with the countess of Albany, who then resided with her husband at Florence. For her he formed an attachment which, if less violent than his former loves, appears to have been more permanent. With this motive to remain at Florence, he could not endure the chains by which his vast possessions bound him to Piedmont. He therefore resigned his whole property to his sister, the countess Cumiana, reserving an annuity which scarcely amounted to a half of his original revenues. At this period the countess of Albany, urged by the ill-treatment she received from her husband, sought refuge in Rome, where she at length received permission from the pope to live apart from her tormentor. Alfieri followed the countess to that capital, where he completed fourteen tragedies, four of which were now for the first time printed at Sienna.

At length, however, it was thought proper that, by leaving Rome, he should remove the aspersions which had been thrown on the object of his affections. During the year 1783 he therefore travelled through different states of Italy, and published six additional tragedies. The interests of his love and literary glory had not diminished his rage for horses, which seems to have been at least the third passion of his soul. He came to England solely for the purpose of purchasing a number of these animals, which he carried with him to Italy. On his return he learned that the countess of Albany had gone to Colmar in Alsace, where he joined her, and resided with her under the same roof during the rest of his life. They chiefly passed their time between Alsace and Paris, but at length took up their abode entirely in that metropolis. While here, Alfieri made arrangements with Didot for an edition of his tragedies, but was soon after forced to quit Paris by the storms of the Revolution. He recrossed the Alps with the countess, and finally settled at Florence. The last ten years of his life, which he spent in that city, seem to have been the happiest of his existence. During that long period his tranquillity was only interrupted by the entrance of the Revolutionary armies into Florence in 1799. Though an enemy of kings, the aristocratic feeling of Alfieri rendered him also a decided foe to the principles and leaders of the French Revolution; and he rejected with the utmost contempt those advances which were made with a view to bring him over to their cause. The concluding years of his life were laudably employed in the study of the Greek literature and in perfecting a series of comedies. His assiduous labour on this subject, which he pursued with his characteristic impetuosity, exhausted his strength, and brought on a malady for which he would not adopt the prescriptions of his physicians, but obstinately persisted in employing remedies of his own. His disorder rapidly increased, and he died on the 8th of October 1803.

The character of Alfieri may be best appreciated from the portrait which he has drawn of himself in his own Memoirs of his Life. He was evidently of an irritable, impetuous and almost ungovernable temper. Pride, which seems to have been a ruling sentiment, may account for many apparent inconsistencies of his character. But his less amiable qualities were greatly softened by the cultivation of literature. His application to study gradually tranquillized his temper and softened his manners, leaving him at the same time in perfect possession of those good qualities which he had inherited from nature--a warm and disinterested attachment to his family and friends, united to a generosity, vigour and elevation of character, which rendered him not unworthy to embody in his dramas the actions and sentiments of Grecian heroes.

It is to his dramas that Alfieri is chiefly indebted for the high reputation he has attained. Before his time the Italian language, so harmonious in the Sonnets of Petrarch and so energetic in the Commedia of Dante, had been invariably languid and prosaic in dramatic dialogue. The pedantic and inanimate tragedies of the 16th century were followed, during the iron age of Italian literature, by dramas of which extravagance in the sentiments and improbability in the action were the chief characteristics. The prodigious success of the Merope of Maffei, which appeared in the commencement of the 18th century, may be attributed more to a comparison with such productions than to intrinsic merit. In this degradation of tragic taste the appearance of the tragedies of Alfieri was perhaps the most important literary event that had occurred in Italy during the 18th century. On these tragedies it is difficult to pronounce a judgment, as the taste and system of the author underwent considerable change and modification during the intervals which elapsed between the three periods of their publication. An excessive harshness of style, an asperity of sentiment and total want of Poetical ornament are the characteristics of his first four tragedies, Filippo, Polinice, Antigone and Virginia. These faults were in some measure corrected in the six tragedies which he gave to the world some years after, and in those which he published along with Saul, the drama which enjoyed the greatest success of all his productions--a popularity which may be partly attributed to the severe and unadorned manner of Alfieri being well adapted to the patriarchal simplicity of the age in which the scene of the tragedy is placed. But though there be a considerable difference in his dramas, there are certain observations applicable to them all. None of the plots are of his own invention. They are founded either on mythological fable or history; most of them had been previously treated by the Greek dramatists or by Seneca. Rosmunda, the only one which could be supposed of his own contrivance, and which is certainly the least happy effusion of his genius, is partly founded on the eighteenth novel of the third part of Bandello and partly on Prevost's Memoires d'un homme de qualite. But whatever subject he chooses, his dramas are always formed on the Grecian model and breathe a freedom and independence worthy of an Athenian poet. Indeed, his Agide and Bruto may rather be considered oratorical declamations and dialogues on liberty than tragedies. The unities of time and place are not so scrupulously observed in his as in the ancient dramas; but he has rigidly adhered to a unity of action and interest. He occupies his scene with one great action and one ruling passion, and removes from it every accessory event or feeling. In this excessive zeal for the observance of unity he seems to have forgotten that its charm consists in producing a common relation between multiplied feelings, and not in the bare exhibition of one, divested of those various accompaniments which give harmony to the whole. Consistently with that austere and simple manner which he considered the chief excellence of dramatic composition, he excluded from his scene all coups de theatre, all philosophical reflexions, and that highly ornamented Versification which had been so assiduously cultivated by his predecessors. In his anxiety, however, to avoid all superfluous ornament, he has stripped his dramas of the embellishments of imagination; and for the harmony and flow of poetical language he has substituted, even in his best performances, a style which, though correct and pure, is generally harsh, elaborate and abrupt; often strained into unnatural energy or condensed into factitious conciseness. The chief excellence of Alfieri consists in powerful delineation of dramatic character. In his Filippo he has represented, almost with the masterly touches of Tacitus, the sombre character, the dark mysterious counsels, the suspensa semper et obscura verba, of the modern Tiberius. In Polinice, the characters of the rival brothers are beautifully contrasted; in Maria Stuarda, that unfortunate queen is represented unsuspicious, impatient of contradiction and violent in her attachments. In Mirra, the character of Ciniro is perfect as a father and king, and Cecri is a model of a wife and mother. In the representation of that species of mental alienation where the judgment has perished but traces of character still remain, he is peculiarly happy. The insanity of Saul is skilfully managed; and the horrid joy of Orestes in killing Aegisthus rises finely and naturally to madness in finding that, at the same time, he had inadvertently slain his mother.

Whatever may be the merits or defects of Alfieri, he may be considered as the founder of a new school in the Italian drama. His country hailed him as her sole tragic poet; and his successors in the same path of literature have regarded his bold, austere and rapid manner as the genuine model of tragic composition.

Besides his tragedies, Alfieri published during his life many sonnets, five odes on American independence and the poem of Etruria, founded on the assassination of Alexander I., duke of Florence. Of his prose works the most distinguished for animation and eloquence is the Panegyric on Trajan, composed in a transport of indignation at the supposed feebleness of Pliny's eulogium. The two books entitled La Tirannide and the Essays on Literature and Government are remarkable for elegance and vigour of style, but are too evidently imitations of the manner of Machiavel. His Antigallican, which was written at the same time with his Defence of Louis XVI., comprehends an historical and satirical view of the French Revolution. The posthumous works of Alfieri consist of satires, six political comedies and the Memoirs of his Life--a work which will always be read with interest, in spite of the cold and languid gravity with which he delineates the most interesting adventures and the strongest passions of his agitated life.

See Mem. di Vit. Alfieri; Sismondi, De la lit. du midi de l'Europe; Walker's Memoir on Italian Tragedy; Giorn. de Pisa, tom. lviii.; Life of Alfieri, by Centofanti (Florence, 1842); Vita, Giornuli, Lettere di Alfieri, by Teza (Florence, 1861); Vittorio Alfieri, by Antonini and Cognetti (Turin, 1898).

ALFORD, HENRY (1810-1871), English divine and scholar, was born in London on the 7th of October 1810. He came of a Somersetshire family, which had given five consecutive generations of clergymen to the Anglican church. Alford's early years were passed with his widowed father, who was curate of Steeple Ashton in Wiltshire. He was an extremely precocious lad, and before he was ten had written several Latin odes, a history of the Jews and a series of homiletic outlines. After a peripatetic school course he went up to Cambridge in 1827 as a scholar of Trinity. In 1832 he was 34th wrangler and 8th classic, and in 1834 was made fellow of Trinity. He had already taken orders, and in 1835 began his eighteen years' tenure of the vicarage of Wymeswold in Leicestershire, from which seclusion the twice-repeated offer of a colonial bishopric failed to draw him. He was Hulsean lecturer at Cambridge in 1841-1842, and steadily built up a reputation as scholar and preacher, which would have been enhanced but for his discursive ramblings in the fields of minor poetry and magazine editing. In September 1853 Alford removed to Quebec Chapel, London, where he had a large and cultured congregation. In March 1857 Viscount Palmerston advanced him to the deanery of Canterbury, where, till his death on the 12th of January 1871, he lived the same strenuous and diversified life that had always characterized him. The inscription on his tomb, chosen by himself, is ``Diversorium Viatoris Hierosolymam Proficiscentis.''

Alford was a not inconsiderable artist, as his picture-book, The Riviera (1870), shows, and he had abundant musical and mechanical talent. Besides editing the works of John Donne, he published several volumes of his own verse, The School of the Heart (1835), The Abbot of Muchelnaye (1841), and a number of hymns, the best-known of which are ``Forward! be our watch-word,'' ``Come, ye thankful people, come,'' and ``Ten thousand times ten thousand.'' He translated the Odyssey, wrote a well-known manual of idiom, A Plea for the Queen's English (1863), and was the first editor of the Contemporary Review (1866--1870). His chief fame, however, rests upon his monumental edition of the New Testament in Greek (4 vols.), which occupied him from 1841 to 1861. In this work he first brought before English students a careful collation of the readings of the chief MSS. and the researches of the ripest continental scholarship of his day. Philological rather than theological in character, it marked an epochal change from the old homiletic commentary, and though more recent research, patristic and papyral, has largely changed the method of New Testament exegesis, Alford's work is still a quarry where the student can dig with a good deal of profit.

His Life, written by his widow, appeared in 1873 (Rivington). (A. J. G.)

ALFRED, or AELFRED, known as THE GREAT (848-? 900), king of England, was born in 848 at Wantage, and was the fourth son of King AEthelwulf and his first wife (Osburh). He seems to have been a child of singular attractiveness and promise, and stories of his boyhood were remembered. At the age of five (853) he was sent to Rome, where he was confirmed by Leo IV., who is also stated to have ``hallowed him as king.'' Later writers interpreted this as an anticipatory crowning in preparation for his ultimate succession to the throne of Wessex. That, however, could not have been foreseen in 853, as Alfred had three elder brothers living. It is probably to be understood either of investiture with the consular insignia, or possibly with some titular royalty such as that of the under-kingdom of Kent. In 855 Alfred again went to Rome with his father AEthelwulf, returning towards the end of 856. About two years later his father died. During the short reigns of his two eldest brothers, AEthelbald and AEthelberht, nothing is heard of Alfred. But with the accession of the third brother AEthelred (866) the public life of Alfred begins, and he enters on his great work of delivering England from the Danes. It is in this reign that Asser applies to Alfred the unique title of secundarius, which seems to indicate a position analogous to that of the Celtic tanist, a recognized successor, closely associated with the reigning prince. It is probable that this arrangement was definitely sanctioned by the witenagemot, to guard against the danger of a disputed succession should AEthelred fall in battle. In 868 Alfred married Ealhswith, daughter of AEthelred Mucill, who is called ealdorman of the Gaini, an unidentified district. The same year the two brothers made an unsuccessful attempt to relieve Mercia from the pressure of the Danes. For nearly two years Wessex had a respite. But at the end of 870 the storm burst; and the year which followed has been rightly called ``Alfred's year of battles.'' Nine general engagements were fought with varying fortunes, though the place and date of two of them have not been recorded. A successful skirmish at Englefield, Berks (December 31, 870), was followed by a severe defeat at Reading (January 4, 871), and this, four days later, by the brilliant victory of Ashdown, near Compton Beauchamp in Shrivenham Hundred. On the 22nd of January the English were again defeated at Basing, and on the 22nd of March at Marton, Wilts, the two unidentified battles having perhaps occurred in the interval. In April AEthelred died, and Alfred succeeded to the whole burden of the contest. While he was busied with his brother's exequies, the Danes defeated the English in his absence at an unnamed spot, and once more in his presence at Wilton in May. After this peace was made, and for the next five years the Danes were occupied in other parts of England, Alfred merely keeping a force of observation on the frontier. But in 876 part of the Danes managed to slip past him and occupied Wareham; whence, early in 877, under cover of treacherous negotiations, they made a dash westwards and seized Exeter. Here Alfred blockaded them, and a relieving fleet having been scattered by a storm, the Danes had to submit and withdrew to Mercia. But in January 878 they made a sudden swoop on Chippenham, a royal vill in which Alfred had been keeping his Christmas, ``and most of the people they reduced, except the King Alfred, and he with a little band made his way . . . by wood and swamp, and after Easter he . . . made a fort at Athelney, and from that fort kept fighting against the foe'' (Chron..) The idea that Alfred, during his retreat at Athelney, was a helpless fugitive rests upon the foolish legend of the cakes. In reality he was organizing victory. By the middle of May his preparations were complete and he moved out of Athelney, being joined on the way by the levies of Somerset, Wilts and Hants. The Danes on their side moved out of Chippenham, and the two armies met at Edington in Wiltshire. The result was a decisive victory for Alfred. The Danes submitted. Guthrum, the Danish king, and twenty-nine of his chief men accepted baptism. By the next year (879) not only Wessex, but Mercia, west of Watling Street, was cleared of the invader. This is the arrangement known as the peace of Wedmore (878), though no document embodying its provisions is in existence. And though for the present the north-eastern half of England, including London, remained in the hands of the Danes, in reality the tide had turned, and western Europe was saved from the danger of becoming a heathen Scandinavian power. For the next few years there was peace, the Danes being kept busy on the continent. A landing in Kent in 884 or 885,1 though successfully repelled, encouraged the East Anglian Danes to revolt. The measures taken by Alfred to repress this revolt culminated in the capture of London in 885 or 886, and the treaty known as Alfred and Guthrum's peace, whereby the boundaries of the treaty of Wedmore (with which this is often confused) were materially modified in Alfred's favour. Once more for a time there was a lull; but in the autumn of 892 (893) the final storm burst. The Danes, finding their position on the continent becoming more and more precarious, crossed to England in two divisions, amounting in the aggregate to 330 sail, and entrenched themselves, the larger body at Appledore and the lesser under Haesten at Milton in Kent. The fact that the new invaders brought their wives and children with them shows that this was no mere raid, but a deliberate attempt, in concert with the Northumbrian and East Anglian Danes, to conquer England. Alfred, 893 (894), took up a position whence he could observe both forces. While he was negotiating with Haesten the Danes at Appledore broke out and struck north-westwards, but were overtaken by Alfred's eldest son, Edward, and defeated in a general engagement at Farnham, and driven to take refuge in Thorney Island in the Hertfordshire Colne, where they were blockaded and ultimately compelled to submit. They then fell back on Essex, and after suffering another defeat at Benfleet coalesced with Haesten's force at Shoebury. Alfred had been on his way to relieve his son at Thorney when he heard that the Northumbrian and East Anglian Danes were besieging Exeter and an unnamed fort on the coast of North Devon. Alfred at once hurried westwards and raised the siege of Exeter; the fate of the other place is not recorded. Meanwhile the force under Haesten set out to march up the Thames valley, possibly with the idea of assisting their friends in the west. But they were met by a large force under the three great ealdormen of Mercia, Wilts and Somerset, and forced to head off to the north-west, being finally overtaken and blockaded at Buttington, which some identify with Buttington Tump at the mouth of the Wye, others with Buttington near Welshpool. An attempt to break through the English lines was defeated with loss; those who escaped retreated to Shoebury. Then after collecting reinforcements they made a sudden dash across England and occupied the ruined Roman walls of Chester. The English did not attempt a winter blockade, but contented themselves with destroying all the supplies in the neighbourhood. And early in 894 (895) want of food obliged the Danes to retire once more to Essex. At the end of this year and early in 895 (896) the Danes drew their ships up the Thames and Lea and fortified themselves twenty miles above London. A direct attack on the Danish lines failed, but later in the year Alfred saw a means of obstructing the river so as to prevent the egress of the Danish ships. The Danes realized that they were out-manoeuvred. They struck off north-westwards and wintered at Bridgenorth. The next year, 896 (897), they abandoned the struggle. Some retired to Northumbria, some to East Anglia; those who had no connexions in England withdrew to the continent. The long campaign was over. The result testifies to the confidence inspired by Alfred's character and generalship, and to the efficacy of the military reforms initiated by him. These were (1) the division of the fyrd or national militia into two parts, relieving each other at fixed intervals, so as to ensure continuity in military operations; (2) the establishment of fortified posts (burgs) and garrisons at certain points; (3) the enforcement of the obligations of thanehood on all owners of five hides of land, thus giving the king a nucleus of highly equipped troops. After the final dispersal of the Danish invaders Alfred turned his attention to the increase of the navy, and ships were built according to the king's own designs, partly to repress the ravages of the Northumbrian and East Anglian Danes on the coasts of Wessex, partly to prevent the landing of fresh hordes. This is not, as often asserted, the beginning of the English navy. There had been earlier naval operations under Alfred. One naval engagement was certainly fought under AEthelwulf (851), and earlier ones, possibly in 833 and 840. Nor were the new ships a great success, as we hear of them grounding in action and foundering in a storm. Much, too, was needed in the way of civil re-organization, especially in the districts ravaged by the Danes. In the parts of Mercia acquired by Alfred, the shire system seems now to have been introduced for the first time. This is the one grain of truth in the legend that Alfred was the inventor of shires, hundreds and tithings. The finances also would need careful attention; but the subject is obscure, and we cannot accept Asser's description of Alfred's appropriation of his revenue as more than an ideal sketch. Alfred's care for the administration of justice is testified both by history and legend; and the title ``protector of the poor'' was his by unquestioned right. Of the action of the witenagemot we do not hear very much under Alfred. That he was anxious to respect its rights is conclusively proved, but both the circumstances of the time and the character of the king would tend to throw more power into his hands. The legislation of Alfred probably belongs to the later part of the reign, after the pressure of the Danes had relaxed. The details of it cannot be discussed here. Asser speaks grandiosely of Alfred's relations with foreign powers, but little definite information is available. He certainly corresponded with Elias III., the patriarch of Jerusalem, and probably sent a mission to India. Embassies to Rome conveying the English alms to the pope were fairly frequent; while Alfred's interest in foreign countries is shown by the insertions which he made in his translation of Orosius. His relations to the Celtic princes in the southern half of the island are clearer. Comparatively early in his reign the South Welsh princes, owing to the pressure on them of North Wales and Mercia, commended themselves to Alfred. Later in the reign the North Welsh followed their example, and the latter co-operated with the English in the campaign of 893 (894). The Celtic principality in Cornwall, which seems to have survived at least till 926, must long have been practically dependent on Wessex. That Alfred sent alms to Irish as well as to continental monasteries may be accepted on Asser's authority; the visit of the three pilgrim ``Scots'' (i.e. Irish) to Alfred in 891 is undoubtedly authentic; the story that he himself in his childhood was sent to Ireland to be healed by St Modwenna, though mythical, may point to Alfred's interest in that island. The history of the church under Alfred is most obscure. The Danish inroads had told heavily upon it; the monasteries had been special points of attack, and though Alfred founded two or three monasteries and imported foreign monks, there was no general revival of monasticism under him. To the ruin of learning and education wrought by the Danes, and the practical extinction of the knowledge of Latin even among the clergy, the preface to Alfred's translation of Gregory's Pastoral Care bears eloquent testimony. It was to remedy these evils that he established a court school, after the example of Charles the Great; for this he imported scholars like Grimbald and John the Saxon from the continent and Asser from South Wales; for this, above all, he put himself to school, and made the series of translations for the instruction of his clergy and people, most of which still survive. These belong unquestionably to the later part of his reign, not improbably to the last four years of it, during which the chronicles are almost silent. Apart from the lost Handboc or Encheiridion, which seems to have been merely a commonplace-book kept by the king, the earliest work to be translated was the Dialogues of Gregory, a book enormously popular in the middle ages. In this case the translation was made by Alfred's great friend Werferth, bishop of Worcester, the king merely furnishing a preface. The next work to be undertaken was Gregory's Pastoral Care, especially for the benefit of the clergy. In this Alfred keeps very close to his original; but the introduction which he prefixed to it is one of the most interesting documents of the reign, or indeed of English history. The next two works taken in hand were historical, the Universal History of Orosius and Bede's Ecclesiastical History of the English People. The priority should probably be assigned to the Orosius, but the point has been much debated. In the Orosius, by omissions and additions, Alfred so remodels his original as to produce an almost new work; in the Bede the author's text is closely adhered to, no additions being made, though most of the documents and some other less interesting matters are omitted. Of late years doubts have been raised as to Alfred's authorship of the Bede translation. But the sceptics cannot be regarded as having proved their point. We come now to what is in many ways the most interesting of Alfred's works, his translation of Boethius' Consolation of Philosophy, the most popular philosophical manual of the middle ages. Here again Alfred deals very freely with his original and though the late Dr G. Schepss showed that many of the additions to the text are to be traced not to Alfred himself, but to the glosses and commentaries which he used, still there is much in the work which is solely Alfred's and highly characteristic of his genius. It is in the Boethius that the oft-quoted sentence occurs: ``My will was to live worthily as long as I lived, and after my life to leave to them that should come after, my memory in good works.'' The book has come down to us in two MSS. only. In one of these the poems with which the original is interspersed are rendered into prose, in the other into alliterating verse. The authorship of the latter has been much disputed; but probably they also are by Alfred. Of the authenticity of the work as a whole there has never been any doubt. The last of Alfred's works is one to which he gave the title Blostman, i. e. ``Blooms'' or Anthology. The first half is based mainly on the Soliloquies of St Augustine, the remainder is drawn from various sources, and contains much that is Alfred's own and highly characteristic of him. The last words of it may be quoted; they form a fitting epitaph for the noblest of English kings. ``Therefore he seems to me a very foolish man, and very wretched, who will not increase his understanding while he is in the world, and ever wish and long to reach that endless life where all shall be made clear.'' Besides these works of Alfred's, the Saxon Chronicle almost certainly, and a Saxon Martyrology, of which fragments only exist, probably owe their inspiration to him. A prose version of the first fifty Psalms has been attributed to him; and the attribution, though not proved, is perfectly possible. How Alfred passed to ``the life where all things are made clear'' we do not know. The very year is uncertain. The arguments on the whole are in favour of 900. The day was the 26th of October. Alike for what he did and for what he was, there is none to equal Alfred in the whole line of English sovereigns; and no monarch in history ever deserved more truly the epithet of Great.

BIBLIOGRAPHY.--The chief original authorities for the reign of Alfred are the so-called Life by Asser (best edition by W. H. Stevenson, Clarendon Press, 1904); and the Saxon Chronicles (text and notes by Earle and Plummer, 2 vols., Clar. Press, 1892-1899; parallel texts and translation, Thorpe, 2 vols., 1861, Rolls Series; translation alone, Joseph Stevenson in Church Historians of England, vol. ii., 1853). The above sketch is based mainly on C. Plummer's Life and Times of Alfred the Great (Clar. Press, 1902). Of earlier biographies that by Pauli is still of great value: Konig AElfred (Berlin, 1851); Eng. trans. by Thorpe (Bohn, 1853). Of recent works mention may be made of Alfred the Great, Chapters on his Life and Times, by various authors, edited by Alfred Bowker (1899); Earle, The Alfred Jewel (Clar. Press, 1901).

For the bioliography of Alfred's works in general see Wulker, Grundriss zur Gesch. der angelsachsischen Litteratur, pp. 386-451 (Leipzig, 1885). Only the more recent and accessible editions are mentioned here. Laws: The Legal Code ofAElfred the Great (M. H. Turk, Halle, 1893). (For the Anglo-Saxon laws as a whole see Liebermann, Gesetze der Angelsachsen, Halle, 1898-1903. Earlier editions, Schmid, 1858; Thorpe, 1840.) Gregory's Dialogues: Hans Hecht, in Grein's Bibliothek der angels. Prosa (1900). Gregory's Pastoral Care: H. Sweet, for Early Eng. Text Society (1871--1872). (Dissertations by Wack and DeWitz, 1889.) Orosius: Thorpe (in his translation of Pauli, U. S. 1853); Bosworth (1859); Sweet, E.E.T.S. (1883). (Dissertation Schelling, Konig AElfred's . . . Orosius, Halle, 1886.) Bede: T. Miller, for E.E.T.S. (1890); Prof. Schipper, in Grein's Bibliothek (U.S. 1899). Boethius: W. J. Sedgfield (Clar. Press, 1899); translation by the same (1900). (Dissertation: G. Schepss, Archiv fur's Studium der neueren Sprachen, xciv. 14-160.) Blostman: First printed by Cockayne in the Shrine (1868-1869); reprinted, Englische Studien, xviii.; new edition by Hararove, Yale Studies in English, xiii. (1902); translation by the same, ib. xxii. (1904). (Dissertation: F. G. Hubbard, Modern Language Notes, ix. 522 ff.) Anglo-Saxon Chronicle: see above. Mortyrology: Cockayne, in the Shrine, v.s. Psalter: Thorpe (Clar. Press, 1855). (Dissertations: for Alfred's authorship, Wichmann, Anglia, xi. 19 ff.; against, J. D. Bruce, The Anglo-Saxon Version of the Book of Psalms, Baltimore, 1894.) (C. PL.)

1 Where alternative dates are given the later date is that of the Saxon Chronicle. But the evidence of the Continental Chronicles makes it probable that the Saxon Chronicle is a year in advance of the true chronology in this part.

ALFRED ERNEST ALBERT, duke of Saxe-Coburg and Gotha, and duke of Edinburgh (1844-1900), second son and fourth child of Queen Victoria, was born at Windsor Castle on the 6th of August 1844. In 1856 it was decided that the prince, in accordance with his own wishes, should enter the navy, and a separate establishment was accordingly assigned to him, with Lieutenant Sowell, R. E., as governor. He passed a most creditable examination for midshipman in August 1858, and being appointed to the ``Euryalus,'' at once began to work hard at the practical part of his profession. In July 1860, while on this ship, he paid an official visit to the Cape, and made a very favourable impression both on the colonials and on the native chiefs. On the abdication of Otto, king of Greece, in 1862, Prince Alfred was chosen by the whole people to succeed him, but political conventions of long standing rendered it impossible for the British government to accede to their wishes. The prince therefore remained in the navy, and was promoted lieutenant on the 24th of February 1863 and captain on the 23rd of February 1866, being then appointed to the command of the ``Galatea.'' On attaining his majority in 1865 the prince was created duke of Edinburgh and earl of Ulster, with an annuity of L. 15,000 granted by parliament. While still in command of the ``Galatea'' the duke started from Plymouth on the 24th of January 1867 for his voyage round the world. On the 11th of June 1867 he left Gibraltar and reached the Cape on the 24th of July, and landed at Glenelg, South Australia, on the 31st of October. Being the first English prince to visit Australia, the duke was received with the greatest enthusiasm. During his stay of nearly five months he visited Adelaide, Melbourne, Sydney, Brisbane and Tasmania; and it was on his second visit to Sydney that, while attending a public picnic at Clonfert in aid of the Sailors' Home, an Irishman named O'Farrell shot him in the back with a revolver. The wound was fortunately not dangerous, and within a month the duke was able to resume command of his ship and return home. He reached Spithead on the 26th of June 1868, after an absence of seventeen months. The duke's next voyage was to India, where he arrived in December 1869. Both there and at Hong Kong, which he visited on the way, he was the first British prince to set foot in the country. The native rulers of India vied with one another in the magnificence of their entertainments during the duke's stay of three months. On the 23rd of January 1874 the marriage of the duke to the grand-duchess Marie Alexandrovna, only daughter of Alexander II., emperor of Russia, was celebrated at St Petersburg, and the bride and bridegroom made their public entry into London on the 12th of March. The duke still devoted himself to his profession, showing complete mastery of his duties and unusual skill in naval tactics. He was promoted rear-admiral on the 30th of December 1878; vice-admiral, 10th of November 1882; admiral, 18th of October 1887; and received his baton as admiral of the Fleet, 3rd of June 1893. He commanded the Channel fleet, 1883-1884; the Mediterranean fleet, 1886-1889; and was commander-in-chief at Davenport, 1890- 1893. He always paid the greatest attention to his offiicial duties and was most efficient as an admiral.

On the death of his uncle, Ernest II., duke of Saxe-Coburg and Gotha, on the 22nd of August 1893, the vacant duchy fell to the duke of Edinburgh, for the prince of Wales had renounced his right to the succession. At first regarded with some coldness as a ``foreigner,'' he gradually gained popularity, and by the time of his death, on the 30th of July 1900, he had completely won the good opinion of his subjects. The duke was exceedingly fond of music and an excellent violinist, and took a prominent part in establishing the Royal College of music. He was also a keen collector of glass and ceramic ware, and his collection, valued at half a million of marks, was presented by his widow to the ``Veste Coburg,'' near Coburg. When he became duke of Saxe-Coburg he surrendered his English allowance of L. 15,000 a year, but the L. 10,000 granted in addition by parliament on his marriage he retained in order to keep up Clarence House. The duke had one son, who died unmarried on the 6th of February 1899, and four daughters. The third daughter, Princess Alexandra Louisa Olga Victoria, married the hereditary prince Ernest of Hohenlohe-Langenburg, who became regent of the duchy of Coburg during the minority of the deceased duke's nephew, the young duke of Albany, to whom the succession fell. (G. F. B.)

ALFRED, a village in the township of Alfred, Allegany county, New York, U.S.A., about 75 m. S.W. of Buffalo. Pop. of the township, including the village (1900), 1615; (1910 U. S. census) 1590. Pop. of the village (1900) 756; (1910 U. S. census) 759. The township is served, at Alfred station, by the Erie railway. The village, which is connected by stage with the station, is situated at the junction of two valleys and commands delightful views of mountain scenery. On the west slope of pine Hill is Alfred University (co-educational), which embraces a College (non-sectarian), an academy (non-sectarian) and a theological seminary (Seventh-Day Baptist). Closely associated with it also, and under the management of the university trustees, is the New York State School of Clay-Working and Ceramics (1900), one of the most efficient schools of the kind in the country. In 1908 the legislature of New York appropriated $80,000 for the establishment of a state school of agriculture in connexion with the university. The institution had its beginning in 1836 in a private school. This developed into an academy, which in 1843 was incorporated as Alfred Academy and Teachers' Seminary; in 1857 the university was chartered under its present name. The principal industry of the village is the manufacture of roofing tiles. The township of Alfred lies within the territory purchased by Robert Morris in 1791. He sold it in the same year to a company resident in London, England. Their agent sold most of it to settlers and, it is said, named the township, when it was organized in 1806, in honour of Alfred the Great. The first settlement within its present limits was made in 1807. For several years most of the settlers were Seventh-Day Baptists, and in 1812 they organized a church here. The village of Alfred was chartered in 1887.

J. S. Minard, Allegany County and its People (Alfred, 1896).

ALFRETON, a market town in the mid-parliamentary division of Derbyshire, England, 14 m N. by E. of Derby, on the Midland railway. Pop. of urban district (1901) 17,505. It lies at a considerable elevation above the valley of a small stream tributary to the Derwent. The church of St Martin is Early English and later. The neighbourhood abounds in ironworks, collieries, quarries and potteries, and is thickly populated. To the north-east of Alfreton are South Normanton (pop. 5170), Blackwell (4144) and Tibshelf (3432); to the north Shirland (3929), to the south Ironville and other busy industrial villages. The foundation of Alfreton is traditionally ascribed to King Alfred.

ALFUROS (ALFURES, HORAFORAS), a term of no ethnological value applied by the Malays to all the uncivilized non- Mahommedan peoples in the eastern portion of the Malay Archipelago. Its origin is uncertain, but its meaning is ``wild'' or ``uncivilized.'' The term is not restricted to the aborigines, but is far more frequently used to describe the tribes of Malayan blood.

ALGAE. The Latin word alga seems to have been the equivalent of the English word ``seaweed'' and probably stood for any or all of the species of plants which form the ``wrack'' of a seashore.

Classification.

When the word ``Algae'' came to be employed in botanical classification as the name of a class, an arbitrary limitation had to be set to its signification, and this was not always in keeping with its original meaning. The absence of differentiation into root, stem and leaf which prevails among seaweeds, seems, for example, to have led Linnaeus to employ the term in the Genera Plantarum for a sub-class of Cryptogamia, the members of which presented this character in a greater or less degree. Of the fifteen genera included by Linnaeus among algae, not more than six--viz. Chara, Fucus, Diva and Conferva, and in part Tremella and Byssus--would to-day, in any sense in which the term is employed, be regarded as algae. The excluded genera are distributed among the liverworts, lichens and fungi; but notwithstanding the great advance in knowledge since the time of Linnaeus, the difficulty of deciding what limits to assign to the group to be designated Algae still remains. It arises from the fact that algae, as generally understood, do not constitute a homogeneous group, suggesting a descent from a common stock. Among them there exist, as will be seen hereafter, many well-marked but isolated natural groups, and their inclusion in the larger group is generally felt to be a matter of convenience rather than the expression of a belief in their close inter-relationship. Efforts are therefore continually being made by successive writers to exclude certain outlying sub-groups, and to reserve the term Algae for a central group reconstituted on a more natural basis within narrower limits.

It is perhaps desirable, in an article like this, to treat of algae in the widest possible sense in which the term may be used, an indication being at the same time given of the narrower senses in which it has been proposed to employ it. Interpreted in this way, the place of algae in the vegetable kingdom may be shown by means of a

_ _ _ | Myxomycetes | | Thallophyta | Fungi | Cryptogamia | |_ Algae The Vegetable | | Bryophyta Kingdom | |_ Pteridophyta | _ | | Gymnosperms | Phanerogamia |_ Angiosperms |_

Algae in this wide sense may be briefly described as the aggregate of those simpler forms of plant life usually devoid, like the rest of the Thallophyta, of differentiation into root, stem and leaf; but, unlike other Thallophyta, possessed of a colouring matter; by means of which they are enabled, in the presence of sunlight, to make use of the carbonic acid gas of the atmosphere as a source of carbon. It is true that certain Bryophyta (Marchantiaceae, Anthoceroteae) possess a thalloid structure similar to that of Thallophyta, and are at the same time possessed of the colouring matter of the Green Algae. Their life-cycle, however, the structure of the reproductive organs and their whole organization proclaim them to be Bryophyta (q.v..) On the other hand, certain undoubted animals (Stentor, Hydra, Bonellia) are provided with a green colouring matter by means of which they make use of atmospheric carbonic acid. A more important consideration is the occasional absence of this colour in species, or groups of species, with, in other respects, algal affinities. Such aberrant forms are to be regarded in the same light as Cuscuta and Orobanchaceae, for example, among Phanerogams. As these non-green plants do not cease to be classed with other Phanerogams, so must the forms in question be retained among algae. In all cases the loss of the colouring matter is associated with an incapacity to take up carbon from so simple a compound as carbonic acid

It might be mentioned here that the whole group of the Fungi (q.v.),with its many thousands of species, is now generally regarded as having been derived from algae, and the system of classification of fungi devised by Brefeld is based upon this belief. The similarity of the morphological characters of one group of fungi to those of certain algae has earned for it the name Phycomycetes or alga-fungi.

Further discussion of the general characters of algae will be deferred in order to take a brief survey of the subdivisions of the group. For this purpose there will be adopted the classification of algae into four sub-groups, founded on the nature of the colouring matters present in the plant:-- I. CYANOPHYCEAE, or Blue-green Algae. II. CHLOROPHYCEAE, or Green Algae. III. PHAEOPHYCEAE, or Brown Algae. IV. RHODOPHYCEAE, or Red Algae. The merits and demerits of this system will appear during the description of the characters of the members of the several subdivisions.

I. CYANOPHYCEAE.--This group derives its name from the circumstance that the cells contain in addition to the green colouring matter, chlorophyll, a blue-green colouring matter to which the term phycocyanin has been applied.

Sub-divisions.

To the eye, however, members of this group present a greater variety of colour than those of any other--yellow, brown, olive, red, purple, violet and variations of all these being known. They undoubtedly represent the lowest grade of algal life, and their distribution rivals that of the Green Algae. They occur in the sea, in fresh water, on moist earth, on damp rocks and on the bark of trees. Certain species are regularly found in the intercellular spaces of higher plants; such are species of Nostoc in the thallus of Anthoceros, the leaves of Azolla and the roots of Cycads. Many of them enter into the structure of the lichen-thallus, as the so-called gonidia. It is remarkable that species belonging to the Oscillatoriaceae are known to flourish in hot springs, the temperature of which rises as high as 85 deg. C.

The thallus may be unicellular or multicellular. When unicellular, it may consist of isolated cells, but more commonly the cells are held together in a common jelly (Chroococcaceae) derived from the outer layers of the cell-wall. The multicellular species consist of filaments, branched or unbranched, which arise by the repeated divisions of the cells in parallel planes, no formation of mucilage occurring in the dividing walls. Such filaments may not give rise to mucilage on the lateral surface either, in which case they are said to be free; when mucilage does occur on the lateral wall, it appears as the sheath surrounding either the single filament, or a sheaf of filaments of common origin. The mucilage may also form an embedding substance similar to that of Chroococcaceae, in which the filaments lie parallel or radiate from a common centre (Rivulariaceae). The cells of the filament may be all alike, and growth may occur equally in all parts (Oscillatoriaceae); or certain cells (heterocysts) may become marked off by their larger size and the transparency of their contents; in which case growth may still be distributed equally throughout (Nostoc), or the filament may be attached where the heterocyst arises, and grow out at the opposite extremity into a fine hair (Rivulariaceae). An African form (Camptothrix), devoid of heterocysts and hair-like at both extremities, has recently been described. Branching has been described as ``false'' and ``true.'' The former arises when a filament in a sheath, either in consequence of growth in length beyond the capacity of the sheath to accommodate it,

FIG, 1.--Cyanophyceae, variously magnified.

A. Gloeocapsa sp.,colony in mucilage.

B. Phormidium sp., single filament with hormogonium.

C. Microcoleus sp., several filaments in common sheath.

D. Nostoc sp., young colony-filament with heterocysts.

E. Scytonema sp., false branching.

F. Rivularia sp.

G. Stigonema sp., with hormogonium and true branching.

H. Spirulina sp.

(From Engler and Prantl, Pflanzenfamilien, by permission of Wilhelm Engelmann.)

or because of the decay of a cell, becomes interrupted by breaking, and the free ends slip past one another. ``True'' branching arises only by the longitudinal division of a cell of a filament and the lateral outgrowth of one of the cells resulting from the division (Sirosiohonaceae).

The nature of the contents of the cells of Cyanophyceae has given rise to considerable controversy. The cells are for the most part exceedingly minute, and are not easy to free from their colouring matters, so that investigation has been attended with great difficulty. Occupying as these algae do perhaps the lowest grade of plant life, it is a matter of interest to ascertain whether a nucleus or chromatophore is differentiated in their cells, or whether the functions and properties of these bodies are diffused through the whole protoplast. It is certain that the centre of the cell, which is usually non-vacuolated, is occupied by protoplasm of different properties from the peripheral region; and A. Fischer has further established the fact that the peripheral mass, which is a hollow sphere in spherical cells, and either a hollow cylinder or barrel-shaped body in filamentous forms, must be regarded as the single chromatophore of the Cyanophyceous cell. But what precisely is the nature of the central mass is still uncertain. Some investigators, such as R. Hegler, F. G. Kohl and E. W. Olive, claim that this body is a true nucleus comparable with that of the higher plants. It is said to undergo division by a mitosis essentially of the same character, with the formation of a spindle and the differentiation of chromosomes. It is further stated by Olive that the chromosomes undergo longitudinal fission, and that for the same species the same number of chromosomes appear at each division. H. Wager speaks with greater reserve, acknowledging, however, the central body to be a nucleus of a rudimentary type, but devoid of nuclear membrane and nucleolus. He thinks it may possibly originate in the vacuolization of the central region, and the accumulation of chromatin granules therein. He finds no spindle fibres or true chromosomes, and considers the division direct, not indirect. With reference to the existence of a chromatophore, he with others finds the colouring matter localized in granules in the peripheral region, but does not consider these individually or in the aggregate as chromatophores. Among other contents of the cell, fatty substances and tannin are known. A curious adaptation seems to occur in certain floating forms, in the presence of a gas-vacuole, which may be made to vary its volume with varying pressure. There is evidence that the dividing wall of filamentous forms is deeply pitted, as is found to be the case in red algae. Reproduction is chiefly effected by the vegetative method. Asexual reproductive cells are not infrequent, but sexual reproduction even in its initial stages is unknown. Nor is motility by means of cilia known in the group. In the unicellular forms, cell-division involves multiplication of the plant. In all the multicellular plants of this group which have been adequately investigated, vegetative multiplication by means of what are known as hormogonia has been found to occur. These are short segments of filaments consisting of a few cells which disengage themselves from the ambient jelly, if it be present, in virtue of a peculiar creeping movement which they possess at this stage. After a time they come to rest and give rise to new colonies. True reproduction of the asexual kind occurs, however, in the formation of sporangia, particularly in the Chamaesiohonaceae. Here the contents of certain cells break up endogenously into a great number of spores, which are distributed as a fine dust. Resting spores are also known. In these cases, certain cells of a colony of unicellular plants or of the filaments of multicellular plants enlarge greatly and thicken their wall. When unfavourable external conditions supervene and the ordinary cells become atrophied, these cells persist and reproduce the plant with the return of more favourable conditions. The Oscillatoriaceae are capable of a peculiar oscillatory movement, which has earned for them their name, and which enables them to move through considerable distances. It is not clear how the movement is effected, though it has frequently been the subject of careful investigation.

With the Cyanophyceae must be included, as their nearest allies, the Bacteriaceae (see BACTERIOLOGY.) Notwithstanding the absence of chlorophyll, and the consequent parasitic or saprophytic habit, Bacteriaceae agree in so many morphological features with Cyanophyceae that the affinity can hardly be doubted.

A census of the Cyanophyceae with their two main groups is given below:--

1. Coccogoneae--2 families, 29 genera, 253 species. 2. Hormogoneae--6 families, 59 genera, 701 species. (Engler and Prantl's Pflanzenfamilien, 1900)

II. CHLOROPHYCEAE.--This group includes those algae in which the green colouring matter, chlorophyll, is not accompanied by a second colouring matter, as it is in other groups. It consists of three subdivisions--Conjugatae, Euchlorophyceae and Characeae. Of these the first and last are relatively small and sharply defined families, distinguished from the second family, which forms the bulk of the group, by characters so diverse that their inclusion with them in one larger group can only be justified on the ground of convenience. Chlorophyceae include both marine and freshwater plants.

Euchlorophyceae in their turn have been until recently regarded as made up of the three series of families--Protococcales, Confervales and Siphonales. As the result of recent investigations by two Swedish algologists, Bohlin and Luther, it has been proposed to make a re-classification of a far-reaching nature. Algae are withdrawn from each of the three series enumerated above and consolidated into an entirely new group. In these algae, the colouring matter is said to be yellowish-green, not strictly green, and contained in numerous small discoid chromatophores which are devoid of pyrenoids. The products of assimilation are stored up in the form of a fatty substance and not starch. A certain inequality in the character of the two cilia of the zoospores of some of the members of the group has earned for it the title Heterokontae, from the Greek kontos, a punting-pole. In consonance with this name, its authors propose to re-name the Conjugatae; Akontae and Oedogoniaceae with a chaplet of cilia become Stephanokontae, and the algae remaining over in the three series from which the Heterokontae and Stephanokontae are withdrawn become Isokontae. Conjugatae, Protococcales and Characeae are exclusively freshwater; Confervales and Siphonales are both freshwater and marine, but the latter group attains its greatest development in the sea. Some Chlorophyceae are terrestrial in habit, usually growing on a damp substratum, however. Trentepohlia grows on rocks and can survive considerable desiccation. Phycopeltis grows on the surface of leaves, Phyllobium and Phyllosiphon in their tissues. Gomontia is a shell-boring alga, FIG. 2.--Chlorophyceae, variously magnified.

A. Chlamydomonas sp., unicellular; chr., chromatophore; p., pyrenoid; n., nucleus; p.v., pulsating vacuoles; e.s., eyespot.

B1. Volvox sp., with a, antheridia, and o, oogonia.

B2. Volvox sp., surface view of a single cell showing connexions.

C. Pandorina sp., a 16-celled colony.

D. Hydrodictyon, a single mesh surrounded by 6 cells.

E. Microspora sp., showing H-pieces in the wall.

F. Entoderma sp., endophytic in Ectocarpus.

G. Coleochaete sp., growing as a plate.

H. Oedogonium sp., intercalated growth by insertion of new piece (a) leaving caps.

K. Struvea sp., showing branches forming a net-work.

L. Caulerpa sp., showing portion of axis with leaf-like and root- like appendages.

M1. Chara sp., axis with leaf-like appendages and a branch.

M2. Chara sp., apical region.

N. Botrydium, a simple siphonaceous alga with root-like attachment.

O. Acetabularia Mediterranea, mushroom-like calcareous siphonaceous alga.

(A, C, E, F, G, H, K, M1, M2, from from Engler and Prantl, Pflanzenfamilien, by permission of Wilhelm Engelmann; B1, N, from Vines, Student's Text Book of Botany, by permission of Swan Sonnenschein and Co.; B2, D, O from Oltmanns, Morphologie u. Biologie der Algen, by permission of Gustav Fischer.)

Dermatophyton grows on the carapace of the tortoise and Trichophilus in the hairs of the sloth. Certain Protococcales and Confervales exist as the gonidia of the lichenthallus.

The thallus is of more varied structure in this group than in any other. In the simplest case it may consist of a single cell, which may remain free during the whole of the greater part of its existence, or be loosely aggregated together within a common mucilage, or be held together by the adhesion of the cell-walls at the surface of contact. These aggregations or colonies, as they are termed, may assume the form of a plate, a ring, a solid sphere, a hollow sphere, a perforate sphere, a closed net, or a simple or branched filament. It is not easy in all cases to draw a distinction between a colony of planes and a multicellular individual. in a Volvox sphere, for example, there is a marked protoplasmic continuity between all the cells of the colony. The Ulvaceae, the thallus of which consists of laminae, one or more cells thick, or hollow tubes, probably represent a still more advanced stage in the passaae of a colony into a multicellelar plant. Here there is some amount of localization of growth and distinction of parts. It is only in such cases as Volvox and Ulvaceae that there is any pretension to the formation of a true parenchyma within the limits of the Chlorophyceae. In the whole series of the Confervales, the thallus consists of filaments branched or unbranched, attached at one extremity, and growing almost wholly at the free end. The branches end in fine hairs in Chaetophoraceae. In Coleochaetaceae the branches are often welded into a plate, simulating a parenchyma. In all Conjugatae and most Protococcales, and in the bulk of the Confervales, the thallus consists of a cell or cells, the Protoplast of which contains a single nucleus. In Hydrodictyaceae, Cladophoraceae, Sphaeropleaceae and Gomontiaceae this is no longer the case. Instead of a single relatively large nucleus, each cell is found to contain many small nuclei, and is spoken of as a coenocyte. This character becomes still more pronounced in the large group of the Siphonales. Valoniaceae and Dasycladaceae are partially septate, but elsewhere no cellulose partitions occur, and the thallus is more or less the continuous tube from which the group is named. Yet the siphonaceous algae may assume great variety of form and reach a high degree of differentiation. Protosiphon and Botrydium, on the one hand, are minute vesicles attached to muddy surfaces by rhizoids; Caulerpa, on the other, presents a remarkable instance of the way in which much the same external morphology as that of cormophytes has been reached by a totally different internal structure. Many Siphonales are encrusted with lime like Corallina among Red Algae. Penicillus is brush-like, Hallimeda and Cymopolia are jointed, Acetabularia has much the same external form as an expanded Coprinus, Neomeris simulates the fertile shoot of Equisetum with its densely packed whorled branches, and in Microdictyon, Anadyomene, Struvea and Boodlea the branches, spreading in one plane, become bound together in a more or less close network. Characeae are separated from other Chloroohlceae by a long interval, and present the highest degree of differentiation of parts known among Green Algae. Attached to the bottom of pools by means of rhizoids, the thallus of Characeae grows upwards by means of an apical cell, giving off whorled appendages at regular intervals. The appendages have a limited growth; but in connexion with each whorl there arise, singly or in pairs, branches which have the same unlimited growth as the main axis. There is thus a close approach to the external morphology of the higher plants. The streaming of the protoplasm, known elsewhere among Chlorophyceae, is a conspicuous feature of the cells of Characeae.

The Chlorophyceae excel all other groups of algae in the magnitude and variety of form of the chlorophyll-bodies. In Ulva and Mesocarpus the chromatophore is a single plate, which in the latter genus places its edge towards the incident light; in Spirogyra they are spiral bands embedded in the primordial utricle; in Zygnema they are a pair of stellate masses, the rays of which branch peripherally; in Oedogonium they are longitudinally-disposed anastomosing bands; in Desmids plates with irregular margins; in Cladophora polyhedral plates: in Vaucheria minute elliptical bodies occurring in immense numbers. Embedded in the chromatophore, much in the same way as the nucleus is embedded in the cytoplasm, are the pyrenoids. Unknown in Cyanophyceae and Phoeophyeeae, known only in Bangiaceae and Nemalion among Rhodophyceae, they are of frequent occurrence among Chlorophyceae, excepting Characeae. Sometimes several pyrenoids occur in each chloroplast, as in Mesocarpus and Spirogyra; sometimes only an occasional chloroplast contains pyrenoid at all, as in Cadophora. The pyrenoid seems to be of proteid nature and gelatinous consistency, and to arise as a new formation or by division of pre-existing pyrenoids. When carbon-assimilation is active, starch-granules crowd upon the surface of the pyrenoid and completely obscure it from view.

Special provision for vegetative multiplication is not common among Chlorophyceae. Valonia and Caulerpa among Siphonales detach portions of their thallus, which are capable of independent growth. In Caulerpa no other means of multiplication is as yet known. In Characeae no fewer than four methods of vegetative reproduction have been described, and the facility with which buds and branches are in these cases detached has been adduced as an evidence of affinity with Bryophyta, which, as a class, are distinguished by their ready resort to vegetative reproduction.

With regard to true reproduction, which is characterized by the formation of special cells, the group Euchlorophyceae is characterized by the production of zoospores (Gr. zoon, animal, spora, seed); that is to say, cells capable of motility through the agency of cilia. Such ciliary motion is known in the adult condition of the cells of Volvocaceae, but where this is not the case the reproductive cells are endowed with motility for a brief period. The zoospore is usually a pyriform mass of naked protoplasm, the beaked end of which where the cilia arise is devoid of colouring matter. A reddish-brown body, known as the eyespot, is usually situated near the limits of the hyaline portion, and in the protoolasm contractile vacuoles similar to those of lower animals have been occasionally detected. The movement of the zoospore is effected by the lashing of the cilia and is in the direction of the beak, while the zoospore slowly rotates on Botrydium and Hydrodictyon only one is present; in certain species of Cladophora four; in Dasycladus a chaplet, and in Oedogonium a ring of many cilia. The so-called zoospore of Vaucheria is a coenocyte covered over with paired cilia corresponding in position to nuclei lying below. In all other cases, zoospores are uninucleate bodies. Zoospores arise in cells of ordinary size and form termed zoosporangia. In unicellular forms (Sphaerella) the thallus becomes transformed into a zoosporangium at the reproductive stage. In the zoosporangia of Oedogonium, Tetraspora and Coleochaete the contents become transformed into a single zoospore. In most cases repeated division seems to take place, and the final number is represented by some power of two. In coenocytic forms the zoospores would seem to arise simultaneously, probably because many nuclei are already present. The escape of zoospores is effected by the degeneration of the sporangial wall (Chaetophora), or by a pore (Cladophora), a slit (Pediastrum ), or a circular fracture (Oedogonium). Zoospores are of two kinds: (1) Those which come to rest and germinate to form a new plant; these are asexual and are zoospores proper. (2) Those which are unable to germinate of themselves, but fuse with another cell, the product giving rise to a new individual; these are sexual and are zoogametes (Gr. zoon, animal, and gametes, gamete, husband, wife). When two similar zoogametes fuse, the process is conjugation, and the product a zygospore (Gr. zugon, yoke). Usually, however, only one of the fusing cells is a zoogamete, the other gamete being a much larger resting cell. In such a case the zoogamete is male, is called an antherozoid or spermatozoid, and arises in an antheridium; the larger gamete is an oosphere and arises in an oogonium. The fusion is now known as fertilization, and the product is an oospore. Reproduction by conjugation is also known as isogamy, by fertilization as oogamy. When zoospores come to rest, a new cell is formed and germination ensues at once. When zygospores and oospores are produced a new cell-wall is also formed, but a long period of rest ensues. All investigation goes to show that an essential part of sexual union is the fusion of the two nuclei concerned. It is interesting to know, on the authority of Oltmanns, that when the oosphere is forming in the oogonium of Vaucheria, there is a retrocession of all the included nuclei but one. that the antherozoid of Vaucheria contains a single nucleus had been inferred before.

From a comparison of those Euchlorophyceae which have been most closely investigated, it appears probable that sexual reproductive cells have in the course of evolution arisen as the result of specialization among asexual reproductive cells, and that in turn oogamous reproduction has arisen as the result of differentiation of the two conjugating cells into the smaller male gamete and the larger male gamete. It would further appear that oogamous reproduction has arisen independently in each of the three main groups of Euchlorophyceae, viz. Ptotococcales, Siphonales and Confervales. Thus among Volvocaceae, a family of Protococcales, while in some of the genera (Chloraster, Sphondylomorum) no sexual union has as yet been observed, in others (Pandorina, Chlorogonium, Stephanosphaera, Sphaerella) conjugation of similar gametes takes place, in others still (Phacotus, Eudorina, Volvox) the union is of the nature of fertilization. No other family of Protococcales has advanced beyond the stage of isogamous reproduction. Again, among Siphonales only one family (Vaucheriaceae) has reached the stage of oogamy, although an incipient heterogamy is said to occur in two other families (Codiaceae, Bryopsidaceae). Elsewhere among Siphonales, in those cases where reproductive cells are known, the reproduction is either isogamous or asexual. Among Confervales there is no family in which sexual reproduction--isogamy or oogamy--is not known to occur among some of the component species, and as many as four families (Cylindrocapsaceae, Sphaeropleaceae, Oedogoniaceae, Coleochaetaceae) are oogamous. On these, as well as other grounds. Confervales are regarded as having attained to the highest rank among Euchlorophyceae. Although the phenomena attending isogamous and oogamous reproduction respectively are essentially the same in all cases, slight variations in both instances appear in different families, attributable doubtless to the independent origin of the process in different groups. Thus, although isogamy consists in typical cases of a union of naked motile gametes by a fusion which begins at the beaked ends, and results in the formation of an immotile spherical zygote surrounded by a cell-wall, in Leptosira it is noticeable that the fusion begins at the blunt end; in a species of Chlamydomonas the two gametes are each included in a cell-wall before fusion; and in many cases the zygote retains for some time its motility with the double number of cilia. Again, in oogamous reproduction, while in general only one oosphere is differentiated in the oogonium, in Sphaeroplea several oospheres arise in each oogonium; and while the oospheres usually contract away from the oogonial wall, acquiring for themselves a new cell-wall after fertilization, in Coleochaete the oosphere remains throughout in contact with the oogonial wall. The oosphere is in all cases fertilized while still within the oogonium, the antherozoids being admitted by means of a pore. There is usually distinguishable upon the surface of the oosphere an area free from chlorophyll, known as the receptive spot, at which the fusion with the antherozoid takes place; and in many cases, before fertilization, a small mucilaginous mass has been observed to separate itself off from the oosphere at this point and to escape through the pore. In Coleochaete the oogonial wall is drawn out into a considerable tube, which is provided with an apical pore, and this tube has a somewhat similar appearance to the imperforate trichogyne of Florideae to be hereafter described. In certain species of Oedogonium minute male plantlets, known as dwarf males, become attached to the female plant in the neighbourhood of the oogonia, thus facilitating fertilization. Indeed the genus Oedogonium exhibits a high degree of specialization in its reproductive system, considering that its thallus has not advanced beyond the stage of an unbranched filament.

Many Euchlorophyceae are endowed with both asexual and sexual reproduction. Such are Coleochaete, Oedogonium, Cylindrocapsa, Ulothrix, Vaucheria, Volvox, &c. In others only the asexual method is yet known. When a species resorts to both methods, it is generally found that the asexual method prevails in the early part of the vegetative period and the sexual towards the close of that period. This is in consonance with the facts already mentioned that zoospores germinate forthwith, and that the sexually-produced cell or zygote enters upon a period of rest. It is known that zoogametes, which usually conjugate, may, when conjugation fails, germinate directly (Sphaerella.) In rare cases the oosphere has been known to germinate without fertilization (Oedogonium, Cylindrocapsa.) The germination of a zygospore or oospore is effected by the rupture of an outer cuticularized exosporium; then the cell may protrude an inner wall, the endosporium, and grow out into the new plant ( Vaucheria), or the contents may break up into a first brood of zoospores. It is held that in Coleochaetea parenchyma results from the division of the oospore, from each cell of which a zoospore arises.

Reproduction is also effected among Euchlorophyceae by means of aplanospores and akinetes. Aplanospores would seem to represent zoospores arrested in their development; without reaching the stage of motility, they germinate within the sporangium. Akinetes are ordinary thallus cells, which on account of their acquisition of a thick wall are capable of surviving unfavourable conditions. Both aplanospores and akinetes may germinate with or without the formation of zoospores at the initial stage.

Among Conjugatae reproduction is effected solely by means of conjugation of what are literally aplanospores. Among those Desmidiaceae which live a free life, two plants become surrounded by a common mucilage, in which they lie either parallel (Closterium) or crosswise (Cosmarium.) Gaps then appear in the apposed surfaces, usually at the isthmus; the entire protoplasts either pass out to melt into one another clear of the old walls, or partly pass out and fuse without complete detachment from the old walls. Among colonial Desmidiaceae, the break-up of the filament is a preliminary to this conjugation; otherwise the process is the same. The zygospore becomes surrounded with its own wall, consisting finally of three layers, the outer of which is furnished with spicular prominences of various forms. In Zygnemaceae there is no dissolution of the filaments, but the whole contents of one cell pass over by means of a conjugation-tube into the cavity of a cell of a neighbouring filament, where the zygospore is formed by the fusion of the two

Fig. 3.--Chlorophyceae, variously magnified.

A. Spirogyra sp., in conjugation.

B. Zoospore of Pandorina. B234, stages of conjugation.

C. Ulothrix sp., zoospores escaping. C23, stages of conjugation.

D1. Oedogonium sp., oogonium at moment of fertilization with dwarf male attached.

D2. Oedogonium sp., zoospore with crown of cilia.

E1. Coleochaete sp., with antheridia and an oogonium.

E2. Coleochaete sp., fertilized egg with investment of filaments.

E3. Coleochaete sp., zoospore.

F123. Protosiphon, conjugation of zoogametes.

G. Derbesia sp., zoospore with chaplet of cilia.

H1. Chara sp., oogonium and antheridium at a node on a lateral appendage.

H2. Chara sp., antherozoid.

K1. Vaucheria sp., oogonium and antheridium before fertilization.

K2. Vaucheria sp., after fertilization.

(A from Cooke, British Freshwater Algae, by permission of Kegan Paul, Trench Trubner and Co.; C, E, F. G. H. K from Engler and Prantl, by permission of Wilheim Engelmann; B1 from Vines, by permission of Swan Sonnenschein and Co.; B2, D from Oltmanns, by permission of Gustav Fischer.)

protoplasts. In these cases the activity of one of the gametes, and the passivity of the other, is regarded as evidence of incipient sex. In Strogonium there is cell-division in the parent-cell prior to conjugation; and as two segments are cut off in the case of the active gamete, and only one in the case of the passive gamete, there is a corresponding difference of size, marking another step in the sexual differentiation. In Zygogonium, although no cell-division takes place, the gametes consist of a portion only of the contents of a cell, and this is regularly the case in Mesocarpaceae, which occupy the highest grade among Conjugatae. Some Zygnemaceae and Mesocarpaceae form either a short conjugating tube, or none at all, but the filaments approach each other by a knee-like bend, and the zygospore is formed at the point of contact, often being partially contained within the walls of the parent-cell. It would seem that in some cases the nuclei of the gametes remain distinct in the zygospore for a considerable time after conjugation. It is probable that in all cases nuclear fusion takes place sooner or later. In Zygnemaceae and Mesocarpaceae the zygospore, after a period of rest, germinates, to form a new filamentous colony; in Desmidiaceae its contents divide on germination, and thus give rise to two or more Desmids. Gametes which fail to conjugate sometimes assume the appearance of zygospores and germinate in due course. They are known as azygospores.

The reproduction of Characeae is characterized by a pronounced oogamy, the reproductive organs being the most highly differentiated among Chlorophyceae. The antheridia and oogonia are formed at the nodes of the appendages. The oogonium, seated on a stalk cell, is surrounded by an investment consisting of five spirally-wound cells, from the projecting ends of which segments are cut off, constituting the so-called stigma. The oosphere is not differentiated within the wall of the oogonium, but certain cells known as wendungszellen, the significance of which has given rise to much speculation, are cut off from the basal portion of the parent-cell during its development. The antheridia are spherical orange-coloured bodies of very complex structure. The antherozoid is a spirally-coiled thread of protoplasm, furnished at one end with a pair of cilia. It much more resembles the antherozoids of Bryophyta and certain Pteridophyta than any known among other algae. The fertilized egg charged with food reserves rests for a considerable period, surrounded by its cortex, the whole having assumed a reddish-brown colour. On germination it gives rise to a row of cells in which short (nodal) and long (internodal) cells alternate. From the first node arise rhizoids; from the second a lateral bud, which becomes the new plant. This peculiar product of germination, which intervenes between the oospore and the adult form, is the proembryo. It will be remembered that in Musci, the asexual spore somewhat similarly gives rise to a protonema, from which the adult plant is produced as a lateral bud. The proembryonic branches of Characeae, one of the means of vegetative reproduction already referred to, are so called because they repeat the characters of the proembryo.

Before leaving the Chlorophyceae, it should be mentioned that the genus Volvox has been included by some zoologists (Butschli, for example) among Flagellata; on the other hand, certain green Flagellata, such as Euglena, are included by some botanists (for example, van Tieghem) among unicellular plants. A similar uncertainty exists with reference to certain groups of Phaeophyceae, and the matter will thus arise again.

A census of the Chlorophyceae is furnished below:--

1. Confervoideae---12 families, 77 genera, 1021 species.

2. Siphoneae--9 families, 26 genera, 271 species.

3. Protococcoideae--2 families, 90 genera, 342 species.

4. Conjugateae--2 families, 33 genera, 1296 species. (De Toni's Sylloge Algarum, 1889.)

5. Characeae--2 families, 6 genera, 181 species. (Engler and Prantl's Pflanzenfamilien, 1897)

III. PHAEOPHYCEAE.--The Phaeophyceae are distinguished by the possession of a brown colouring matter, phycophaein, in addition to chlorophyll. They consist of the following groups:--Fucaceae, Phaeosporeae; Dictyotaceae, Cryptomonadaceae, Peridiniaceae and Diatomaceae. Of these the first three include multicellular plants, some of them of great size; the last three are unicellular organisms, with little in common with the rest excepting the possession of a brown colouring matter. Fucaceae and Phaeosporeae are doubtless closely allied, and to these Dictyotaceae may be joined, though the relationship is less close. They constitute the Euphaeophyceae, and will be dealt with in the first place.

Euphaeophyceae are almost exclusively marine, growing on rocks and stones on the coast, or epiphytic upon other algae. In tidal seas they range from the limits of high water to some distance beyond the low-water line. On the British coasts zones are observable in passing from high to low water mark, characterized by the prevalence of different species, thus:---Pelvetia canaliculata, Fucus platycarpus, Fucus vesiculosus, Ascophyllum nodosum, Fucus serratus, Laminaria digitata. Some species are minute filamentous plants, requiring the microscope for their detection; others, like Lessonia, are of considerable bulk, or, like Macrocystis, of enormous length. In Fucaceae, Dictyotacea, and in Laminariaceae and Sphacelariaceae, among Phaeosporeae, the thallus consists of a true parenchyma; elsewhere it consists of free filaments, or filaments so compacted together, as in Cutleriaceae and Desmarestiaceae, as to form a false parenchyma. In Fucaceae and Laminariaceae the inner tissue is differentiated into a conducting system. In Laminariaceae the inflation of the ends of conducting cells gives rise to the so-called trumpet-hyphae. In Nereocystis and Macrocystis a zone of tubes occurs, which present the appearance of sieve-tubes even to the eventual obliteration of the perforations by a callus. While there is a general tendency in the group to mucilaginous degeneration of the cell-wall, in Laminaria digitata there are also glands secreting a plentiful mucilage. Secondary growth in thickness is effected by the tangential division of superficial cells. The most fundamental external differentiation is into holdfast and shoot. In Laminariaceae secondary cylindrical props arise obliquely from the base of the thallus. In epiphytic forms the rhizoids of the epiphyte often penetrate into the tissue of the host, and certain epiphytes are not known to occur excepting in connexion with a certain host; but to what extent, if any, there is a partial parasitism in these cases has not been ascertained. In filamentous forms there is a differentiation into branches of limited and branches of unlimited growth (Sphacelaria.) In Laminariaceae there is a distinction of stipe and blade. The blade is centrally-ribbed in Alaria and laterally-ribbed in Macrocystis. It is among the Sargassaceae that the greatest amount of external differentiation, rivalling that of the higher leafy plants, is reached. A characteristic feature of the more massive species is the occurrence of air-vesicles in their tissues. In Fucus vesiculosus they arise in lateral pairs; in Ascophyllum they are single and median; in Macrocystis one vesicle arises at the base of each thallus segment; in Sargassum and Halidrys the vesicles arise on special branches. They serve to buoy up the plant when attached to the sea-bottom, and thus light is admitted into the forest-like growths of the gregarious species. When such plants are detached they are enabled to float for great distances, and the great Sargasso Sea of the North Atlantic Ocean is probably only renewed by the constant addition of plants detached from the shores of the Caribbean Sea and Gulf of Mexico.

Growth in length is effected in a variety of ways. In Dictyota Sphacelariaceae and Fucaceae there is a definite apical cell. In the first it is a biconvex lens, from which segments are continually cut off parallel to the posterior surface; and in the second an elongated dome, from which segments are cut off by a transverse wall. While, however, in Dictyota the product of the subsequent division in the segment enlarges with each subdivision, the divisions in the cylindrical segment of Sphacelariaceae are such that the whole product after subdivision, however many cells it may consist of, does not exceed in bulk the segment as cut off from the apical cell. In Dictyotaceae the apical cell occasionally divides longitudinally, and thus the dichotomous branching is provided for. In some Sphacelariaceae branches may appear at their inception as lateral protuberances of the apical cell itself. In Fucaceae an apical cell is situate at the surface of the thallus in a slit-like depression at the apex. From this cell segments are cut off in three or four lateral oblique planes.

A peculiar manner of growth in length is that to which the term trichothallic has been applied. It may readily be observed that in the hair-like branches of Ectocarpaceae, the point at which most rapid division occurs is situate near the base of the hair. In Desmarestia and Arthrocladia, for example, it is found that the thallus ends in a tuft of such hairs, each of them growing by means of an intercalated growing point. In these cases, however, the portions of the hairs behind the growing region become agglutinated together into a solid cylindrical pseudo-parenchymatous axis. In Cutleria the laminated thallus is formed in the same way. The intercalated growing region of Laminaria affords an example of another variety of growth in Phaeophyceae. While the laminated portion of the thallus is being gradually worn off in our latitudes during the autumnal storms, a vigorous new growth appears at the junction of the stipe and the blade, as the result of which a new piece is added to the stipe and the lamina entirely renovated.

Both asexual and sexual reproduction occur among Euphaeophyceae. Fucaceae are marked by an entire absence of the asexual method. The sexual organs--oogonia and antheridia---are borne on special portions of the thallus in cavities known as conceptacles. Both organs may occur in one conceptacle, as in Pelvetia, or each may be confined to one conceptacle or even one plant, as in Fucus vesiculosus. The oogonia arise on a stalk cell from the lining layer of the cavity, the contents dividing to form eight oospheres as in Fucus, four as in Ascophyllum, two as in Pelvetia, or one only as in Hallidrys. It would seem that eight nuclei primarily arise in all Fucaceae, and that a number corresponding to the number of oospheres subsequently formed is reserved, the rest being discharged to the periphery, where they may be detected at a late stage. On the maturation of the oospheres the outer layer of the oogonial wall ruptures, and the oospheres, still surrounded by a middle and inner layer, pass out through the mouth of the conceptacle. Then usually these layers successively give way, and the spherical naked oospheres float free in the water. The antheridia, which arise in the conceptacular cavity as special cells of branched filaments, are similarly discharged whole, the antherozoids only escaping when the antheridia are clear of the conceptacle. The antherozoids are attracted to the oospheres, round each of which they swarm in great numbers. Suddenly the attraction ceases, and the oosphere is fertilized, probably at that moment, by the entry of a single antherozoid into the substance of the oosphere; a cell-wall is formed thereupon, in some cases in so short an interval as five minutes. Remarkable changes of size and outline of the oosphere have recently been described as accompanying fertilization in Hallidrys. Probably the act of fertilization in plants has nowhere been observed in such detail as in Fucaceae. Dictyotaceae resemble Fucaceae in their pronounced oogamy. They differ, however, in being also asexually reproduced. The asexual cells are immotile spores arising in fours in sporangia from superficial cells of the thallus. In Dictyota the oospheres arise singly in oogonia, crowded together in sori on the surface of the female plant. The antheridia have a similar origin and grouping on the male plant. Until the recent discovery by Williams of motility, by means of a single cilium, of the antherozoids of Dictyota and Taonia, they were believed to be immotile bodies, like the male cells of red seaweeds. in Dictyota the unfertilized oosphere is found to be capable of undergoing a limited number of divisions, but the body thus formed appears to atrophy sooner or later.

Of the small family of the Tilopteridaceae our knowledge is as yet inadequate, but they probably present the only case of pronounced oogamy among Phaeosporeae. They are filamentous forms, exhibiting, however, a tendency to division in more than one plane, even in the vegetative parts. The discovery by Brebner of the specific identity of Haplospora globosa and Scaphospora speciosa marks an important step in the advance of our knowledge of the group. Three kinds of reproductive organs are known: first, sporangia, which each give rise to a single tetra-, or multi-nucleate non-motile, probably asexual spore; second, plurilocular sporangia, which are probably antheridia, generating antherozoids; and third, sporangia, which are probably oogonia, giving rise to single uni- nucleate non-motile oospheres. No process of fertilization has as yet been observed.

The Cutleriaceae exhibit a heterogamy in which the female sexual cell is not highly specialized, as is in the groups already described. From each locule of a plurilocular sporangium there is set free an oosphere, which, being furnished with a pair of cilia, swarms for a time. In similar organs on separate plants the much smaller antherozoids arise. Fertilization has been observed at Naples; but it apparently depends on climatic conditions, as at Plymouth the oospheres have been observed to germinate parthenogenetically. The asexual organs in the case of Cutleria multifida arise on a crustaceous form, Aglaozonia reptans, formerly considered to be a distinct species. They are unilocular, each producing a small number of zoospores.

The possession of two kinds of reproductive organs, unilocular and plurilocular sporangia, is general among the rest of the Phaeosporeae. Bornet, however, called attention in 1871 to the fact that two kinds of plurilocular sporangia occurred in certain species of the genus Ectocarpus--somewhat transparent organs of an orange tint producing small zoospores, and also more opaque organs of a darker colour producing relatively larger zoospores. On the discovery of another such species by F. H. Buffham, Batters in 1892 separated the three species, Ectocarpus secundus, E. fenestratus, E. Lebelii, together with the new species, into a genus, Giffordia, characterized by the possession of two kinds of plurilocular sporangia. The suspicion that a distinction of sex accompanied this difference of structure has been justified by the discovery by Sauvageau of undoubted fertilization in Gidordia secunda and G. fenestrata. The conjugation of similar gametes, arising from distinct plurilocular sporangia, was observed by Berthold in Ectocarpus siliculosus and Scytosiphon lomentarius in 1880; and these observations have been recently confirmed in the case of the former species by Sauvageau, and in the case of the latter by Kuckuck. In these cases, however, the potential gametes may, failing conjugation, germinate directly, like the zoospores derived from unilocular sporangia. The assertion of Areschoug that conjugation occurs among zoospores derived from unilocular sporangia, in the case of Dictyosiphon hippuroides, is no doubt to be ascribed to error of observation. It would thus seem that the explanation of the existence of two kinds of sporangia, unilocular and plurilocular, among Phaeosporeae, lies in the fact that unilocular sporangia are for asexual reproduction, and that plurilocular sporangia are gametangia--potential or actual. It must, however, be remembered that so important a generalization is as yet supported upon a somewhat narrow base of observation. Moreover, for the important family of the Laminariaceae only unilocular sporangia are known to occur; and for many species of other families, only one or other kind, and in some cases neither kind, has hitherto been observed. The four species--Ectocarpus siliculosus, Giffordia secunda, Cutleria multifida and Haplospora globosa--may be taken to represent, within the phaeosporeae, successive steps in the advance from isogamy to oogamy.

The Peridiniaceae have been included among Flagellata under the title of Dinoflagellata. The majority of the species belong to the sea, but many are found in fresh water. The thallus is somewhat spherical and unicellular, exhibiting a distinction between anterior and posterior extremities, and dorsal and ventral surfaces. The wall consists of a basis of cellulose, and in some cases readily breaks up into a definite number of plates, fitting into one another like the plates of the carapace of a tortoise; it is, moreover, often finely sculptured or coarsely ridged and flanged. Two grooves are a constant feature of the family, one running transversely and anoiher longitudinally. In these grooves lie two c;lia, attached at the point of meeting on the dorsal surface. The protoplast is uninucleate and vacuolate, and contains chromatophores of a brownish colour. It is not clear that FIG. 4.--Phaeophyceae, variously magnified.

A. Halopteris, apical region.

B. Chordaria sp., apical region showing so-called trichothallic growth.

C. Dictyota sp., apical cells immediately after dichotomy.

D. Cutleria sp., margin of thallus showing trichothallic growth.

E. Halidrys, apical depression with leading cell.

F. Macrocystis sp., tubular elements from the medulla, with sieve-like transverse walls.

G. Laminaria sp., hyphae with trumpet-like ends also from medulla.

H. Elachistea sp., Plurilocular sporanges.

K. Ectocarpus sp., unilocular sporange.

L. Ectocarpus siliculosus, female gamete surrounded by male gametes a, b, c, d, e, stages of conjugation.

M. Cutleria multifida. a, antherozoids, b, a female gamete.

N1. Fucus vesiculosus, young oogonium.

N2. Fucus vesiculosus, discharge of eight oospheres from oogonium

O. Laminaria sp., sporanges among paraphyses.

P. Dictyota dichotoma, a sorus of oogonia.

Q. Dictyota dichotoma, part of a sorus of antheridia.

(A, B, C, D, E, H, L, M, P, from Engler and Prantl, by permission of Wilhelm Engelmann; F, G, K, O, from Oltmanns, by permission of Gustav Fischer; Q. from The Annals of Botany, by permission of the Clarendon Press; N1, N2, from Hauck, Meeresalgen, by permission of Eduard Kummer.)

the brown colouring matter which is added to chlorophyll is identical with phycophaein: two varieties of it have been termed phycopyrrin and peridinine. Certain species, such as Gymnodinium spirale, are colourless and therefore saprophytic in their method of nutrition. Multiplication takes place in some cases by the endogenous formation of zoospores, the organism having come to rest; in others by longitudinal division, when the organism is still motile. No method of sexual reproduction is known with certainty.

The Cryptomonadaceae also are unicellular, and live free or in colonies. Each cell contains a flattened chromatophore of a brown or yellow colour. Hydrurus forms a branched gelatinous colony attached to stones in mountain streams. Chromophyton forms an eight-celled colony. Both plants multiply solely by means of zoospores. The Cryptomonadeae and Chromulineae are motile through the greater part of their life. Cryptomonas, when dividing in a mucilage after encystment, recalls the condition in Gloeocystis. In Synura and Chromulina the cells form a spherical motile colony, recalling Volvocaceae. Chromulina is uniciliate, and is contained in a hyaline capsule. Like the Peridiniaceae, the Cryptomonadaceae have been included among Flagellata. They have no close affinity with Euphaeophyceae. Such colonial forms as Hydrurus and Phaeocystis are supposed, however, to indicate a stage in the passage to the multicellular condition.

Diatomaceae have long been recognized as plants. Together with Peridiniaceae they constitute the bulk of marine plankton, and thus play an important part in the support of marine animal life. They exhibit striking adaptations in these circumstances to the floating habit. (See DIATOMACEAE.)

A census of Phaeophyceae is given below:--

(1) Cyclosporinae (Fucaceae)--4 families, 32 genera, 347 species.

(2) Tetrasporinae (Dictyotaceae)-- 1 family, 17 genera, 130 species.

(3) Phaeozoosporineae (Phaeosporeae)--24 families, 143 genera, 571 species. (De Toni's Sylloge ALgarum.)

(4) Peridiniales---3 families, 32 genera, 167 species.

(5) Cryptomonadaceae (including Chrysomonadaceae) --2 families, 28 genera, 50-60 species.

(6) Bacillariales (Diatomaceae)--about 150 genera and 5000 species, fossil and recent.

(Engler and Prantl's Pflanzenfamilien)

IV. RHODOPHYCEAE, or FLORIDEAE.--The members of this group are characterized by the possession of a red colouring matter, phycoerythrin, in addition to chlorophyll. There is, however, a considerable amount of difference in the shades of red which mark different species. The brightest belongs to those species which grow near low-water mark, or under the shade of larger algae at higher levels; species which grow near high-water mark are usually of so dark a hue that they are easily mistaken for brown seaweeds. Rhodophyceae are mostly marine, but not exclusively so. Thorea, Lemanea, Tuomeya, Stenocladia, Batrachospermum, Balbiania are genera belonging entirely to fresh water; and Bangia, Chanitransia, Caloglossa, Bostrychia and Delesseria contain each one or more freshwater species. Most of the larger species of marine Rhodophyceae are attached by means of a disc to rocks, stones or shells. Many are epiphytic on other algae, more especially the larger Phaeophyceae and Rhodophyceae. As in the case of epiphytic brown seaweeds, the rhizoids of the epiphyte often penetrate the substance of the supporting alga. Some Red Algae find a home in the gelatinous substance of Flustra, Alcyonidium and other polyzoa, only emerging for the formation of the reproductive organs. Some are perforating algae and burrow into the substance of molluscan shells, in company with certain Green and Blue-green Algae. Some species belonging to the families Squamariaceae nnd Corallinaceae grow attached through their whole length and breadth, and are often encrusted with lime. The forms which grow away from the substratum vary greatly in external configuration. In point of size the largest cannot rival the larger Brown Algae, while the majority require the aid of the microscope for their investigation.

No unicellular Rhodophyceae are known, although a flagellate organism, Rhodomonas, has recently been described as possessed of the same red colouring matter. If the sub-group, Bangiaceae, be excluded, they may be said to consist exclusively of branched filaments. Growth in these cases takes place by means of an apical cell, from which successive segments are cut off by means of a transverse wall. The segment so cut off does not usually divide again by means of a transverse wall, nor indeed by a longitudinal wall which passes through the organic axis of the cell. New cells may be cut off laterally, which become the apical cells of branches. When the new cells grow no further, but constitute a palisading round the central cell covering its whole length, the condition is reached which characterizes the species of Polysiphonia, the "siphons" of which may be regarded as one-celled branches. To the law that no subsequent transverse division takes place in segments cut off from the apical cell, there seem to be two exceptions: first, the calcareous genus Corallinia, in the pliable joints of which intercalated division occurs; and, second, the Nitophylleae, in which, moreover, median longitudinal division of axial cells is said to occur. Like the Fungi, therefore, the Red Algae consist for the most part of branched filaments, even where the thallus appears massive to the eye, and, as in the case of Fungi, this fact is not inconsistent with a great variery of external morphology. In the great majority the thallus is obviously filamentous, as in some species of Cillithamnion. In other species of that genus an apparent cortication arises by the downward growth of rhizoids, which are retained within the gelatinous wall of the axial cells. in Batrachospermum the whole system of branches are retained within a diffluent gelatinous substance derived from the outer layers of the cell-walls. In other cases the mucilage is denser and the branches more closely compacted Helminthora.) In such cases as Lemanea, the terminal cells of the lateral branches form a superficial layer which has all the appearance of a parenchyma when viewed from the surface. In Champia and allied genera, the cylindrical axis is due not to the derivatives of one axial filament, but of several, the growth of which is co-ordinated to form a septated tube. The branching of the thallus, which meets the eye in all these cases, is due to the unlimited growth of a few branches. When such a lateral branch overtops the main axis whose growth has become limited, as in Plocamium and Dasya, a sympodium is formed. For the most part the branching is monopodial. Besides the differentiation into holdfast and shoot, and into branches of limited and branches of unlimited growth, there appear superficial structures of the nature of hairs. These are for the most part long, thin-walled, unicellular and colourless, and arise from the outer cells of the pseudo-cortex, or from the terminal cells of branches when the filaments are free. Among Rhodomelaceae, hair-like structures of a higher order are known. These arise from the axial cell, and are multicellular and branched. They soon fall off, and it is from the persistent basal cell that the branches of unlimited growth arise. Upon them also the reproductive organs arise in this family. It is not surprising, therefore, that they have been regarded as the rudiments of leaves. In Iridaea the thallus is an entire lamina; in Callophyllis a lobed lamina; in Delesseria it is provided with midrib and veins, simulating the appearance of a leaf of the higher plants; in Constantinea the axis remains cylindrical, and the lateral branches assume the form of leaves. In the compact thalli a secondary development often takes place by the growth of rhizoid-like internal filaments. They present a hypha-like appearance, running longitudinally for considerable distances. It is not difficult in such compact species to distinguish between superficial cells, whose chief function is assimilation, subjacent cells charged with reserve material, and a core of tissue engaged in the convection of elaborated material from part to part.

An interesting feature of the minute anatomy of Euflorideae, as the Red Algae, exclusive of the Bangiaceae, have been termed, is the existence of the so-called Floridean pit. When a cell divides it is found that there remains in the middle of the new wall a single large circular pit, which persists throughout the life of the cells, becoming more and more conspicuous with the progress of the thickening of the wall. These pits serve to indicate the genetic relationship of adjacent cells, when they form a compact pseudo-parenchyma, notwithstanding the fact that somewhat smaller secondary pits appear later between any contiguous cells. Protoplasmic continuity has been observed in the delicate membrane closing the pit.

Vegetative multiplication occurs only sparingly in Rhodophyceae. Melobesia callithamnioides gives rise to multicellular propagula; (Griffithsia corallina is said to give rise to new individuals, by detaching portions of the thallus from the base of which new attachment organs have already arisen. The spores of Monospora are by some regarded as unicellular propagula. Reproduction is both asexual and sexual. It is noteworthy that although all the members of the group are aquatic no zoospores are produced, a negative character common to them and the Blue-green Algae. As a rule the asexual cells, and the male and female sexual cells arise upon different plants, so that the species may be said to be trioecious. Numerous exceptions, however, occur. Thus in Lemaneaceae asexual spores are unknown; in Batracho-spermum, Bonnemaisonia and Polysiphonia byssoides both kinds of sexual cells appear on the same plant; and in some cases the asexual cells may occur in conjunction with either the male or female sexual cells. The asexual cells are termed tetraspores on account of the usual occurrence of four in each sporangium. What may be termed monospores, bispores and octospores, however, are not unknown. The sporangia may be terminal or intercalated. When they are confined to special branches such branches are spoken of as stichidia. The tetrasrores may arise by the simultaneous division of the contents of a sporangium, when they are arranged tetrahedrally, or they may arise by two successive divisions, in which case the arrangement may be zonate when the spores are in a row, or cruciate when the second divisions are at right angles to the first, or tetrahedral when the second divisions are at right angles to the first and also to one another. Tetraspores are at first naked, but soon acquire a cell-wall and germinate without a period of rest. The male sexual cells are produced singly in the terminal cells of branches. They are spoken of as spermaria. Great numbers of antheridia are usually crowded together, when the part is distinguishable by the absence of the usual red colour. In Polysiphonia they cover the joints of the so-called leaves; in Chondria they arise on flattened dishs; in the more massive forms they arise in patches on the ordinary surface; in a few cases (Gracilaria, Corallina, Galaxaura) they line the walls of conceptacle-like depressions. The female sexual cell is represented by the contents of a cell which is terminal on ordinary or specialized branches. This is the carpogonium: it consists of a neutral portion which contains a nucleus, but in which no oosphere is differentiated, and an elongated tubular portion known as the trichogyne, into which the cytoplasm extends. Fertilization is effected by the passive convection of a spermatium from the antheridium to the trichogyne, to which it adheres, and to which it passes over its nucleus through an open communication set up at the point of contact. The nucleus then passes down the trichogyne and fuses with that of the eeg. This fusion has been observed by Wille in Nemalion multifidim, and by Schmidle in Batrachospermum. It is singular that in the last-named species two nuclei occur regularly in the spermatium. The ventral portion of the carpogonium may be imbedded deep in the thallus in the massive species; the trichogyne, however, always reaches the surface. The first effect of fertilization is the occlusion of the trichogyne from the fertilized carpogonium. The subsequent course of development is characteristic of the Florideae. The carpogonium germinates forthwith, drawing its nourishment almost wholly from the parent plant. The ultimate product in all cases is a number of carpospores, but before this stage is reached the development is different in different subgroups. In Batrachospermum filaments arise from the carpogonium on all sides; in Chantransia and Scinaia on one side only; in Helminthora the filaments are enclosed in a dense mucilage; in Nemalion, prior to the formation of the filaments, a sterile segment is cut off below. In all these cases, however, the end-cells of the filaments each give rise to a carpospore, and the aggregate of such sporiferous filaments is a cystocarp. Again, in the family of the Gelidiaceae, the single filament arising from the carpogonium grows back into the tissue and preys upon the cells of the axis and larger branches, after which the end-cells give rise to carpospores and a diffused cystocarp is formed. In the whole group of the Cryptonemiales the parasitism becomes more marked still. The filaments arising from the carpogonia grow into long thin tubes, which fuse with special cells rich in protoplasm contents; and from these points issue isolated tufts of sporogenous filaments, several of which may form the product of one fertilized female cell. In Naccaria, one of the Gelidiaceae, it is observable that the ooblastema filament, as the tube arising from the fertilized carpogonium has been called, fuses completely with a cell contiguous to the carpogonium before giving rise to the foraging filaments already referred to. This is also the case among Cryptonemiales. In a whole series of Red Algae, the existence or a highly specialized auxiliary cell in the neighbourhood of the carpogonium is a characteristic feature. In the Gigartinales it is already differentiated previous to fertilization; in Rhodymeniales it arises subsequent to fertilization. In the Gigartinales, the filaments which arise from the auxiliary cell may spread and give rise to isolated tufts of sporogenous filaments, as in the Cryptonemiales. In the Rhodymeniales a single tuft arises directly from the auxiliary cell. The carpospores are in all cases bright red naked masses of protoplasm when first discharged. They soon acquire a cell-wall, and germinate without a period of rest. When the cystocarps or segments of cystocarps are formed in the substance of a thallus, the site is marked merely by a swelling of the substance. When the cystocarp is produced externally, it may form a berry-like mass without an envelope, in which case it it known as a favella. In Rhodomelaceae there is a special urn-shaped envelope surrounding the sporogenous filaments. This is a ceramidium.

The attachment of the cell of an ooblastema filament to a cell of the thallus may be effected by means of a minute pore, or the two cells may fuse their contents into one protoplasmic mass. In the latter case, and especially where the union is with a special auxiliary cell, it is of importance to know what happens to the nuclei of the fusing cells. Schmitz was of opinion that in the cases of open union there occurred a fusion of nuclei similar to that which occurs in the sexual union of two cells. He founded his generalization to a large extent upon the observation that in Gloeosiphonia capillaris two cells completely fuse, and that only one nucleus can be detecteo in the fused mass. Oltmanns has recently re-investigated the phenomena in this plant, among others, and has shown that the nucleus of the cell which is being preyed upon recedes to the wall and gradually atrophies. The nucleus of the ooblastema filament dominates the FIG. 5.--Rhodophyceae, variously magnified.

A. Polysiphonia sp., apical region showing leading cell and cutting off of pericentral cell.

B. Polysiphonia sp., transverse section through a branch, and at a, mother-cell of tetraspores.

C. Lomeittaria sp., apex showing growth in length through coordinated growth of many filaments.

D. Delesseria sp., showing apical region with leading cell.

E. Chrysymenia uvaria, axis with swollen leaf-like appendages.

F. Polyzonia sp., branch with leaf-like branches of limited growth.

G. Collithamnson sp., tetrasporangium with spores arranged in a tetrad.

H. Corallina sp., tetrasporangia with zonate arrangement of tetraspores.

K. Nemalion sp., carpogonial and antheridial branches.

L. Batrachospermum sp., trichogyne with spermatia attached; carpospores arising from fertilized carpogonium.

M. Polysiphonia sp., antheridium.

N. Constantinea sp., with flattened leaf-like appendages.

O. Dudresnaya coccinea, fusion of ooblastema filaments with auxiliary cells; a is an axial cell in transverse section with four appendages.

P. Callithamnion corymbosum, a joint cell with carpogonial branch and a, b, two auxiliary cells.

Q. Callithamnion corymbosum, fusion of products of fertilization with auxiliary cells, the nuclei of which a and b retire to the wall.

R. Polysiphonia sp., section through young cystocarp.

(A, C, D, E, F, G, H, K, L, M, P, Q, from Oltmanns, by permission of Gustav Fischer; B, N, O, R, from Engler and Prantl, by permission of Wilhelm Engelmann.)

mass and from it all the nuclei of the carpospores are thus derived. There thus seems to be no justification for believing, as Schmitz taught, that a second sexual act occurs in the life-cycle of these Florideae.

The Bangiales are a relatively small group of Red Algae, to which much of the description now given does not apply. Structurally they are either a plate of cells, as in Porphyra, or filaments, as in Bangia. There is no exclusive apical growth, and the cells divide in all directions. The characteristic pit is also absent. Sexual and asexual reproduction prevail. The male cell is a spermatium, but the female cell bears no such receptive trichogyne as occurs in other Rhodophyceae. After fertilization the equivalent of the oospore divides directly to form a group of carpospores. There is thus a certain resemblance to Euflorideae, but sufficient difference to necessitate their being grouped apart. Fertilization by means of non-motile spermatia and a trichogyne are known among the Fungi in the families Collemaceae any Laboulbeniaceae.

A census of Rhodophyceae is furnished below:--

(1) Bangiaceae--4 families, 9 genera, 58 species.

(2) Nemalioninae--4 families, 33 genera, 343 species.

(3) Gigartininae--3 families, 54 genera, 409 species.

(4) Rhodymeninae--4 families, 92 genera, 602 species. (De Toni's Sylloge Algarum, 1897.)

Limits of the algae.

After this survey of the four groups comprised under Algae it is easier to indicate the variations in the limits of the class as defined by different authorities. To consider the Cyanophyceae first, either the marked contrast in the method of nutrition of the generally colourless Bacteriaceae to that of the blue-green Cyanophyceae is regarded as sufficient ground for excluding Bacteriaceae from algae altogether, notwithstanding their acknowledged morphological affinity with Cyanophyceae, or, in recognition of the incongruity of effecting such a separation, the whole group of the Schizophyta --that is to say, the Cyanophyceae in the narrow sense, together with Bacteriaceae, is included or excluded together. Again, while Conjugatae may be shut out from Chlorophyceae as an independent group co-ordinate with them in rank, the Characeae constitute so aberrant a group that it has even been proposed to raise them as Charophyta to the dignity of a main division co-ordinate with Thallophyta. Similarly, while Diatomaceae may be excluded from among Phaeophyceae, though retained among algae, the Cryptomonadaceae and Peridiniaceae, like Euglena and other Chlorophyceae, may be excluded from Thallophyta and ranged among the flagellate Protozoa. It is doubtful, however, whether the conventional distinction between plants and animals will continue to be urged; and the suggestion of Haeckel that a class Protista should be established to receive the forms exhibiting both animal and plant affinities has much to recommend it on phylogenetic grounds. To adopt a figure, it is probable that the sources from which the two streams of life--animal and vegetable--spring may not be separable by a well-defined watershed at all, but consist of a great level upland, in which the waterways anastomose. Finally, while Chlorophyceae and Phaeophyceae exhibit important affinities, the Rhodophyceae are so distinct that the term ``algae'' cannot be made to include them, except when used in its widest sense.

Phylogeny.

It has been well said that the attempt to classify plants according to their natural affinities is an attempt to construct for them the genealogical tree by which their relationships can be traced. Algae are, however, so heterogeneous a class, of which the constituent groups are so inadequately known, that it is at present futile to endeavour thus to exhibit their pedigree. A synoptical representation of the present state of knowledge would be expressed by a network rather than by a tree. The following table is an adaptation of a scheme devised by Klebs, and indicates the inter-relationships

PROTOZOA Peridiniaceae......Diatomaceae | | Cryptomonadaceae--Hydruraceae--EUPHAEOPHYCEAE Flagellata protomastigina......Bacteriaceae--Endosphaeraceae | CYANOPHYCEAE........Bangiacaeae--EUFLORIDEAE Eugleneae

Chloromonadinae Pleurococcaceae--Endosphaeraceae

Volvocaceae Chlorosphaeraceae CONGUGATAE SIPHONALES

Tetrasporaceae----------Ulvaceae----------CONFERVALES......CHARACEAE

FUNGI BRYOPHYTA

of the various constituent groups. The area included in the thick boundary line represents algae in the widest sense in which the term is used, and the four included areas the four main subdivisions. A continuous line indicates a close affinity, and a dotted line a doubtful relationship.

Alternation of generations.

In comparing algae with the great archegoniate series which has doubtless sprung from them, it is natural to inquire to what extent, if any, they present evidence of the existence of the marked alternation of generations which dominates the life-history of the higher plants. Turning first to the Rhodophyceae, both on account of the high place which they occupy among algae and also the remarkable uniformity in their reproductive processes, it is clear that, as is the case among Archegoniatae, the product of the sexual act never germinates directly into a plant which gives rise to the sexual organs. Even among Bangiaceae the carpospores arise from the fertilized cell by division, while in all other Rhodophyceae the oospore, as it may be called, gives rise to a filamentous structure, varying greatly in its dimensions, epiphytic, and to a large extent parasitic upon the egg-bearing parent plant, and in the end giving rise to carpospores in the terminal cells of certain branches. There is here obviously a certain parallelism with the case of Bryophyta, where the sporogonium arising from the oospore is epiphytic and partially parasitic upon the female plant, and always culminates in the production of spores. Not even Riccia, with its rudimentary sporogonium, has so simple a corresponding stage as Bangia, for, while there is some amount of sterile tissue in Riccia, in Bangia the oospore completely divides to form carpospores. Excluding Bangiaceae, however, from consideration, the Euflorideae present in the product of the development of the oospore like Bryophyta a structure partly sterile and partly fertile. There is, nevertheless, this important difference between the two cases. While the spore of Bryophyta on germination gives rise to the sexual plant, the carpospore of the alga may give rise on germination to a plant bearing a second sort of asexual cells, viz. the tetraspores, and the sexual plant may only be reached after a series of such plants have been successively generated. It is possible, however, that the tetraspore formation should be regarded as comparable with the prolific vegetative reproduction of Bryophyta, and in favour of this view there is the fact that the tetraspores originate on the thallus in a different way from carpospores with which the spores of Bryophyta are in the first place to be compared; moreover, in certain Nemalionales the production of tetraspores does not occur, and the difficulty referred to does not arise in such cases. Altogether it is difficult on morphological grounds to resist the conclusion that Florideae present the same fundamental phenomenon of alternation of generations as prevails in the higher plants. It is by means of the cytological evidence, however, that this problem will finally be solved. As is well known, the dividing nuclei of the cells of the sporophyte generation of the higher plants exhibit a double number of chromosomes, while the dividing nuclei of the cells of the gametophyte generation exhibit the single number. In a fern-plant, for example, which is a sporophyte, every karyokinesis divulges the double number, while in the prothallium, which is the gametophyte generation, the single number appears. The doubling process is provided by the act of fertilization, where an antherozoid with the single number of chromosomes fuses with an oosphere also with the single number to provide a fertilized egg with the double number. The reduction stage, on the other hand, is the first division of the mother-cell of the spore. From egg to spore-mother-cell is sporophyte; from spore-mother-cell to egg is gametophyte. And since this rule has been found to hold good for all the archegoniate series and also for the flowering plants where, however, the gametophyte generation has become so extremely reduced as to be only with difficulty discerned, it is natural that when alternation of generation is stated to occur in any group of Thallophyta it should be required that the cytological evidence should support the view. The genus Nemalion has been recently investigated by Wolfe with the object of examining the cytological evidence. He finds that eight chromosomes appear in karyokinesis in the ordinary thallus cells, but sixteen in the gonimoblast filaments derived from the fertilized carpogonium. Eight chromosomes appear again in the ultimate divisions which give rise to the carpospores. Upon the evidence it would seem therefore that so far as Nemalion is concerned an alternation occurs comparable with that existing in the lower Bryophyta where the sporophyte is relatively small, being attached to and to some extent parasitic upon the gametophyte. Nemalion is, however, one of those Florideae in which tetraspores do not occur. What is the case with those Florideae which have been described as trioecious? If the sporophyte generation is confined to the cystocarp, is the tetrasporiferous plant, as has been suggested, merely a potential gametophyte reproducing by a process analogous to the bud- formation of the Bryophyta? In answer to this question a recent writer, Yamanouchi, states in a preliminary communication that he has found that in Polysiphonia violacea the germinating carpospores exhibit forty chromosomes, and the germinating tetraspores twenty chromosomes. From this it would seem that in this plant reduction takes place in the tetraspore mother- cell, and that the tetrasporiferous plants are sporophytes which alternate with sexual plants. Novel as this result may seem, the tetraspores of Florideae become hereby comparable with the tetraspores of Dictyota, to which reference will be made hereafter. But it is clear that it becomes on this view increasingly difficult to explain the occasional occurrence of tetraspores on male, female and monoecious plants or the role of the carpospores in the life-cycle of Florideae. The results of future research on the cytology of the group will be awaited with interest.

Among Phaeophyceae it is well known that the oospore of Fucaceae germinates directly into the sexual plant, and there is thus only one generation. Moreover, it is known that the reduction in the number of chromosomes which occurs at the initiation of the gametophyte generation in Pteridophyta occurs in the culminating stage of Fucus, where the oogonium is separated from the stalk-cell, so that unless it be contended that the Fucus is really a sporophyte which does not produce spores, and that the gametophyte is represented merely by the oogonium and antheridium, there is no semblance of alternation of generation in this case. The only case among Phaeophyceae which has been considered to point to the existence of such a phenomenon is Cutleria. Here the asexual cells are borne upon the so-called Aglaozonia reptans and the sexual cells upon the plants known as Cutleria. The spores of the Aglaozonia form are known to give rise to sexual plants, and the oospore of Cutleria has been observed to grow into rudimentary Aglaozonia. Latterly, however, as the result of the cytological investigations of Mottler and Lloyd Williams, great advance has been made in our knowledge of the conditions existing in Dictyota. Mottler first observed that a reduction in the number takes place in the mother-cells of the tetraspore. It will be remembered that, as in most Florideae, the male, female and asexual plants are distinct in this genus. Mottler's observation has been confirmed by Lloyd Williams, who has shown, moreover, that the single number occurs in germlings from the tetraspore, and also in the adult stages of all sexual plants, while the double number occurs in germlings from the oospore, and in adult stages of all asexual plants. It is probable, therefore, that we have here a sharp alternation of generations, both generations being, however, precisely similar to the eye up to point of reproduction. Among Chlorophyceae it is often the case that the oospore on germination divides up directly to form a brood of zoospores. In Coleochaete this seems to be preceded by the formation of a minute parenchymatous mass, in each cell of which a zoospore is produced. In Sphaeroplea it is only at this stage that zoospores are formed at all; but in most cases, such as Oedogogonium, Ulothrix, Coleochaete, similar zoospores are produced again and again upon the thallus, and the product of the oospore may be regarded as merely a first brood of a series. It has been held by some, however, that the first brood corresponds to the sporophyte generation of the higher plants, and that the rest of the cycle is the gametophyte generation. Were the case of Sphaeroplea to stand alone, the phenomenon might perhaps be regarded as an alternation of generations, but still only comparable with the case of Bangia, and not the case of the Florideae. But it is difficult to apply such a term at all to those cases in which there intervene between the oospore and the next sexual stage a series of generations, the zoospores of which are all precisely similar.

Polymorphism.

The difficulty of tracing the relationships of algae is largely due to the inadequacy of our knowledge of the conditions under which they pass through the crucial stages of their life-cycle. Of the thousands of species which have been distinguished, relatively few have been traced from spore to spore, as the flowering plants have been observed from seed to seed. The aquatic habit of most of the species and the minute size of many of them are difficulties which do not exist in the case of most seed-plants. From the analogy of the higher plants observers have justly argued that when they have seen and marked the characters of the reproductive organs they have found the plant at the stage when it exhibits its most noteworthy features, and they have named and classified the species in accordance with these observations. While even in such cases it is obvious that interesting stages in the life of the plant may escape notice altogether, in the cases of those plants the reproduction of which is unknown, and which have been named and placed on the analogy of the vegetative parts alone, there is considerable danger that a plant may be named as a distinct species which is only a stage in the life of another distinct and perhaps already known species. To take an example, Lemanea and Batrachospermum are Florideae which bear densely-whorled branches, but which, on the germination of the carpospore, give rise to a laxly-filamentous, somewhat irregularly-branched plant, from which the ordinary sexual plants arise at a later stage. This filamentous structure has been attributed to the genus Chantransia, which it greatly resembles, especially when, as is said to be the case in Batrachospermum, it bears similar monospores. The true Chantransia, however, bears its own sexual organs as well as monospores. To the specific identity of Haplospora globosa and Scaphospora speciosa, and of Cutleria muitifida and Aglaozonia reptans, reference has already been made. Again, many Green Algae--some unicellular, like Sphaerella and Chlamydomonas; some colonial forms, like Volvox and Hormotila; some even filamentous forms, like Ulothrix and Stigeoclonium-- are known to pass into a condition resembling that of a Palmella, and might escape identification on this account.

It is, on the other hand, a danger in the opposite sense to conclude that all Chantransia species are stages in the life-cycle of other plants, and, similarly, that all irregular colonial forms, like Palmella, represent phases in the life of other Green Algae. Long ago Kutzing went so far as to express the belief that the lower algae were all capable of transformations into higher forms, even into moss-protonemata. Later writers have also thought that in all four groups of algae transformations of a most far-reaching character occur. Thus Borzi finds that Protoderma viride passes through a series of changes so varied that at different times it presents the characters of twelve different genera. Chodat does not find so general a polymorphism, but nevertheless holds that Raphidium passes through stages represented by Protococcus, Characium, Dactylococcus and Sciadium. Klebs has, however, recently canvassed the conclusions of both these investigators; and as the result of his own observations declares that algae, so far from being as polymorphic as they have been described, vary only within relatively narrow limits, and present on the whole as great fixity as the higher plants. It certainly supports his view to discover, on subjecting to a careful investigation Botrydium granulatum, a siphonaceous alga whose varied forms had been described by J. Rostafinski and M. Woronin, that these authors had included in the life-cycle stages of a second alga described previously by Kutzing, and now described afresh by Klebs as Protosiphon bolryoides. In Botrydium the chromatophores are small, without pyrenoids, and oil-drops are present; in Protosiphon the chromatophores form a net-work with pyrenoids, and the contents include starch. Klebs insists that the only solution of such problems is the subjection of the algae in question to a rigorous method of pure culture. It is interesting to learn that G. Senn, pursuing the methods described by Klebs, has confirmed Chodat's observation of the passage of Raphidium into a Dactylococcus-stage, although he was unable to observe further metamorphosis. He has also seen Pleurococcus viridis dividing so as to form a filament, but has not succeeded in seeing the formation of zoospores as described by Chodat. While, therefore, there is much evidence of a negative character against the existence of an extensive polymorphism among algae, some amount of metamorphosis is known to occur. But until the conditions under which a particular transformation takes place have been ascertained and described, so that the observation may be repeated by other investigators, scant credence is likely to be given to the more extreme polymorphistic views.

Physiology.

In comparison with the higher plants, algae exhibit so much simplicity of structure, while the conditions under which they grow are so much more readily controlled, that they have frequently been the subject of physiological investigation with a view chiefly to the application of the results to the study of the higher plants. (See PLANTS: Physiology of.) In the literature of vegetable physiology there has thus accumulated a great body of facts relating not only to the phenomena of reproduction, but also to the nutrition of algae. With reference to their chemical physiology, the gelatinization of the cell-wall, which is so marked a feature, is doubtless attributable to the occurrence along with cellulose of pectic compounds. There is, however, considerable variation in the nature of the membrane in different species; thus the cell-wall of Gedogonium, treated with sulphuric acid and iodine, turns a bright blue, while the colour is very faint in the case of Spirogyra, the wall of which is said to consist for the most part of pectose. While starch occurs commonly as a cell-content in the majority of the Green Algae no trace of it occurs in Vaucheria and some of its allies, nor is it known in the whole of the Phaeophyceae and Rhodophyceae. In certain Euphaeophyceae bodies built up of concentric layers, and attached to the chromatophores, were described by Schmitz as phaeophycean-starch; they do not, however, give the ordinary starch reaction. Other granules, easily mistaken for the ``starch'' granules, are also found in the cells of Phaeophyceae; these possess a power of movement apart from the protoplasm, and are considered to be vesicles and to contain phloroglucin. The colourless granules of Florideae, which are supposed to constitute the carbohydrate reserve material, have been called floridean-starch. A white efflorescence which appears on certain Brown Algae (Saccorhiza bulbosa, Laminaria saccharina), when they are dried in the air, is found to consist of mannite. Mucin is known in the cell-sap of Acetabularia. Some Siphonales (Codium) give rise to proteid crystalloids, and they are of constant occurrence among Florideae. The presence of tannin has been established in the case of a great number of freshwater algae.

Colouring matters.

By virtue of the possession of chlorophyll all algae are capable of utilizing carbonic acid gas as a source of carbon in the presence of sunlight. The presence of phycocyanin, phycophaein and phycoerythrin considerably modifies the absorption spectra for the plants in which they occur. Thus in the case of phycoerythrin the maximum absorption, apart from the great absorption at the blue end of the spectrum, is not, as in the case where chlorophyll occurs alone, near the Fraunhofer line B, but farther to the right beyond the line D. By an ingenious method devised by Engelmann, it may be shown that the greatest liberation of oxygen, and consequently the greatest assimilation of carbon, occurs in that region of the spectrum represented by the absorption bands. In this connexion Pfeffer points out that the penetrating power of light into a clear sea varies for light of different colours. Thus red light is reduced to such an extent as to be insufficient for growth at a depth of 34 metres, yellow light at a depth of 177 metres and green light at 322 metres. It is thus an obvious advantage to Red Algae, which flourish at considerable depths, to be able to utilize yellow light rather than the red, which is extinguished so much sooner. The experiment of Engelmann referred to deserves to be mentioned here, if only in illustration of the use to which algae have been put in the study of physiological problems. Engelmann observed that certain bacteria were motile only in the presence of oxygen, and that they retained their motility in a microscopic preparation in the neighbourhood of an algal filament when they had come to rest elsewhere on account of the exhaustion of oxygen. After the bacteria had all been brought to rest by being placed in the dark, he threw a spectrum upon the filament, and observed in what region the bacteria first regained their motility, owing to the liberation of oxygen in the process of carbon-assimilation. He found that these places corresponded closely with the region of the absorption band for the algae under experiment.

Although algae generally are able to use carbonic acid gas as a source of carbon, some algae, like certain of the higher plants, are capable of utilizing organic compounds for this purpose. Thus Spirogyra filaments, which have been denuded of starch by being placed in the dark, form starch in one day if they are placed in a 10 to 20% solution of dextrose. According to T. Bokorny, moreover, it appears that such filaments will yield starch from formaldehyde when they are supplied with sodium oxymethyl sulphonate, a salt which readily decomposes into formaldehyde and hydrogen sodium sulphite, an observation which has been taken to mean that formaldehyde is always a stage in the synthesis of starch. With reference to the assimilation of nitrogen, it would seem that algae, like other green plants, can best use it when it is presented to them in the form of a nitrate. Some algae, however, seem to flourish better in the presence of organic compounds. In the case of Scenedesmus acutus it is said that the alga is unable to take up nitrogen in the form of a nitrate or ammoniacal salt, and requires some such substance as an amide or a peptone. On the other hand, it has been held by Bernhard Frank and other observers that atmospheric nitrogen is fixed by the agency of Green Algae in the soil: (For the remarkable symbiotism between algae and fungi see FUNGI and LICHENS.)

Habitat.

Most algae, particularly Phaeophyceae and Rhodophyceae, spend the whole of the life-cycle immersed in water. In the case of the freshwater algae, however, belonging to the Chlorophyceae and Cyanophyceae, although they required to be immersed during the vegetative period, the reproductive cells are often capable of resisting a considerable degree of desiccation, and in this condition are dispersed through great distances by various agencies. Again, as is well known, many species of marine algae growing in the region between the limits of high and low water are so constituted that they are exposed to the air twice a day without injury. The occurrence of characteristic algae at different levels constituting the zones to which reference has already been made, is probably in part an expression of the fact that different species vary in the capacity to resist desiccation from exposure. Thus Laminaria digitata, which characterizes the lowest zone, is only occasionally exposed at all, and then only for short periods of time. On the other hand, Pelvetia canaliculata, which marks the upper belt, is exposed for longer periods, and during neap tides may not be reached by the water for many days. Algae of more delicate texture than either Fucaceae or Laminariaceae also occur in the region exposed by the ebb of the tide, but these secure their exemption from desiccation either by retaining water in their meshes by capillary attraction, as in the case of Pilayella, or by growing among the tangles of the larger Fucaceae, as in the case of Polysiphonia fastigiata, or by growing in dense masses on rocks, as in the case of Laurencia pinnatifida. Such a species as Delesseria sanguinea or Callophyllis laciniata would on the contrary run great risk by exposure for even a short period. A few algae approach the ordinary terrestrial plants in their capacity to live in a sub-aerial habitat subject only to such occasional supphes of water as is afforded by the rainfall. Of this nature are some of the species of Vaucheria. A very few species, like Chroolepus, which grows on rock surfaces, are comparable with the land plants which have been termed xerophilous.

Plankton.

The great majority of the aquatic algae, both freshwater and marine, are attached plants. Some, however, are wanderers, either swimming actively with the aid of cilia, or floating inertly as the result of a specific weight closely approaching that of the medium. To the aggregate of such forms, both animal and vegetable, the term plankton has been applied, and the investigation of the vegetable plankton, both freshwater and marine, has been pursued in recent times with energy and success. The German Plankton Expedition of 1889 added greatly to our knowledge of the floating vegetable life of the North Atlantic Ocean, while many laboratories established on the shores of inland seas and lakes have rendered a similar service in the case of our freshwater phyto-plankton. The quantitative estimate of the amount of this flora has revealed its enormous aggregate amount and therefore its great importance in the economy of oceanic and lacustrine animal life. The organisms constituting this plankton are mostly unicellular, often aggregated together in colonies, and the remarkable structure which they exhibit has added a new chapter to the story of adaptation to environment. The families Diatomaceae, Peridiniaceae and Protococcaceae are best represented in the pelagic plankton, while in addition the Volvocaceae are an important element in freshwater plankton.

Benthos.

The great majority of algae, however, grow like land-plants attached to a substratum, and to these the term benthos is now generally applied. While the root of land-plants serves for the double purpose of attachment and the supply of water, it is attachment only that is usually sought in the case of algae. Immersed as they usually are in a medium containing in solution the inorganic substances which they require for their nutrition, the absorption of these takes place throughout their whole extent. The elaborate provision for the conduct of water from part to part which has played so important a role in the morphological development of land plants is entirely wanting in algae, such conducting tissues as do exist in the larger Phaeophyceae and Rhodophyceae serving rather for the convection of elaborated organic substance, and being thus comparable with the phloem of the higher plants. The attachment organ of algae is thus more properly called a holdfast, and is found to be of very varied structure. It generally takes the form of a single flattened disc as in the Fucaceae, or a group of finger- like processes as in Laminariaceae, or a tuft of filaments as in many instances. When the attachment is in sand or mud, it often simulates the appearance of a true root as in Chara or Caulerpa. It is clear that where the bottom of a lake or sea consists of oozy mud or shifting sand, it is impossible for algae to secure a foothold. Thus a rock emerging from a sandy beach may often be observed to stand covered with vegetation like an oasis in a desert. The rapidity with which walls, piles and pontoons--stone, wood and iron--become covered with marine plants is well known, while the discovery of some effective means of preventing the fouling of the bottoms of ships by the growth of algae would be hailed as a boon by shipowners. While rocks and boulders are the favoured situation for the growth of marine algae, those which readily disintegrate, like the coarser sandstones, are naturally less favoured than the hard and resistant. A large number of algae again live as epiphytes or endophytes. In the case of the freshwater species the host-plants are mostly species of aquatic Graminaceae, Naiadaceae or Nymphaeaceae. In the case of marine algae, the hosts are chiefly the larger Phaeophyceae and Rhodophyceae. A bed of Zostera near the level of low water is, however, on the British coast a favourite collecting ground for the smaller red and brown epiphytes. Of endophytes a distinction must be made between those which occupy the cell-wall only and those which perforate the cells, bringing about their destruction. There can be little doubt that in some cases the epiphytism approaches parasitism. In one case described by Kuckuck the chromaphores of the infesting algae are absent, a circumstance which points to a complete parasitism. Allusion has already been made to the peculiar habit of the shell-boring algae.

Habit.

In many algae certain branches of limited growth bear a remarkable resemblance to leaves. The Characeae among freshwater algae and the Sargassaceae among marine algae might be cited as examples. Surveying the whole range of algae life, Oltmanns distinguishes bush-forms, whip- forms, net-forms, leaf-forms, sack-forms, dorsi-ventral forms, and cushions, plates and crusts. The similarity of outline in many species to that of trees and shrubs will strike any one who examines algae mounted for the herbarium. Cladophora and Bryopsis among monosiphonous forms, Chara, Polysiphonia, Ceramium and Cystoseira among larger algae, are illustrations of this. The whip-forms are represented by Spirogyra, Chaetomorpha, Scytosiphon, Nemalion, Himanthalia and Chorda. Net-forms are found in Hydrodictyon and Microdictyon. The leaf-forms are very varied and owe their existence to the advantage accruing from the exposure of a large surface to the influence of the light. In some cases such as Delesseria, Neurymenia, Fucus, Alaria, the leaf-like structure is provided with a strengthening mid-rib, and when as in Delesseria it is also richly veined the resemblance to the leaf of a flowering plant is striking. Laminaria, Padina, Cutleria, Punctaria, Iridaea, Ulva, Porphyra, are leaf-like with a rigidity varying from a fleshy lamina to the thin and pliable. Agarum, Claudea and Struvea are leaf-forms which are perforated like Aldrovanda among flowering plants. Enteromorpha, Asperococcus and Adenocystis are sack-forms. Dorsi-ventral algae are rare. Leveillea jungermanneoides bears a remarkable resemblance to a leafy liverwort. In the next group of forms the simplest are crusts attached to the substratum throughout their extent, and growing at the margin. Such are Myrionema, Ralfsia, Melobesia and Hildebrandtia. Others are attached throughout their extent, but also grow vertical filaments so as to form a velvety pile. Such are Coleochaete, Ochlochaete, Elachistea, Ascocyclus and Rhododermis. Peysonellia squamaria, Melobesia lichenoides, Leathesia difformis are forms which are not attached throughout but grow in plates like the foliaceous lichens.

Ecology.

When it is sought to consider algae with a view to the correlation of the external form to the conditions of life, a subject the study of which under the name of ecology has been latterly pursued with great success among land plants, it is difficult as yet to arrive at generalizations which are trustworthy. Among land plants, as is well known, similarity of environment has often called forth similar adaptations among plants of widely separated families. The similarity of certain xerophilous Euphorbiaceae to Cactaceae is a ready illustration of this phenomenon. From what has been already said it is evident that among algae also strikingly similar forms exist in widely different groups. Instances might be multiplied. Compare, for example, the blue-green Gloeocapsa with the green Gloeocystis, the red Batrachospermum with the green Draparnaldia, the red Corallina with the green Cymopolia, the green Enteromorpha with the brown Asperococcus, the green Ulva with the red Porphyra, the red Nemalion with the brown Castagnea, and so on. But on the one hand similar forms seem to grow often under different conditions, while on the other hand different forms flourish under the same conditions. The conceivable variations in the conditions which would count in algal life are variations in the chemical character of the water--whether fresh, brackish or salt; or in the rate of movement of the water, whether relatively quiet, or a stream or a surf; or in the degree of illumination with the depth and transparency of the water. But the laws which determine the associations of various algae under one environment are as yet little understood. The occurrence of a plentiful mucilage in many freshwater forms is, however, doubtless a provision against desiccation on exposure. The fine subdivision of filamentous and net-forms is similarly a provision for easy access of water and light to all parts. The calcareous deposits in Characeae, Corallinaceae and Siphonaceae are at once a protection against attack and a means of support. The whip-forms would seem to be designed to resist injury from surf or current. The vesicles of Fucaceae and Laminariaceae prevent the sinking of the bulkier forms. But why certain Fucaceae favour certain zones in the littoral region, why certain epiphytes are confined to certain hosts, why Red and Brown Algae are not better represented in fresh water Or Green Algae in salt,--these are problems to which it is difficult to find a ready answer.

Uses.

Algae cannot be regarded as directly important in the industries. On the coasts of Europe marine algae detached by the autumnal gales are commonly carted on to the land as a convenient manure. Porphyra laciniata and Rhodymenia palmata are locally used as food, the latter being known as dulse. Agar-agar is a gelatinous substance derived from an eastern species of Gracilaria. The ash of seaweeds, known in Scotland as kelp, and in Brittany as varec, was formerly used as a source of iodine to a greater extent than is at present the case.

Occurence in the rocks.

Excepting where the thallus is impregnated with silica, as in Diatomaceae, or carbonate of lime, as in Corallinaceae, Characeae and some Siphonales, it is perhaps not surprising that algae should not have been extensively preserved in the fossil form. Considering, however, that it is generally believed that Bryophyta and vascular plants are descended from an algal ancestry, it is natural to suppose that, prior to the luxuriant vegetable growths of the Carboniferous period, there must have existed an age of algae. It was doubtless this expectation that has led to the description of a number of Silurian and Devonian remains as algae upon what is now regarded as inadequate evidence. The geologic record is, as perhaps is to be expected, exceedingly poor, except as regards the calcareous Siphonales, which are well represented at various horizons, from the Silurian to the Tertiary; even the Diatomaceae, which are found in great quantities in the Tertiary deposits, do not occur at all earlier than the chalk. It is believed, however, that the Devonian fossil, Nematophycus, is a Laminarian alga, but it is not until the late Secondary and the Tertiary formations that fossil remains of algae become frequent. (See PALAEOBOTANY.)

The subjoined list includes the larger standard works on algae, together with a number of papers to which reference is made in this article. For a detailed catalogue of Algological literature, see the ``Bibliotheca Phycologica'' in de Tonii's Syllope Algarum, vo1. i. (1889), with the addendum thereto in vol. iv. (1897) of the same work. GENERAL.--J. G. Agardh, Species, genera et ordines Algarum (vols. i-iii., Algernes Systematik (Lund, 1872-1899); J. E. Areschoug, ``Observationes Phycologicae,'' Nova Acta reg. soc. sci. Upsaliensis (Upsala, 1866-1875); F. F. Blackman, ``The Primitive Algae and the Flagellata,'' Ann. of Botany (vol. xiv., Oxford, 1900); E. Bornet and G. Thuret, Notes agologiques (fasc. i.-ii., Paris, 1876-1880); P. A. Dangeard, ``Recherches sur les algues inferieures,'' Ann. des sci. naturelles, Bot. (vol. vii., Paris, 1888); A. Derbes and A. J. J. Solier, Momoire de la physiologie des algues (Paris, 1856); J. B. de Toni, Sylloge Algarum---vol. i. Chlorophyceae, vol. ii. Bacillariaceae, vol. iii. Fucoideae, vol. iv. Florideae (Padua, 1889-1900); P. Falkenberg, ``Die Algen im weitesten Sinne,'' Schenk's Handbuch der Botanik (vol. ii., 1882); W. G. Farlow, Morine Algae of New England (Washington, 1881); W. H. Harvey, Phycologia Britannica (4 vols., London, 1846-1855); Nereis Boreali-Americana (3 pts., Washington, 1851-1858); Phycologia Australica (5 vols., London, 1858-1863); F. Hauck, ``Die Meeresalgen Deutschlands und Osterrichs,'' Rabenhort's Kryptogamen-Flora (Leipzig, 1885); F. R. Kjellman, The Algae of the Arctic Sea (Stockholm, 1883); F. T. Kutzing, Tabulae Phycologicae (19 vols., Nordhausen, 1845-1869); P. Kuckuck, Beitrage zur Kenntniss der Meercsalgen (Kiel and Leipzig, 1897-1899); G. Murray, Phycological Memoirs (London, 1892-1895) Naegeli, Die neueren Algensysteme (Zurich, 1847); F. Oltmanns, Morphologie und Biologie der Algen (Jena, Band i. 1904, Band ii. 1905); N. Pringsheim, ``Beitrage zur Morphologie der Meeresalgen,'' Abhand. Konigl. Akad. der Wissensch. (Berlin, 1862); J. Reinke, Atlas deutscher Meeresalgen (Berlin, 1889-1892); F. Schutt, Das Pflanzenleben der Hochsee (Leipzig, 1893); J. Stackhouse, Nereis britannica (ed. i., Bath, 1801; ed. ii., Oxford, 1816); G. Thuret and E. Bornet, Etudes phycologiques (Paris, 1878); D. Turner, Historia Fucorum (4 vols., London, 1808-1819); G. Zanardini, Iconographia Phycologia Adriatica (Venice, 1860-1876).

1. CYANOPHYCEAE.--E. Bornet and Ch. Flahault, ``Revision des Nostocacees heterocystees,'' Ann. des sc. naturelles, Bot.(vols. iii.-vii., Paris, 1887-1888); M. Gomont, ``Monographic des Oscillariees,'' Ann. des sc. naturelles, Bot. (vols. xv.-xvi., Paris, 1893); Hegler, ``Uber Kerntheilungserscheinungen,'' Ref. Botan. Centralbl. (vol. lxiv., Cassel, 1895); O. Kirchner, ``Schizophyceae'', in Engler and Prantl's Pflanzenfamilien (Leipzig, 1900).

2. CHLOROPHYCEAE.--A. Borzi, ``Studi anamorfici di alcune alghe verdi,'' Bull. Soc. Bot. Ital. in N. Giorn. Bot. Ital. (vol. xxii., Pisa, 1890); F. F. Blackman and A. G. Tansley, A Revision of the Classification of the Green Algae, reprinted from the New Phytologist (vol. i., London, 1903); K. Bohlin, ``Studier ofver nagra slagten af alggruppen confervales Borzi,'' Bihang till K. Svenska vel. akad. Handlinger (Bd. xxiii. afd. 3, 1897);--Ufkasttill, De grona algernas och arkegomiaternas bylogeni (Upsala, 1901); R. Chodat, ``On the Polymorphism of the Green Algae,'' Ann. of Botany (vol. xi., Oxford, 1897); M. C. Cooke, British Freshwater Algae (2 vols., London, 1884), British Desmids (London, 1887); G. Klebs, Die Bedingungen der Fortpflanzung bei einigen Algen und Pilzen (Jena, 1896); A. Luther, ``Uber Chlorosaccus, n.g.'' Bihang till K. Svenska vel. akad. Handlinger (Bd. xxiv. afd. 3, 1899); H. Grat zu Solms-Laubach, ``Monograph of the Acetabulariaceae,'' Trans. Linn. Soc. (Lond.) Bot. (London, 1895); N. Wille, ``Chlorophyceae'', in Engler and Prantl's Pflanzenfamilien (Leipzig, 1897).

3. PHAEOPHYCEAE.--E. A. L. Batters, ``On Ectocarpus secundus,'' Grevillea (vol. xxi., London, 1893); G. Berthold, ``Die geschlechliche Fortpflanzung der eigentlichen Phaeosooreen,'' Mitth. Zool. Stat. Neapel (vol. ii., Leipzig, 1881); G. Brebner, ``On the Classification of the Tilopteridaceae,'' Proc. Bristol Nat. Soc. (vol. viii., Bristol, 1896-1897); A. H. Church, ``On the Polymorphy of Cutleria multiflda,'' Ann. of Botany (vol. xii., Oxford, 1898); J. B. Farmer esnd J. Ll. Williams, ``Contributions to our Knowledge of the Life- history and Cytology of Fucaceae,'' Phil. Trans. Roy. Soc. (vol. cxc., London, 1898); E. Janczewski, ``Observations sur l'accroissement du thalle des Phaeosporees,'' Mem. soc. nat. de sc. (Cherbourg, 1895); F. R. Kjellmann, ``Phaeophyceae,'' in Engler and Prantl's Pflanzenfamilian (Leipzig, 1897); F. Oltmanns, ``Beitrage zur Kenntniss der Fucaceen,'' Bibliotheca botanica, xiv. (Cassel, 1889); C. Sauvageau, ``Observations relatives a la sexualite des Phaeosporees,'' Journal de botanique (vol. x., Paris, 1896); E. Strasburger, ``Kerntheilung und Befruchtung bei Fucus,'' Cytologische Studien (Berlin, 1897); F. Schutt, Die Peridinien der Plankton-Expedition (Kiel and Leipzig, 1895); R. Valiante, Le Cystoseirae del Golfo di Napoli (Leipzig, 1883); J. Ll. Williams, ``On the Antherozoids of Dictyota and Taonia,'' Ann. of Botany (vol. xi., Oxford, 1897).

4. RHODOPHYCEAE.--G. Berthold, ``Die Bangiacen des Golfes von Neapel,'' Mitth. Zool. Stat. Neapel (Naples, 1882); F. Oltmanns, ``Zur Entwickelungsgeschichte der Florideen,'' Botanische Zeitung (1898); R. W. Philligs, ``The Development of the Cystocarp in Rhodymeniales,'' i. and ii., Annals of Botany (vols. xi. xii., Oxford. 1897-1898); F. Schmitz, ``Untersuchungen uber die Befruchtung der Florideen,'' Sitzungsber. der konigl. Akad.der Wissensch. (Berlin, 1883); ``Kleinere Beitrage zur Kenntniss der Florideen,'' La Nuova Notarisia, 1892-1894; F. Schmitz, P. Falkenberg, P. Hauptfleisch, ``Rhodophyceae,'' in Engler and Prantl's Pflanzenfamilien (1897); W. Schmidle, ``Die Befruchtung, Keimung und Haarinsertion von Batrachospermum,'' Bot. Zeitung.. (1899); Sirodot, Les Batrachospermes (Paris, 1884); N. Wille, ``Uber die Befruchtung bei Nemalion multifidum,'' Ber. d. deutschen bot. Gesellsc. Band xii. (Berlin, 1894); J. J. Wolfe, ``Cytological Studies on Nemalion,'' Annals of Botany (vol. xviii., Oxford, 1904); S. Yamanouchi, ``The Life- History of Polysiphonia violacea,'' Botanical Gazette (vol. xli., Chicago, 1906). (R. W. P.)

ALGARDI, ALESSANDRO (1602-1654), Italian sculptor, was born at Bologna in 1602. While he was attending the school of the Caracci his preference for the plastic art became evident, and he placed himself under the instruction of the sculptor Conventi. At the age of twenty he was brought under the notice of Duke Ferdinand of Mantua, who gave him several commissions. He was also much employed about the same period by jewellers and others in modelling in gold, silver and ivory. After a short residence in Venice he went to Rome in 1625 with an introduction from the duke of Mantua to the pope's nephew, Cardinal Ludovisi, who employed him for a time in the restoration of ancient statues. The death of the duke of Mantua left him to his own resources, and for several years he earned a precarious maintenance from these restorations and the commissions of goldsmiths and jewellers. In 1640 he executed for Pietro Buoncompagni his first work in marble, a colossal statue of San Filippo Neri, with kneeling angels. Immediately after, he produced a similar group, representing the execution of St Paul, for the church of the Barnabite Fathers in Bologna. These works, displaying great technical skill, though with considerable exaggeration of expression and attitude, at once established Algardi's reputation, and other commissions followed in rapid succession. The turning point in Algardi's fortune was the accession of Innocent X., of the Bolognese house of Panfili, to the papal throne in 1644. He was employed by Camino Panfili, nephew of the pontiff, to design the Villa Doria Panfili outside the San Pancrazio gate. The most important of Algardi's other works were the monument of Leo XI., a bronze statue of Innocent X. for the capitol, and, above all, La Fuega d'Attila, the largest alto-relievo in the world, the two principal figures being about 10 ft. high. In 1650 Algardi met Velasquez, who obtained some interesting orders for his Italian companion in Spain. Thus there are four chimneys by Algardi in the palace of Aranjuez, where also the figures on the fountain of Neptune were executed by him. The Augustine monastery at Salamanca contains the tomb of the count and countess de Monterey, which was also the work of Algardi. From an artistic point of view, he was most successful in his portrait-statues and groups of children, where he was obliged to follow nature most closely. In his later years he became very avaricious and amassed a great fortune. He died in Rome on the 10th of June 1654.

See Le arti di Bologna disegnate da A. Caracci ed intagliati da S. Giulini, con' assistenza d' Alessandro A. Algardi (1740).

ALGAROTH, POWDER OF, a basic chloride of antimony. It was known to Basil Valentine, and was used medicinally by the Veronese physician Victor Algarotus about the end of the 16th century. Its composition is probably Sb4O5Cl2, and it may be prepared by the addition of much water to a solution of antimony chloride; a bulky amorphous precipitate being formed, which, on standing, gradually becomes crystalline. It is soluble in hydrochloric acid and tartaric acid, but insoluble in alcohol.

On its composition and preparation see E. Peligot, Annalen, 1847, lxiv. 280; L. Schaffer, Annalen, 1869, clii. 314; and R. W. E. MacIvor, Chem. News, 1875, xxxii. 229.

ALGAROTTI, FRANCESCO, COUNT (1712-1764), Italian philosopher and writer on art, was born on the 11th of December 1712 at Venice, and died at Pisa in 1764. He studied at Rome and Bologna, and at the age of twenty went to Paris, where he enjoyed the friendship of Voltaire and produced his great work Neutonianismo per le dame, a work on optics. Voltaire called him his cher cygne de Padoue. Returning from a journey to Russia, he met Frederick the Great who made him a count of Prussia (1740) and court chamberlain (1747). Augustus III. of Poland honoured him with the title of councillor. In 1754, after seven years' residence partly in Berlin and partly in Dresden, he returned to Italy, living at Venice and then at Pisa, where he died on the 3rd of May 1764. Frederick the Great erected to his memory a monument on the Campo Santo at Pisa. He was a man of wide knowledge, a connoisseur in art and music, and the friend of most of the leading authors of his time. His chief work on art is the Saggi sopra le belle arti (``Essays on the Fine Arts''). Among his other works may be mentioned Poems, Travels in Russia, Essay on Painting, Correspondence.

The best complete edition with biography was published by D. Michelessi (1791-1794).

ALGARVE, or ALGARVES, an ancient kingdom and province in the extreme S. of Portugal, corresponding with the modern administrative district of Faro, and bounded on the N. by Alemtejo, E. by the Spanish province of Huelva, and S. and W. by the Atlantic Ocean. Pop. (1900) 255,191; area, 1937 sq. m. The greatest length of the province is about 85 m. from E. to W.; its average breadth is about 22 m. from N. to S. The Serra de Malhao and the Serra de Monchique extend in the form of a crescent across the northern part of the province, and, sweeping to the south-west, terminate in the lofty promontory of Cape St Vincent, the south-west extremity of Europe. This headland is famous as the scene of many sea-fights, notably the defeat inflicted on the Spanish fleet in February 1797 by the British under Admiral Jervis, afterwards Earl St Vincent. Between the mountainous tracts in the north and the southern coast stretches a narrow plain, watered by numerous rivers flowing southward from the hills. The coast is fringed for 30 m. from Quarteira to Tavira, with long sandy islands, through which there are six passages, the most important being the Barra Nova, between Faro and Olinao. The navigable estuary of the Guadiana divides Algarve from Huelva, and its tributaries water the western districts. From the Serra de Malhao flow two streams, the Silves and Odelouca, which unite and enter the Atlantic below the town of Silves. In the hilly districts the roads are bad, the soil unsuited for cultivation, and the inhabitants few. Flocks of goats are reared on the mountain-sides. The level country along the southern coast is more fertile, and produces in abundance grapes, figs, oranges, lemons, olives, almonds, aloes, and even plantains and dates. The land is, however, not well suited for the production of cereals, which are mostly imported from Spain. On the coast the people gain their living in great measure from the fisheries, tunny and sardines being caught in considerable quantities. Salt is also made from sea-water. There is no manufacturing or mining industry of any importance. The harbours are bad, and almost the whole foreign trade is carried on by ships of other nations, although the inhabitants of Algarve are reputed to be the best seamen and fishermen of Portugal. The chief exports are dried fruit, wine, salt, tunny, sardines and anchovies. The only railway is the Lisbon-Faro main line, which passes north-eastward from Faro, between the Monchique and Malhao ranges. Faro (11,789), Lagos (8291), Loule (22,478), Monchique (7345), Olhao (10,009), Silves (9687) and Tavira (12,175), the chief towns, are described in separate articles.

The name of Algarve is derived from the Arabic, and signifies a land lying to the west. The title ``king of Algarve,'' held by the kings of Portugal, was first assumed by Alphonso III., who captured Algarve from the Moors in 1253.

ALGAU, or ALLGAU, the name now given to a comparatively small district forming the south-western corner of Bavaria, and belonging to the province of Swabia and Neuburg, but formerly applied to a much larger territory, which extended as far as the Danube on the N., the Inn on the S. and the Lech on the W. The Algau Alps contain several lofty peaks, the highest of which is Madelegabel (8681 ft.). The district is celebrated for its cattle, milk, butter and cheese.

ALGEBRA (from the Arab. af-jebr wa'l-muqabala, transposition and removal [of terms of an equation], the name of a treatise by Mahommed ben Musa al-Khwarizmi), a branch of mathematics which may be defined as the generalization and extension of arithmetic.

The subject-matter of algebra will be treated in the following article under three divisions:---A. Principles of ordinary algebra; B. Special kinds of algebra; C. History. Special phases of the subject are treated under their own headings, e.g. ALGEBRAIC FORMS; BINOMIAL; COMBINATORIAL ANALYSIS; DETERMINANTS; EQUATION; CONTINUED FRACTION; FUNCTION; GROUPS, THEORY OF; LOGARITHM; NUMBER; PROBABILITY; SERIES.

A. PRINCIPLES OF ORDINARY ALGEBRA

1. The above definition gives only a partial view of the scope of algebra. It may be regarded as based on arithmetic, or as dealing in the first instance with formal results of the laws of arithmetical number; and in this sense Sir Isaac Newton gave the title Universal Arithmetic to a work on algebra. Any definition, however, must have reference to the state of development of the subject at the time when the definition is given.

2. The earliest algebra consists in the solution of equations. The distinction between algebraical and arithmetical reasoning then lies mainly in the fact that the former is in a more condensed form than the latter; an unknown quantity being represented by a special symbol, and other symbols being used as a kind of shorthand for verbal expressions. This form of algebra was extensively studied in ancient Egypt; but, in accordance with the practical tendency of the Egyptian mind, the study consisted largely in the treatment of particular cases, very few general rules being obtained.

3. For many centuries algebra was confined almost entirely to the solution of equations; one of the most important steps being the enunciation by Diophantus of Alexandria of the laws governing the use of the minus sign. The knowledge of these laws, however, does not imply the existence of a conception of negative quantities. The development of symbolic algebra by the use of general symbols to denote numbers is due to Franciscus Vieta (Francois Viete, 1540-1603).This led to the idea of algebra as generalized arithmetic.

4. The principal step in the modern development of algebra was the recognition of the meaning of negative quantities. This appears to have been due in the first instance to Albert Girard (1595-1632), who extended Vieta's results in various branches of mathematics. His work, however, was little known at the time, and later was overshadowed by the greater work of Descartes (1596-1650).

5. The main work of Descartes, so far as algebra was concerned, was the establishment of a relation between arithmetical and geometrical measurement. This involved not only the geometrical interpretation of negative quantities, but also the idea of continuity; this latter, which is the basis of modern analysis, leading to two separate but allied developments, viz. the theory of the function and the theory of limits.

6. The great development of all branches of mathematics in the two centuries following Descartes has led to the term algebra being used to cover a great variety of subjects, many of which are really only ramifications of arithmetic, dealt with by algebraical methods, while others, such as the theory of numbers and the general theory of series, are outgrowths of the application of algebra to arithmetic, which involve such special ideas that they must properly be regarded as distinct subjects. Some writers have attempted unification by treating algebra as concerned with functions, and Comte accordingly defined algebra as the calculus of functions, arithmetic being regarded as the calculus of values.

7. These attempts at the unification of algebra, and its separation from other branches of mathematics, have usually been accompanied by an attempt to base it, as a deductive science, on certain fundamental laws or general rules; and this has tended to increase its difficulty. In reality, the variety of algebra corresponds to the variety of phenomena. Neither mathematics itself, nor any branch or set of branches of mathematics, can be regarded as an isolated science. While, therefore, the logical development of algebraic reasoning must depend on certain fundamental relations, it is important that in the early study of the subject these relations should be introduced gradually, and not until there is some empirical acquaintance with the phenomena with which they are concerned.

8. The extension of the range of subjects to which mathematical methods can be applied, accompanied as it is by an extension of the range of study which is useful to the ordinary worker, has led in the latter part of the 19th century to an important reaction against the specialization mentioned in the preceding paragraph. This reaction has taken the form of a return to the alliance between algebra and geometry (\S 5), on which modern analytical geometry is based; the alliance, however, being concerned with the application of graphical methods to particular cases rather than to general expressions. These applications are sometimes treated under arithmetic, sometimes under algebra; but it is more convenient to regard graphics as a separate subject, closely allied to arithmetic, algebra, mensuration and analytical geometry.

9. The association of algebra with arithmetic on the one hand, and with geometry on the other, presents difficulties, in that geometrical measurement is based essentially on the idea of continuity, while arithmetical measurement is based essentially on the idea of discontinuity; both ideas being equally matters of intuition. The difficulty first arises in elementary mensuration, where it is partly met by associating arithmetical and geometrical measurement with the cardinal and the ordinal aspects of number respectively (see ARITHMETIC.) Later, the difficulty recurs in an acute form in reference to the continuous variation of a function. Reference to a geometrical interpretation seems at first sight to throw light on the meaning of a differential coefficient; but closer analysis reveals new difficulties, due to the geometrical interpretation itself. One of the most recent developments of algebra is the algebraic theory at number, which is devised with the view of removing these difficulties. The harmony between arithmetical and geometrical measurement, which was disturbed by the Greek geometers on the discovery of irrational numbers, is restored by an unlimited supply of the causes of disturbance.

10. Two other developments of algebra are of special importance. The theory of sequences and series is sometimes treated as a part of elementary algebra; but it is more convenient to regard the simpler cases as isolated examples, leading up to the general theory. The treatment of equations of the second and higher degrees introduces imaginary and complex numbers, the theory of which is a special subject.

11. One of the most difficult questions for the teacher of algebra is the stage at which, and the extent to which, the ideas of a negative number and of continuity may be introduced. On the one hand, the modern developments of algebra began with these ideas, and particularly with the idea of a negative number. On the other hand, the lateness of occurrence of any particular mathematical idea is usually closely correlated with its intrinsic difficulty. Moreover, the ideas which are usually formed on these points at an early stage are incomplete; and, if the incompleteness of an idea is not realized, operations in which it is implied are apt to be purely formal and mechanical. What are called negative numbers in arithmetic, for instance, are not really negative numbers but negative quantities (\S 27 (i.)); and the difficulties incident to the ideas of continuity have already been pointed out.

12. In the present article, therefore, the main portions of elementary algebra are treated in one section, without reference to these ideas, which are considered generally in two separate sections. These three sections may therefore be regarded as to a certain extent concurrent. They are preceded by two sections dealing with the introduction to algebra from the arithmetical and the graphical sides, and are followed by a section dealing briefly with the developments mentioned in \S \S 9 and 10 above.

[The intermediate portion of this article is typeset in TeX and is available elsewhere.]

C. HISTORY Various derivations of the word ``algebra,'' which is of Arabian origin, have been given by different writers. The first mention of the word is to be found in the title of a work by Mahommed ben Musa al-Khwarizmi (Hovarezmi), who flourished about the beginning of the 9th century. The full title is ilm al-jebr wa'l-muqabala, which contains the ideas of restitution and comparison, or opposition and comparison, or resolution and equation, jebr being derived from the verb jabara, to reunite, and muqabala, from gabala, to make equal. (The root jabara is also met with in the word algebrista, which means a ``bone-setter,'' and is still in common use in Spain.) The same derivation is given by Lucas Paciolus (Luca Pacioli), who reproduces the phrase in the transliterated form alghebra e almucabala, and ascribes the invention of the art to the Arabians.

Other writers have derived the word from the Arabic particle al (the definite article), and gerber, meaning ``man.'' Since, however, Geber happened to be the name of a celebrated Moorish philosopher who flourished in about the 11th or 12th century, it has been supposed that he was the founder of algebra, which has since perpetuated his name. The evidence of Peter Ramus (1515-1572) on this point is interesting, but he gives no authority for his singular statements. In the preface to his Arithmeticae libri duo et totidem Algebrae (1560) he says: ``The name Algebra is Syriac, signifying the art or doctrine of an excellent man. For Geber, in Syriac, is a name applied to men, and is sometimes a term of honour, as master or doctor among us. There was a certain learned mathematician who sent his algebra, written in the Syriac language, to Alexander the Great, and he named it almucabala, that is, the book of dark or mysterious things, which others would rather call the doctrine of algebra. To this day the same book is in great estimation among the learned in the oriental nations, and by the Indians, who cultivate this art, it is called aljabra and alboret; though the name of the author himself is not known.,' The uncertain authority of these statements, and the plausibility of the preceding explanation, have caused philologists to accept the derivation from al and jabara. Robert Recorde in his Whetstone of Witte (1557) uses the variant algeber, while John Dee (1527-1608) affirms that algiebar, and not algebra, is the correct form, and appeals to the authority of the Arabian Avicenna.

Although the term ``algebra'' is now in universal use, various other appellations were used by the Italian mathematicians during the Renaissance. Thus we find Paciolus calling it l'Arte Magiore; ditta dal vulgo la Regula de la Cosa over Alghebra e Almucabala. The name l'arte magiore, the greater art, is designed to distinguish it from l'arte minore, the lesser art, a term which he applied to the modern arithmetic. His second variant, la regula de la cosa, the rule of the thing or unknown quantity, appears to have been in common use in Italy, and the word cosa was preserved for several centuries in the forms coss or algebra, cossic or algebraic, cossist or algebraist, &c. Other Italian writers termed it the Regula rei et census, the rule of the thing and the product, or the root and the square. The principle underlying this expression is probably to be found in the fact that it measured the limits of their attainments in algebra, for they were unable to solve equations of a higher degree than the quadratic or square.

Franciscus Vieta (Francois Viete) named it Specious Arithmetic, on account of the species of the quantities involved, which he represented symbolically by the various letters of the alphabet. Sir Isaac Newton introduced the term Universal Arithmetic, since it is concerned with the doctrine of operations, not affected on numbers, but on general symbols.

Notwithstanding these and other idiosyncratic appellations, European mathematicians have adhered to the older name, by which the subject is now universally known.

It is difficult to assign the invention of any art or science definitely to any particular age or race. The few fragmentary records, which have come down to us from past civilizations, must not be regarded as representing the totality of their knowledge, and the omission of a science or art does not necessarily imply that the science or art was unknown. It was formerly the custom to assign the invention of algebra to the Greeks, but since the decipherment of the Rhind papyrus by Eisenlohr this view has changed, for in this work there are distinct signs of an algebraic analysis. The particular problem---a heap (hau) and its seventh makes 19---is solved as we should now solve a simple equation; but Ahmes varies his methods in other similar problems. This discovery carries the invention of algebra back to about 1700 B.C., if not earlier.

It is probable that the algebra of the Egyptians was of a most rudimentary nature, for otherwise we should expect to find traces of it in the works of the Greek aeometers. of whom Thales of Miletus (640-546 B.C.) was the first. Notwithstanding the prolixity of writers and the number of the writings, all attempts at extracting an algebraic analysis from their geometrical theorems and problems have been fruitless, and it is generally conceded that their analysis was geometrical and had little or no affinity to algebra. The first extant work which approaches to a treatise on algebra is by Diophantus (q.v.), an Alexandrian mathematician, who flourished about A.D. 350. The original, which consisted of a preface and thirteen books, is now lost, but we have a Latin translation of the first six books and a fragment of another on polygonal numbers by Xylander of Augsburg (1575), and Latin and Greek translations by Gaspar Bachet de Merizac (1621-1670). Other editions have been published, of which we may mention Pierre Fermat's (1670), T. L. Heath's (1885) and P. Tannery's (1893-1895). In the preface to this work, which is dedicated to one Dionysius, Diophantus explains his notation, naming the square, cube and fourth powers, dynamis, cubus, dynamodinimus, and so on, according to the sum in the indices. The unknown he terms arithmos, the number, and in solutions he marks it by the final s; he explains the generation of powers, the rules for multiplication and division of simple quantities, but he does not treat of the addition, subtraction, multiplication and division of compound quantities. He then proceeds to discuss various artifices for the simplification of equations, giving methods which are still in common use. In the body of the work he displays considerable ingenuity in reducing his problems to simple equations, which admit either of direct solution, or fall into the class known as indeterminate equations. This latter class he discussed so assiduously that they are often known as Diophantine problems, and the methods of resolving them as the Diophantine analysis (see EQUATION, Indeterminate.) It is difficult to believe that this work of Diophantus arose spontaneously in a period of general stagnation. It is more than likely that he was indebted to earlier writers, whom he omits to mention, and whose works are now lost; nevertheless, but for this work, we should be led to assume that algebra was almost, if not entirely, unknown to the Greeks.

The Romans, who succeeded the Greeks as the chief civilized power in Europe, failed to set store on their literary and scientific treasures; mathematics was all but neglected; and beyond a few improvements in arithmetical computations, there are no material advances to be recorded.

In the chronological development of our subject we have now to turn to the Orient. Investigation of the writings of Indian mathematicians has exhibited a fundamental distinction between the Greek and Indian mind, the former being pre-eminently geometrical and speculative, the latter arithmetical and mainly practical. We find that geometry was neglected except in so far as it was of service to astronomy; trigonometry was advanced, and algebra improved far beyond the attainments of Diophantus.

The earliest Indian mathematician of whom we have certain knowledge is Aryabhatta, who flourished about the beginning of the 6th century of our era. The fame of this astronomer and mathematician rests on his work, the Aryabhattiyam, the third chapter of which is devoted to mathematics. Ganessa, an eminent astronomer, mathematician and scholiast of Bhaskara, quotes this work and makes separate mention of the cuttaca (``pulveriser''), a device for effecting the solution of indeterminate equations. Henry Thomas Colebrooke, one of the earliest modern investigators of Hindu science, presumes that the treatise of Aryabhatta extended to determinate quadratic equations, indeterminate equations of the first degree, and probably of the second. An astronomical work, called the Surya-siddhanta (``knowledge of the Sun''), of uncertain authorship and probably belonging to the 4th or 5th century, was considered of great merit by the Hindus, who ranked it only second to the work of Brahmagupta, who flourished about a century later. It is of great interest to the historical student, for it exhibits the influence of Greek science upon Indian mathematics at a period prior to Aryabhatta. After an interval of about a century, during which mathematics attained its highest level, there flourished Brahmagupta (b. A.D. 598), whose work entitled Brahma-sphuta-siddhanta (``The revised system of Brahma'') contains several chapters devoted to mathematics. Of other Indian writers mention may be made of Cridhara, the author of a Ganita-sara (``Quintessence of Calculation''), and Padmanabha, the author of an algebra.

A period of mathematical stagnation then appears to have possessed the Indian mind for an interval of several centuries, for the works of the next author of any moment stand but little in advance of Brahmagupta. We refer to Bhaskara Acarya, whose work the Siddhanta-ciromani (``Diadem of anastronomical System''), written in 1150, contains two important chapters, the Lilavati (``the beautiful [science or art]'') and Viga-ganita (``root-extraction''), which are given up to arithmetic and algebra.

English translations of the mathematical chapters of the Brahma-siddhanta and Siddhanta-ciromani by H. T. Colebrooke (1817), and of the Surya-siddhanta by E. Burgess, with annotations by W. D. Whitney (1860), may be consulted for details.

The question as to whether the Greeks borrowed their algebra from the Hindus or vice versa has been the subject of much discussion. There is no doubt that there was a constant traffic between Greece and India, and it is more than probable that an exchange of produce would be accompanied by a transference of ideas. Moritz Cantor suspects the influence of Diophantine methods, more particularly in the Hindu solutions of indeterminate equations, where certain technical terms are, in all probability, of Greek origin. However this may be, it is certain that the Hindu algebraists were far in advance of Diophantus. The deficiencies of the Greek symbolism were partially remedied; subtraction was denoted by placing a dot over the subtrahend; multiplication, by placing bha (an abbreviation of bhavita, the ``product'') after the factom; division, by placing the divisor under the dividend; and square root, by inserting ka (an abbreviation of karana, irrational) before the quantity. The unknown was called yavattavat, and if there were several, the first took this appellation, and the others were designated by the names of colours; for instance, x was denoted by ya and y by ka (from kalaka, black).

A notable improvement on the ideas of Diophantus is to be found in the fact that the Hindus recognized the existence of two roots of a quadratic equation, but the negative roots were considered to be inadequate, since no interpretation could be found for them. It is also supposed that they anticipated discoveries of the solutions of higher equations. Great advances were made in the study of indeterminate equations, a branch of analysis in which Diophantus excelled. But whereas Diophantus aimed at obtaining a single solution, the Hindus strove for a general method by which any indeterminate problem could be resolved. In this they were completely successful, for they obtained general solutions for the equations ax(+ or -)by=c, xy=ax+by+c (since rediscovered by Leonhard Euler) and cy2=ax2+b. A particular case of the last equation, namely, y2=ax2+1, sorely taxed the resources of modern algebraists. It was proposed by Pierre de Fermat to Bernhard Frenicle de Bessy, and in 1657 to all mathematicians. John Wallis and Lord Brounker jointly obtained a tedious solution which was published in 1658, and afterwards in 1668 by John Pell in his Algebra. A solution was also given by Fermat in his Relation. Although Pell had nothing to do with the solution, posterity has termed the equation Pell's Equation, or Problem, when more rightly it should be the Hindu Problem, in recognition of the mathematical attainments of the Brahmans.

Hermann Hankel has pointed out the readiness with which the Hindus passed from number to magnitude and vice versa. Although this transition from the discontinuous to continuous is not truly scientific, yet it materially augmented the development of algebra, and Hankel affirms that if we define algebra as the application of arithmetical operations to both rational and irrational numbers or magnitudes, then the Brahmans are the real inventors of algebra.

The integration of the scattered tribes of Arabia in the 7th century by the stirring religious propaganda of Mahomet was accompanied by a meteoric rise in the intellectual powers of a hitherto obscure race. The Arabs became the custodians of Indian and Greek science, whilst Europe was rent by internal dissensions. Under the rule of the Abbasids, Bagdad became the centre of scientific thought; physicians and astronomers from India and Syria flocked to their court; Greek and Indian manuscripts were translated (a work commenced by the Caliph Mamun (813-833) and ably continued by his successors); and in about a century the Arabs were placed in possession of the vast stores of Greek and Indian learning. Euclid's Elements were first translated in the reign of Harun-al-Rashid (786-809), and revised by the order of Mamun. But these translations Were regarded as imperfect, and it remained for Tobit ben Korra (836-901) to produce a satisfactory edition. Ptolemy's Almagest, the works of Apollonius, Archimedes, Diophantus and portions of the Brahmasiddhanta, were also translated. The first notable Arabian mathematician was Mahommed ben Musa al-Khwarizmi, who flourished in the reign of Mamun. His treatise on algebra and arithmetic (the latter part of which is only extant in the form of a Latin translation, discovered in 1857) contains nothing that was unknown to the Greeks and Hindus; it exhibits methods allied to those of both races, with the Greek element predominating. The part devoted to algebra has the title al-jeur wa'lmuqabala, and the arithmetic begins with ``Spoken has Algoritmi,'' the name Khwarizmi or Hovarezmi having passed into the word Algoritmi, which has been further transformed into the more modern words algorism and algorithm, signifying a method of computing.

Tobit ben Korra (836-901), born at Harran in Mesopotamia, an accomplished linguist, mathematician and astronomer, rendered conspicuous Service by his translations of various Greek authors. His investigation of the properties of amicable numbers (q.v.) and of the problem of trisecting an angle, are of importance. The Arabians more closely resembled the Hindus than the Greeks in the choice of studies; their philosophers blended speculative dissertations with the more progressive study of medicine; their mathematicians neglected the subtleties of the conic sections and Diophantine analysis, and applied themselves more particularly to perfect the system of numerals (see NUMERAL), arithmetic and astronomy (q.v..) It thus came about that while some progress was made in algebra, the talents of the race were bestowed on astronomy and trigonometry (q.v..) Fahri des al Karbi, who flourished about the beginning of the 11th century, is the author of the most important Arabian work on algebra. He follows the methods of Diophantus; his work on indeterminate equations has no resemblance to the Indian methods, and contains nothing that cannot be gathered from Diophantus. He solved quadratic equations both geometrically and algebraically, and also equations of the form x2n+axn+b=0; he also proved certain relations between the sum of the first n natural numbers, and the sums of their squares and cubes.

Cubic equations were solved geometrically by determining the intersections of conic sections. Archimedes' problem of dividing a sphere by a plane into two segments having a prescribed ratio, was first expressed as a cubic equation by Al Mahani, and the first solution was given by Abu Gafar al Hazin. The determination of the side of a regular heptagon which can be inscribed or circumscribed to a given circle was reduced to a more complicated equation which was first successfully resolved by Abul Gud. The method of solving equations geometrically was considerably developed by Omar Khayyam of Khorassan, who flourished in the 11th century. This author questioned the possibility of solving cubics by pure algebra, and biquadratics by geometry. His first contention was not disproved until the 15th century, but his second was disposed of by Abul Weta (940-908), who succeeded in solving the forms x4=a and x4+ax3=b.

Although the foundations of the geometrical resolution of cubic equations are to be ascribed to the Greeks (for Eutocius assigns to Menaechmus two methods of solving the equation x3=a and x3=2a3), yet the subsequent development by the Arabs must be regarded as one of their most important achievements. The Greeks had succeeded in solving an isolated example; the Arabs accomplished the general solution of numerical equations.

Considerable attention has been directed to the different styles in which the Arabian authors have treated their subject. Moritz Cantor has suggested that at one time there existed two schools, one in sympathy With the Greeks, the other with the Hindus; and that, although the writings of the latter were first studied, they were rapidly discarded for the more perspicuous Grecian methods, so that, among the later Arabian writers, the Indian methods were practically forgotten and their mathematics became essentially Greek in character.

Turning to the Arabs in the West we find the same enlightened spirit; Cordova, the capital of the Moorish empire in Spain, was as much a centre of learning as Bagdad. The earliest known Spanish mathematician is Al Madshritti (d. 1007), whose fame rests on a dissertation on amicable numbers, and on the schools which were founded by his pupils at Cordoya, Dama and Granada. Gabir ben Allah of Sevilla, commonly called Geber, was a celebrated astronomer and apparently skilled in algebra, for it has been supposed that the word ``algebra', is compounded from his name.

When the Moorish empire began to wane the brilliant intellectual gifts which they had so abundantly nourished during three or four centuries became enfeebled, and after that period they failed to produce an author comparable with those of the 7th to the 11th centuries.

In Europe the decline of Rome was succeeded by a period, lasting several centuries, during which the sciences and arts were all but neglected. Political and ecclesiastical dissensions occupied the greatest intellects, and the only progress to be mcorded is in the art of computing or arithmetic, and the translation of Arabic manuscripts. The first successful attempt to revive the study of algebra in Christendom was due to Leonardo of Pisa. an Italian merchant trading in the Mediterranean. His travels and mercantile experience had led him to conclude that the Hindu methods of computing, were in advance of those then in general use, and in 1202 he published his Liber Abaci, which treats of both algebra and arithmetic. In this work, which is of great historical interest, since it was published about two centuries before the art of printing was discovered, he adopts the Arabic notation for nulnbers, and solves many problems, both arithmetical and algebraical. But it contains little that is original, and although the work created a great sensation when it was first published, the effect soon passed away, and the book was practically forgotten. Mathematics was more or less ousted from the academic curricula by the philosophical inquiries of the schoolmen, and it was only after an interval of nearly three centuries that a worthy successor to Leonardo appeared. This was Lucas Paciolus (Lucas de Burgo), a Minorite friar, who, having previously written works on algebra, arithmetic and geometry, published, in 1494, his principal work, entitled Summa de Arithmetica, Giometria, Proportioni et Proportionalita. In it he mentions many earlier writers from whom he had learnt the science, and although it contains very little that cannot be found in Leonardo's work, yet it is especially noteworthy for the systematic employment of symbols, and the manner in which it reflects the state of mathematics in Europe during this period. These works are the earliest printed books on mathematics. The renaissance of mathematics was thus effected in Italy, and it is to that country that the leading developments of the following century were due. The first difficulty to be overcome was the algebraical solution of cubic equations, the pons asinorum of the earlier mathematicians. The first step in this direction was made by Scipio Ferro (d. 1526), who solved the equation x3+ax=b. Of his discovery we know nothing except that he declared it to his pupil Antonio Marie Floridas. An imperfect solution of the equation x3+px2=q was discovered by Nicholas Tartalea (Tartaglia) in 1530, and his pride in this achievement led him into conflict with Floridas, who proclaimed his own knowledge of the form resolved by Ferro. Mutual recriminations led to a public discussion in 1535, when Tartalea completely vindicated the general applicability of his methods and exhibited the inefficiencies of that of Floridas. This contest over, Tartalea redoubled his attempts to generalize his methods, and by 1541 he possessed the means for solving any form of cubic equation. His discoveries had made him famous all over Italy, and he was earnestly solicited to publish his methods; but he abstained from doing so, saying that he intended to embody them in a treatise on algebra which he was preparing. At last he succumbed to the repeated requests of Girolamo or Geronimo Cardano, who swore that he would regard them as an inviolable secret. Cardan or Cardano, who was at that time writing his great work, the Ars Magna, could not restrain the temptation of crowning his treatise with such important discoveries, and in 1545 he broke his oath and gave to the world Tartalea's rules for solving cubic equations. Tartalea, thus robbed of his most cherished possession, was in despair. Recriminations ensued until his death in 1557, and although he sustained his claim for priority, posterity has not conceded to him the honour of his discovery, for his solution is now known as Cardan's Rule.

Cubic equations having been solved, biquadratics soon followed suit. As early as 1539 Cardan had solved certain particular cases, but it remained for his pupil, Lewis (Ludovici) Ferrari, to devise a general method. His solution, which is sometimes erroneously ascribed to Rafael Bombelh, was published in the Ars Magna. In this work, which is one of the most valuable contributions to the literature of algebra, Cardan shows that he was familiar with both real positive and negative roots of equations whelher rational or irrational, but of imaginary roots he was quite ignorant, and he admits his inability to resolve the so-called ``irreducible case'' (see EQUATION.) Fundamental theorems in the theory of equations are to be found in the same work. Clearer ideas of imaginary quantities and the ``irreducible case'' were subsequently published by Bombelli, in a work of which the dedication is dated 1572, though the book was not published until 1579.

Contemporaneously with the remarkable discoveries of the Italian mathematicians, algebra was increasing in popularity in Germany, France and England. Michael Stifel and Johann Scheubelius (Scheybl) (1494-1570) flourished in Germany, and although unacquainted with the work of Cardan and Tartalea, their writings are noteworthy for their perspicuity and the introduction of a more complete symbolism for quantities and operations. Stifel introduced the sign (+) for addition or a positive quantity, which was previously denoted by plus, piu, or the letter p. Subtraction, previously written as minus, mone or the letter m, was symbolized by the sign (-) which is still in use. The square root he denoted by (sqrt. ), whereas Paciolus, Cardan and others used the letter R.

The first treatise on algebra written in English was by Robert Recorde, who published his arithmetic in 1552, and his algebra entitled The Whetstone of Witte, which is the second part of Arithmetik, in 1557. This work, which is written in the form of a dialogue, closely resembles the works of Stifel and Scheubelius, the latter of whom he often quotes. It includes the properties of numbers; extraction of roots of arithmetical and algebraical quantities, solutions of simple and quadratic equations, and a fairly complete account of surds. He introduced the sign (=) for equality, and the terms binomial and residual. Of other writers who published works about the end of the 16th century, we may mention Jacques Peletier, or Jacobus Peletarius (De occulta parto Numerorum, quare Algebram vocant, 1558); Petrus Ramus (Arithmeticae Libri duo et totidem Algebrae, 1560), and Christoph Clavius, who wrote on algebra in 1580, though it was not published until 1608. At this time also flourished Simon Stevinus (Stevin) of Bruges, who published an arithmetic in 1585 and an algebra shortly afterwards. These works possess considerable originality, and contain many new improvements in algebraic notation; the unknown (res) is denoted by a small circle, in which he places an integer corresponding to the power. He introduced the terms multinomial, trinomial, quadrinomial, &c., and considerably simplified the notation for decimals.

About the beginning of the 17th century various mathematical works by Franciscus Vieta were published, which were afterwards collected by Franz van Schooten and republished in 1646 at Leiden. These works exhibit great originality and mark an important epoch in the history of algebra. Vieta, who does not avail himself of the discoveries of his predecessors--the negative roots of Cardan, the revised notation of Stifel and Stevin, &c.--introduced or popularized many new terms and symbols, some of which are still in use. He denotes quantities by the letters of the alphabet, retaining the vowels for the unknown and the consonants for the knowns; he introduced the vinculum and among others the terms coefficient, affirmative, negative, pure and adjected equations. He improved the methods for solving equations, and devised geometrical constructions with the aid of the conic sections. His method for determining approximate values of the roots of equations is far in advance of the Hindu method as applied by Cardan, and is identical in principle with the methods of Sir Isaac Newton and W. G. Horner.

We have next to consider the works of Albert Girard, a Flemish mathematician. This writer, after having published an edition of Stevin's works in 1625, published in 1629 at Amsterdam a small tract on algebra which shows a considerable advance on the work of Vieta. Girard is inconsistent in his notation, sometimes following Vieta, sometimes Stevin; he introduced the new symbols ff. for greater than and sec. for less than; he follows Vieta in using the plus (+) for addition, he denotes subtraction by Recorde's symbol for equality (=), and he had no sign for equality but wrote the word out. He possessed clear ideas of indices and the generation of powers, of the negative roots of equations and their geometrical interpretation, and was the first to use the term imaginary roots. He also discovered how to sum the powers of the roots of an equation.

Passing over the invention of logarithms (q.v.) by John Napier, and their development by Henry Briggs and others, the next author of moment was an Englishman, Thomas Harriot, whose algebra (Artis analyticae praxis) was published posthumously by Walter Warner in 1631. Its great merit consists in the complete notation and symbolism, which avoided the cumbersome expressions of the earlier algebraists, and reduced the art to a form closely resembling that of to-day. He follows Vieta in assigning the vowels to the unknown quantities and the consonants to the knowns, but instead of using capitals, as with Vieta, he employed the small letters; equality he denoted by Recorde's symbol, and he introduced the signs > and < for greater than and less than. His principal discovery is concerned with equations, which he showed to be derived from the continued multiplication of as many simple factors as the highest power of the unknown, and he was thus enabled to deduce relations between the coefficients and various functions of the roots. Mention may also be made of his chapter on inequalities, in which he proves that the arithmetic mean is always greater than the geometric mean.

William Oughtred, a contemporary of Harriot, published an algebra, Clavis mathematicae, simultaneously with Harriot's treatise. His notation is based on that of Vieta, but he introduced the sign X for multiplication, @ for continued proportion, :: for proportion, and denoted ratio by one dot. This last character has since been entirely restricted to multiplication, and ratio is now denoted by two dots (:). His symbols for greater than and less than (@ and @) have been completely superseded by Harriot's signs`

So far the development of algebra and geometry had been mutually independent, except for a few isolated applications of geometrical constructions to the solution of algebraical problems. Certain minds had long suspected the advairages which would accrue from the unrestricted application of algebra to geometry, but it was not until the advent of the philosopher Rene Descartes that the co-ordination was effected. In his famous Geometria (1637), which is really a treatise on the algebraic representation of geometric theorems, he founded the modern theory of analytical geometry (see GEOMETRY), and at the same time he rendered signal service to algebra, more especially in the theory of equations. His notation is based primarily on that of Harriot; but he differs from that writer in retaining the first letters of the alphabet for the known quantities and the final letters for the unknowns.

The 17th century is a famous epoch in the progress of science, and the mathematics in no way lagged behind. The discoveries of Johann Kepler and Bonaventura Cavalieri were the foundation upon which Sir Isaac Newton and Gottfried Wilhelm Leibnitz erected that wonderful edifice, the Infinitesimal Calculus (q.v..) Many new fields were opened up, but there was still continual progress in pure algebra. Continued fractions, one of the earliest examples of which is Lord Brouncker's expression for the ratio of the circumference to the diameter of a circle (see CIRCLE), were elaborately discussed by John Wallis and Leonhard Euler; the convergency of series treated by Newton, Euler and the Bernoullis; the binomial theorem, due originally to Newton and subsequently expanded by Euler and others, was used by Joseph Louis Lagrange as the basis of his Calcul des Fonctions. Diophantine problems were revived by Gaspar Bachet, Pierre Fermat and Euler; the modern theory of numbers was founded by Fermat and developed by Euler, Lagrange and others; and the theory of probability was attacked by Blaise Pascal and Fermat, their work being subsequently expanded by James Bernoulli, Abraham de Moivre, Pierre Simon Laplace and others. The germs of the theory of determinants are to be found in the works of Leibnitz; Etienne Bezout utilized them in 1764 for expressing the result obtained by the process of elimination known by his name, and since restated by Arthur Cayley.

In recent times many mathematicians have formulated other kinds of algebras, in which the operators do not obey the laws of ordinary algebra. This study was inaugurated by George Peacock, who was one of the earliest mathematicians to recognize the symbolic character of the fundamental principles of algebra. About the same time, D. F. Gregory published a paper ``on the real nature of symbolical algebra.'' In Germany the work of Martin Ohm (System der Mathematik, 1822) marks a step forward. Notable service was also rendered by Augustus de Morgan, who applied logical analysis to the laws of mathematics.

The geometrical interpretation of imaginary quantities had a far-reaching influence on the development of symbolic algebras. The attempts to elucidate this question by H. Kuhn (1750-1751) and Jean Robert Argand (1806) were completed by Karl Friedrich Gauss, and the formulation of various systems of vector analysis by Sir William Rowan Hamilton, Hermann Grassmann and others, followed. These algebras were essentially geometrical, and it remained, more or less, for the American mathematician Benjamin Peirce to devise systems of pure symbolic algebras; in this work he was ably seconded by his son Charles S. Peirce. In England, multiple algebra was developed by James Joseph Sylvester, who, in company with Arthur Cayley, expanded the theory of matrices, the germs of which are to be found in the writings of Hamilton (see above, under (B); and QUATERNIONS.)

The preceding summary shows the specialized nature which algebra has assumed since the 17th century. To attempt a history of the development of the various topics in this article is inappropriate, and we refer the reader to the separate articles.

REFERENCES.---The history of algebra is treated in all historical works on mathematics in general (see MATHEMATICS: References.) Greek algebra can be specially studied in T. L. Heath's Diophantus. See also John Wallis, Opera Mathematica (1693-1699), and Charles Sutton, Mathematical and Philosophical Dictionary (1815), article ``Algebra.'' (C. E.*)

[The article on Algebraic Forms is typeset in TeX and is available elsewhere.]

ALGECIRAS, or ALGEZIRAS, a seaport of southern Spain in the province of Cadiz, 6 m. W. of Gibraltar, on the opposite side of the Bay of Algeciras. Pop. (1900) 13,302. Algeciras stands at the head of a railway from Granada, but its only means of access to Gibraltar is by water. Its name, which signifies in Arabic the island, is derived from a small islet on one side of the harbour. It is supplied with water by means of a beautiful aqueduct. The fine winter climate of Algeciras attracts many invalid visitors, on whom the town largely depends for its prosperity. The harbour is bad, but at the beginning of the 20th century it became important as a fishing-station. Whiting, soles, bream, bass and other fish are caught in great quantities by the Algeciras steam-trawlers, which visit the Moroccan coast, as well as Spanish and neutral waters. There is also some trade in farm produce and building materials which supplies a fleet of small coasters with cargo.

Algeciras was perhaps the Portus Albus of the Romans, but it was probably refounded in 713 by the Moors, who retained possession of it until 1344. It was then taken by Alphonso XI. of Castile after a celebrated siege of twenty months, which attracted Crusaders from all parts of Europe; among them being the English earl of Derby, grandson of Edward III. It is said that during this siege gunpowder was first used by the Moors in the wars of Europe. The Moorish city was destroyed by Alphonso; it was first reoccupied by Spanish colonists from Gibraltar in 1704; and the modern town was erected in 1760 by King Charles III. During the siege of Gibraltar in 1780- 1782, Algeciras was the station of the Spanish fleet and floating batteries. On the 6th of July 1801 the English admiral Sir James Saumarez attacked a Franco-Spanish fleet off Algeciras, and sustained a reverse; but on the 12th he again attacked the enemy, whose fleet was double his own strength, and inflicted on them a complete defeat. The important international conference on Moroccan affairs, which resulted in an agreement between France and Germany, was held at Algeciras from the 16th of January to the 7th of April 1906. (See MOROCCO.)

ALGER OF LIEGE (d c. 1131), known also as ALGER OF CLUNY and ALGERUS MAGISTER, a learned French priest who lived in the first half of the 12th century. He was first a deacon of the church of St Bartholomew at Liege, his native town, and was then appointed (c. 1100) to the cathedral church of St Lambert. He declined many offers from German bishops and finally retired to the monastery of Cluny, where he died about 1131 at a great age and leaving a good reputation for piety and intelligence. His History of the Church of Liege, and many of his other works, are lost. The most important of those still extant are: 1. De Misericordia et Justitia, a collection of biblical and patristic extracts with a commentary (an important work for the history of church law and discipline), which is to be found in the Anecdota of Martene, vol. v. 2. De Sacramentis Corporis et Sanguinis Domini; a treatise, in three books, against the Berengarian heresy, highly commended by Peter of Cluny and Erasmus. 3. De Gratia et Libero Arbitrio; given in B. Pez's Anecdota, vol. iv. 4. De Sacrificio Missae; given in the Collectio Scriptor. Vet. of Angelo Mai, vol. ix. p. 371.

See Migne, Patrol Ser. Lat. vol. clxxx. pp. 739-.972; Herzog- Hauck, Realencyk.fur prot. Theol., art. by S. M. Deutsch.

ALGER, RUSSELL ALEXANDER (1836--1907), American soldier and politician, was born in Lafayette township, Medina county, Ohio, on the 27th of February 1836. Left an orphan at an early age, he worked on a farm to pay his expenses at Richfield (Ohio) Academy, was a schoolmaster for two winters, and, having studied law in the meantime, was admitted to the bar in 1859. He began practice at Cleveland, Ohio, but early in 1860 he removed to Michigan, where he abandoned his profession and engaged in the lumber business. Enlisting in a Michigan cavalry regiment in September 1861, he rose from captain to colonel, distinguished himself in the Gettysburg campaign and under Sheridan in the Shenandoah Valley, and in 1864 and 1865 respectively received the brevets of brigadier-general and major-general of volunteers. After the war he invested extensively in pine lands in Michigan, and accumulated a large fortune in the lumber business. In 1884 he was elected governor of Michigan on the Republican ticket, serving from 1885 to 1887. In 1889--1890 he was commander-in-chief of the Grand Army of the Republic. From 1897 to 1899 he was secretary of war in President McKinley's cabinet. His administration of the war department during the Spanish-American War was severely criticized for extravagance in army contracts, for unpreparedness, and for genetal inefficiency, charges which he answered in his The Spanish-American War (1901). The extent of his personal responsibility is at least uncertain. In 1902 he was appointed by the governor of Michigan, and in 1903 was elected by the state legislature, as United States senator to complete the unexpired term of James Mcmillan (1838-1902). He died at Washington, D.C., on the 24th of January 1907.

ALGERIA (Algerie), a country of North Africa belonging to France, bounded N. by the Mediterranean, W. by Morocco, S. by the Sahara and E. by Tunisia. The boundaries, however, are in part not accurately determined. Algeria extends for about 650 m. along the coast, and stretches inland from 320 to 380 m., lying between 2 deg. 10' W. and 8 deg. 50, E., and 32 deg. and 37 deg. N. It is divided, politically, into three departments-- Oran in the west, Algiers in the centre and Constantine in the east. Its area is 184,474 sq. m., exclusive of the dependent Saharan regions, which have an area of some 750,000 sq. m. (see SAHARA, TUAT, &c.).

Physical Features.--The character of the Algerian coast is severe and inhospitable. The western half is bordered by a hilly rampart, broken only here and there, in the bays where the larger streams find their outlet, by flat and sandy plains. Between Dellys and Philippeville high mountains rise almost sheer from the sea, leaving only a narrow strip of beach. East of Philippeville the mountains recede from the coast, and the rampart of hills reappears. Only between Bona and La Calle is the general character of the sea-board low and sandy. Save near the towns and in the cultivated district of Kabylia, the coast is bare and uninhabited; and in spite of numerous indentations, of which the most important going from west to east are the Gulf of Oran, the Gulf of Arzeu, the Bay of Algiers, and the gulfs of Bougie, Stora and Bona, there are few good harbours. From time immemorial, indeed, this coast has had an evil reputation among mariners, quite apart from the pirates who for centuries made it the base of their depredations. A violent current, starting from the Straits of Gibraltar, rushes eastward along the shore, and, hurled back from the headlands, is deflected to the West. In summer the east wind brings dense and sudden fogs; while in winter the northerly gales blow straight into the mouths of the harbours. In these circumstances navigation is especially perilous for sailing craft. The terrors of this ``savage sea and inhospitable shore,'' once described by Sallust, have, however, been greatly mitigated by the introduction of steam, the improvement of the harbours, and the establishment by the French government of an excellent system of lighthouses.

Southward from the sea the country falls naturally into three divisions, clearly distinguished by their broad physical characteristics. The healthy, and on the whole fertile coast region, from 50 to 100 m. in width, is known, as in Morocco and Tunisia. as the Tell (Arabic for ``hill''). It is a mountainous country intersected with rocky canons and fertile valleys, which occasionally broaden out into alluvial plains like that of the Shelif, or the Metija near Algiers, or those in the neighbourhood of Oran and Bona. Behind the Tell is a lofty table-land with an average elevation of 3000 ft., consisting of vast plains, for the most part arid or covered with esparto grass, in the depressions of which are great salt lakes and swamps (Arabic, shats) fed by streams which can find no outlet to the sea through the encircling hills. To the south this region is divided by the Great Atlas from the deserts of the Sahara, with its oases, in which the boundary of Algeria is lost.

The country is traversed by lofty ranges of the Atlas system, which run nearly parallel to the coast, and rise in places over 7000 ft. These are commonly divided into two leading chains, distinguished as the Great1 and Little Atlas. The Great, or Saharan Atlas contains some of the highest points in the country. The chief ranges are Ksur and Amur in the west and the Aures in the east. The peak of Shellia, the highest point in Algeria, in the Aures range, has a height of 7611 ft. In the Amur are Jebel Ksel (6594 ft.) and Tuila Makna (6561 ft.). The Little Atlas, otherwise the Tell or Maritime Atlas, lies between the sea and the Saharan Atlas, and is composed of many distinct ranges, generally of no great elevation and connected by numerous transverse chains forming extensive table-lands and elevated valleys. The principal ranges of the Little Atlas--from west to east--are the Tlemcen (5500 ft.); the Warsenis (with Kef Sidi Omar, 6500 ft.); the Titeri (4900 ft.); the Jurjura, with the peak of Lalla Kedija (7542 ft.) and Mount Babor (6447 ft.); and the Mejerda (3700 ft.), which extends into Tunisia. The Jurjura range, forming the background of the plains between Algiers and Bougie, extends through the district of Kabylia, with which for grandeur of scenery no other part of Algeria can compare. South of the Jurjura and separated from it by the valley of the Sahel, is the Biban range with a famous double pass of the same name, through which alone access is gained to the highlands beyond. The Bibans or Portes de fer (Iron Gates) consist of two defiles with stupendous walls of rock, which by erosion have assumed the most fantastic shapes. In the case of the Petite porte the walls in some places are not more than twelve feet apart. The Dahra range (see MOSTAGANEM) overlooks the sea, and is separated from the Warsenis by the valley of the Shelif (see ATLAS MOUNTAINS, SAHARA and TUAT.)

The rivers are numerous but the majority are short. Most of them rise in the mountains near the coast, and rush down through deep and rocky channels. During the rainy season they render communication between different parts of the country extremely difficult. The most important river, both from its length and volume, is the Shelif. It rises on the northern slopes of the Amur mountains and flows N.E. across the high plateau, piercing the little Atlas between the Warsenis and Titeri ranges. It then turns W. and reaches the Mediterranean at the eastern end of the Gulf of Arzeu. The Shelif, which has many tributaries, is about 430 m. long. The Seybuse (about 150 m. long), formed by the union of several small streams in the department of Constantine, runs through a fertile valley and reaches the Mediterranean near Bona. The Sahel (about 100 m. long), which contains the greatest body of water after the Shelif, rises in the department of Algiers near Aumale, and flows for the most part N.E. to its mouth near Bougie. The Kebir or Rummel--the river is known by both names--is formed by the union of several small streams south of Constantine, and flows past that town N.W. 140 m. to the sea. Among the less important rivers which empty into the Mediterranean are the Macta, the Tafna, the Harrach and the Mazafran. The Macta, but 3 m. long, enters the sea in the Gulf of Arzeu, some 25 m. W. of the mouth of the Shelif. It is formed by the Habra (140 m.) and the Sig (130 m.), which rise in the Amur mountains and flowing north unite in a marshy plain, whence issues the Macta. On the lower courses of the Habra and the Sig, barrages have been built for irrigation purposes. The Habra barrage holds 38,000,000 cubic metres; that on the Sig 18,000,000. The Tafna (about 100 m.) rises in a large cavern in the mountains south of Tlemcen and flows N.E. to the sea at Rachgun. It has many affluents; the largest, the Isser (70 m.), joins it on the east bank about 30 m. above its mouth. The Harrach (40 m.), a picturesque stream, enters the Mediterranean in the Bay of Algiers. The Mazafran (50 m.) crosses the plains S.W of Algiers, reaching the sea N. of Kolea. The Mejerda and its affluent the Mellegue, rivers of Tunisia (q.v.), have their rise in Algeria, in the mountainous country east of Constantine. None of these rivers is navigable. Besides these there are a number of streams in the interior, but they are usually dry except in the rainy season.

Algeria abounds in extensive salt lakes and marshes. Of the lakes in the northern part of the country near the coast the principal are,--the Fezara, 14 m. S.W. of Bona; Sebkha and El Melah, south of Oran; and three small lakes in the immediate vicinity of La Calle. In the high plateaus are the Shat-el-Gharbi or Western Shat, the Shat-el-Shergui or Eastern Shat, the Zarhez- Gharbi and the Zarhez-Shergui, the Shat-el-Hodna and a number of others. South of the Jebel Aures is another series of salt lakes closely connected with the Shat-el-Jerid (of Tunisia). The chief of these is the Shat Melrir. There are a number of warm mineral springs, containing principally salts of lime, used with success by both Arabs and Europeans in several kinds of disease.

One of the most remarkable groups of springs is near Guelma, in the department of Constantine. There are two principal sources. Their waters unite in one stream whose course is marked by gigantic limestone cones, some of which are 36 ft. high. The water, which is at boiling point, falls into natural basins of a creamy white colour, formed by the deposit of carbonate of lime. The springs are known to the Arabs as Hammam Meskutin (the ``accursed baths''). The name and the cones are accounted for by a legend which represents that at this spot lived a sheikh who, finding his sister too beautiful to be married to anyone else, determined to espouse her himself. Whilst the marriage festivities were being celebrated the judgment of Heaven descended on the guilty pair; fire came from below; the water became hot and the sheikh and his sister were turned into stone. Within a mile of Hammam Meskutin are ferruginous and sulphureous springs.

[Geology.--The geology of Algeria has been worked out in considerable detail by French geologists. Rocks of Archean and Palaeozoic ages contribute only a small share, but there is a very complete sequence of formations from the Lias to those of recent date. An interesting and orderly petrological sequence of Tertiary igneous rocks has been determined.

Archean rocks form the cores of the ancient crystalline masses within the littoral zone from Algiers to Bona. They consist of gneiss, mica-schist, quartzites, crystalline limestones and conglomerates. Primary deposits are doubtfully represented by the detached fragments of unfossiliferous strata of Traras, Blida and east of Orleansville. Carboniferous and Permian strata are possibly represented by some black and grey micaceous shales with beds of coal in the Jurjura. At Jebel-kahar and west of Traras, Pomel attributes certain conglomerates, red sandstones and purple and green shales to the Permian. The rocks of Secondary and Tertiary ages have been profoundly affected by the Alpine movements, and are thrown into a series of complex folds, so that in numerous instances their stratigraphy is imperfectly understood. The gypsiferous and saliferous marls of Shellata, Suk Ahras and Ain Nussi have yielded Triassic fossils. Triassic rocks are considered to be present in Constantine and in the Jurjura. Rhaetic beds (Infra Lias), consisting of dolomites and siliceous limestones, have been recognized at Saida. The lower and middle divisions of the Jurassic, composed of massive limestones more or less siliceous and overlain by the marls and highly fossiliferous limestones of the Upper Lias, play an important part in the constitution of the chief mountains of the Tell. In south Oran they determine the principal axes of the mountain ranges. The Inferior Cretaceous rocks include the Neocomian and Gault (Albian and Aptian) subdivisions, and form the flanks of the mountains in the Tell. In the south the Albian subdivision of the Gault is alone represented. Rocks of Upper Cretaceous age are represented in all their stages. The Cenomanian presents two distinct facies. North of the Atlas it belongs to the European type, in the south it contains a fauna of oysters and sea-urchins belonging to the facies ``africano-syrian'' of Zittel. There is a continuous transition between the Senonian and Danian, proving that the Algerian region did not participate in the immersion which occurred in Provence and in the Corbieres of southern France during the Danian epoch. The Lower Eocene rocks contain the chief phosphatic deposits of Algeria, those of the Tebessa region being the best known. Certain species of nummulites, which are very common, distinguish the various subdivisions of the Eocene. The highest beds, consisting of quartzites, shales, marls and sandstones with the remains of fucoids, are found in the Jurjura and Shellata. The Oligocene period consists of a marine phase confined to the littoral zone of Kahylia, and of a continental phase occupying vast areas composed of lacustrine, alluvial, gypsiferous marls, sandstones and conglomerates. The Miocene formation obtains its greatest development in Oran and is much expanded in the Tell. At the close of the Lower Miocene period (beds with Ostrea crassissima) great modifications in the relief and limits of the Algerian formations took place. Hitherto marine conditions were confined to the littoral; in Middle Miocene times (Helvetian) the sea broke in and spread in a south-east direction in the form of long ramified fjords but did not extend as far as the Sahara. To the Pliocene period the marine deposits of the Sahel of Algiers and of the Sahel Jijelli must be attributed; also the lacustrine marls and limestone of the basin of Constantine, and the ancient alluviums of the basins and depressions which bear no relation to the existing valleys. Among the Tertiary volcanic rocks those of acid types (granites, granulites) were the first to appear and are developed latitudinally; rocks of intermediate type (dacites, andesites) characterize the Miocene and early Pliocene periods; while the basic rocks (ophites, elaeolite syenites and basalts) attained their maximum in later Pliocene and Quaternary times. Their development, feeble as compared with the acid rocks, is meridional. The Quaternary period includes an older stage containing fragments of fossils from the underlying formations; a later stage containing the bones of Hippopotamus, Elephas, Rhinoceros, Camelus, Equus; and finally the vast accumulations of sand which began to be formed in prehistoric times. The broad platforms of the hamada are covered with Quaternary deposits. (W. G.*)]

CIimate.--Although Algeria enjoys a warm climate, the temperature varies considerably in different parts, according to the elevation and configuration of the country. Along the coast the weather is very mild, the thermometer rarely falling to freezing-point even in winter. The coldest month is January, the hottest August. The mean annual temperature in the coast plains is 66 deg. F. Heavy rains prevail from December to March, and rain is not uncommon during other months also, excepting June, July, August and September, which are very hot and rainless. The average annual fall is 29 in. On the mountains and the high plateaus the winter is often very severe; snow lies for six months on the higher peaks of the Kabyle mountains. On the plateaus the temperature passes from one extreme to the other, and rain seldom falls. (For the climate of the Saharan region see SAHARA.) Throughout Algeria, especially in the summer, there is a great difference between day and night temperature, notably in the inland districts. Between May and September the sirocco, or hot wind of the desert, sweeps at intervals over the country, impregnating the air with fine sand; but in general, with the exception of the vicinity of the marshes, the climate is healthy. Its salubrity has been increased by the draining of many marshes in the neighbourhood of the larger towns.

Fauna and Flora.--The fauna of Algeria resembles that of the Mediterranean system generally, though many animals once common to South Europe and North Africa--such as the lion, panther, hyena and jackal--are now extinct in Europe. Lions, formerly plentiful, have disappeared, and leopards and panthers are rare; but jackals, hyenas and Algerian apes are not uncommon. Wild boars are found in the oak forests, and brown bears in the uplands. In the south are various species of antelope and wild goat. Red deer (Cervus elaphus barbarus), which differ from the typical European species only in the fact that the second tine is absent from their antlers, a peculiarity which they share with the red deer of Spain and Corsica, are still found in the forest of Beni Saleh in the department of Constantine, but are being exterminated by forest fires and poaching Arabs. Of domestic animals the camel and sheep are the most important. The chief wealth of the Arab tribes of the plateaus consists in their immense flocks of sheep. The horses and mules of Algeria are noted; and the native cattle are an excellent stock on which to graft the better European varieties. Of birds, eagles, vultures, hawks, owls and quails are common; snipe, curlews, plovers, storks and herons frequent the marshy parts; and the ostrich the desert. Partridges and woodcocks are fairly common. Among the reptiles are various species of serpents, tortoises, turtles, lizards, &c. Locusts are common and sometimes do great damage. Scorpions are numerous in the acid regions. Algerian prawns, especially those of Bona, are large and of a delicate flavour. Of the twenty-one species of freshwater fish, five are peculiar to the country, but none is of much economic value save the barbel and eel. A species of trout is found in the streams near Collo, but in none of the other rivers.

The flora of Algeria consists of about 3000 species, of which some 450 are indigenous to the country, 100 being peculiar to the Sahara. The flora of the Tell is South European in character. The agave and prickly pear, the myrtle, the olive and the dwarf palm grow luxuriantly; and the fields are covered with narcissus, iris and other flowers of every hue. Roses, geraniums, and the like, bloom throughout the winter. The flora of the high plateaus consists chiefly of grasses, notably various kinds of alfa or esparto, and aromatic herbs. In the Saharan oases the characteristic tree is the date palm--``the king of the desert.'' Over 11,000 sq. m. of the mountainous country near the coast are covered with forests of various species of oak, pine, fir, cedar, elm, ash, maple, olive, many of them of gigantic size, and other trees; and on the slopes of the mountains up to 3800 ft. above the sea the fig is common. Its fruit forms one of the staple articles of food among the Kabyles. Cork and carob trees are also very common. A magnificent conifer, the Atlantic pinsapo (Abies Pinsapo), is found on the heights round Bougie. The forests suffer great damage from fires, occasioned in part by the custom of burning up the grass every autumn, and in part by incendiarism. In 1902 alone, according to the British consular report, ``at a moderate estimate the number of trees damaged or destroyed might be put down at 6,000,000.'' Forestry is a state-protected industry, the government owning over 500,000 acres of forest. The chief tree which has commercial value is the cork, and the stripping of the bark is under official supervision. The first cork harvest was gathered in 1890, when 1474 cwt. were sold for L. 1361. Since that date the yield has been very great. Another tree of great commercial value is the soap tree (Sapindus utilis), introduced into the country in 1845 and grown extensively in low-lying lands near the coast.

Inhabitants.--Algeria had in 1906 a population of 5,231,850, consisting of a medley of European, Eastern and African races. The census showed that in addition to French settlers and their descendants (278,976) there were 117,475 Spaniards (most of whom are found in the department of Oran), 33,153 Italians (chiefly in the department of Constantine), 64,645 Jews, 6217 Maltese, and smaller communities of British, Germans, Levantines and Greeks. There were, moreover, 170,444 naturalized French citizens, mainly of Spanish and Italian origin. (These figures are exclusive of 73,790 persons counted apart, as not enjoying municipal rights. In the 73,799 the troops, French and native, are included). The total European population, in which category are reckoned the Jews, other than those of Mzab, was 680,263. Compared with the census of 1901 the figures of 1906 showed a decrease of 14,000 French, 36,000 Spaniards and 5000 Italians, but an increase of nearly 100,000 in the foreigners naturalized. Of other races: (1) The Berbers (q.v.) constitute 75% of the entire population. The Kabyles (q.v.), a division of the Berbers, occupy chiefly the more mountainous parts of the Tell, but some live in the plains and valleys. (2) Arabs, a numerous class, are found principally in the south. (3) The so-called ``Moors,'' generally of mixed blood, inhabit the towns and villages near the sea-coast. (4) Negroes, originally brought from the interior and sold as slaves, are now found chiefly in the towns, where they serve as labourers and domestic servants. (5) Mzabites (q.v.) or Beni-Mzab, a distinct branch of the Berber race, are for the most part engaged in petty trade, and are distinguished by their sleeveless coats of many colours. (6) A few Tuareg (q.v.), another division of the Berbers, are among the nomads found in the Algerian Sahara. The Kabyles, Mzabites, Tuareg, Arabs and Moors all profess Mahommedanism, though it is only among the Arabs that its tenets are held in any purity. The census of 1906 gave the number of the native population at 4,447,149. There were also 28,639 non-European foreigners in the country.

The Turks, though for a considerable period the dominant race, were never very numerous in Algeria. The majority of them were repatriated by the French. The Kuluglis, descendants of Turks by native women--once a distinct race noted for their energy, bravery and pride--have almost ceased to exist as a separate people, being merged in the Moors. Jews have long been settled in Algeria. Some are supposed to have fled thither when expelled from Cyrenaica in the reign of the emperor Hadrian, and others on their banishment from Italy in 1342. The purely ``African'' Jew is now found only in the oases in the extreme south of the country. In the towns the ``native'' Jews have intermarried with later arrivals from Europe. A remarkable feast is kept annually by the Algerian Jews to commemorate the defeat by the Turks of the emperor Charles V.'s attempt to capture Algiers (1541). The Jews, who enjoyed religious freedom under the Mahommedans, believed that the success of the Spaniards would but lead to their own persecution.

Chief Towns.--The chief towns are Algiers, the capital and principal seaport, with a population (1906), including Mustapha and other suburbs, of 154,049; Oran (100,499),2 a western seaport and capital of the department of the same name, and Constantine (46,806), an inland town, capital of the department of Constantine. Besides Algiers and Oran the principal seaports are Bona (36,004), Mostaganem (19,528), Philippeville (16,539), Bougie (10,419), Cherchel (4733) and La Calle (2774). Inland, besides Constantine, are the important towns of Tlemcen ( 24,060), Sidi-bel-Abbes (24,494), Mascara (18,989) and Blida (16,866). In the Sahara are Biskra (4218), El Wad (7586), Tuggurt (2073) and Wargla (3579). All these places are separately noticed.

Nemours (1229) is a seaport near the Moroccan frontier, which formerly bore an Arabic name pregnant with its history --Jamaa-el-Ghazuat (``rendezvous of the pirates''). The surrounding country is rich in mineral wealth. Arzeu (3085) occupies a site on the western side of the gulf of the same name. It has a good harbour, is the outlet for the produce of several fertile valleys, and the starting-point of a railway which penetrates into the Sahara. This railway passes Saida (6256), 106 m. south of Arzeu, one of the capitals of Abd-el-Kader, and serves to bring down from the high plateaus their rich crops of esparto grass. Four miles S.E. of Arzeu is a Berber village, where are interesting ruins of a Roman settlement, identified by some authorities as the Portus Magnus of Pliny; other authorities claim Oran as occupying the site of Portus Magnus. In the vicinity are the famous quarries of Numidian marbles. Tenes (3176) is a seaport situated about 100 m. east of Arzeu on the site of the Phoenician town, afterwards the Roman colony, of Cartenna. Outside the town to the west is a public garden in which are several Roman tombs with inscriptions. Between Tenes and Algiers are Tipasa (q.v.) and Castiglione (1634), formerly called Bu-Ismail, both pleasant watering-places. Five miles inland west of Castiglione is Kolea (2932), a town dating from 1550 and originally peopled by Moslem refugees from Spain. It was destroyed by earthquake in 1825 and has been rebuilt largely in European style. It contains the kubba of a celebrated marabout, Sidi Embarek, who lived in the 17th century. Dellys (3275), 50 m. by sea E. of Algiers, has a small harbour sheltered from the W. and N.W. winds only. It is a walled town regularly laid out, built by the French on the site of the Roman Ruscurium, the western ramparts of which may still be seen. Jijelli (4878), on the eastern side of the Gulf of Bougie, occupies the site of the Roman colony of Igilgilis. The old town, built on a rocky peninsula, was completely destroyed by earthquake in 1856. A new town arose eastward of the former site, which is now restored as a citadel. Twenty miles by sea west of Philippeville is Collo (2258), a city of considerable importance during the Roman occupation. It was the Kollops Magnus of Ptolemy.

Twenty-three miles S.W. by rail from Algiers is Bufarik (the ``hanging well''); pop. 5980. A thoroughly French town, it dates from 1835, when General Drouet d'Erlon established there an entrenched camp on a hillock in the midst of a pestilential swamp. Soon afterwards Marshal Clausel began to build a regular city, which was at first called Medina Clausel in his honour. The draining of the site and neighbourhood was a costly undertaking, and was only accomplished by the sacrifice of many lives. The town, surrounded by vast orchards and farms, is now one of the most flourishing in the country; and the most important market in the colony for the sale of cattle and agricultural produce is held there. Sixty-three miles S.W. of Algiers is Medea (4030)--supposed to stand on the site of a Roman town--finely situated on a plateau 3000 ft. above the sea. It is surrounded by a wall pierced by five gates. An ancient aqueduct is built into the eastern side of the wall. The town, which was chosen by the Turks as capital of the beylik of Titeri, is now French in character. Miliana (3991), which occupies the site of the Roman Milliana, lies about midway between Blida and Orleansville, is 2400 ft. above the sea, and is built on a plateau of the Zakkar mountains, commanding magnificent views of the valley of the Shelif. It possesses few remains of antiquity. An old Moorish minaret has been turned into a clock tower. The town, which is walled, has been rebuilt by the French. The chief streets are bordered by trees and have streams of water running down either side. Hammam R'Irha to the N.E. of Miliana, noted from the time of the Romans for its thermal springs, occupies a picturesque position 1800 ft. above the sea. Being the only place within easy distance of western Europe where patients can take with safety a course of baths during the winter months, it has become a resort of invalids. Orleansville (3510), on the extensive plain of the Shelif, 130 m. S.W. by rail from Algiers. and 132 m. N.E. from Oran, is an important military station. The basilica of St Reparatus, discovered in 1843, was allowed to be used as a public stable and has been completely destroyed. There was in it a beautiful mosaic of which, fortunately, drawings exist. From this it appears that the church was built in A.D. 324, and that St Reparatus, bishop of the diocese, was buried in it in 475. Orleansville occupies the site of the Roman Castellum Tingitanum.

Ninety miles S.W. of Bougie is Aumale (2350), a town and military post established by the French in 1846 on the site of the ancient Auzia. The Roman town was founded in the reign of Augustus, and it flourished for two centuries before it disappeared from history. Out of the materials of the ancient city the Turks built a fort, which at the time of the French occupation was itself a heap of ruins. Setif (12,261), the Sitifis Colonia of the Romans, is 50 m. S.E. of Bougie and 97 m. by rail W. of Constantine. It stands 3573 ft. above the sea, and is the junction of several great lines of communication. Its market is attended by Kabyles, Arabs of the plateaus and people from the Sahara. The town has been entirely rebuilt in the French style. Most of the Roman ruins, even those existing at the time of the French occupation (1839), have disappeared. The walls of the Roman city, restored probably by the Byzantines, have been incorporated in the French walls, which are pierced by four gates. Batna (5279), a walled town 3350 ft. above the sea, 50 m. S. of Constantine by the railway to Biskra, commands the passage of the Aures mountains by which the nomads of the Sahara were wont to enter the Tell. Its importance rests on its strategic position. On the railway between Constantine and Bona and 76 m. from the latter, is Guelma (6584), the Roman Kalama, finely situated on the right bank of the Seybuse. The French occupied the place in 1836 and built their town out of the Roman ruins. Thirty miles S.E. of Guelma is Suk Ahras (7602), a station on the railway to Tunis, identified with the Roman city Tagaste, the birthplace of St Augustine.

Towns in the Sahara.--On the southern slopes of the Great Atlas, 2437 ft. above the sea, looking out on the Saharan desert, and 200 m. in a straight line S.W. of Algiers, is the ancient town of El Aghuat (erroneously written Laghouat); pop. 5660. It formerly belonged to Morocco, by whom it was ceded to the Turks towards the close of the 17th century. It was stormed on the 4th of December 1852 by the French, who almost entirely destroyed the Arab town. The modern town contains little of interest, but is an important military station. One hundred and twelve miles S. of El Aghuat, and 36 m. W.N.W. of Wargla, is Ghardaia (pop. 7868), the capital of the Mzab country, annexed by France in 1882. This country consists of seven oases, five in close proximity and two isolated. The town of Ghardaia (in the local documents Taghardeit) is situated on a mosque-crowned hill in the middle of the Wadi Mzab, 1755 ft. above the sea. Ghardaia, which is divided by walls into three quarters, is built of limestone and the houses are in terraces one above the other. The central quarter is the home of the ruling tribe, the Beni-Mzab. The eastern quarter belongs to the Jews, of whom there are about 300 families; the western is occupied by the Medabia, Arabs from the Jebel Amur. The gardens belong exclusively to the Beni-Mzab. According to native accounts the town was founded about the middle of the 16th century. Aghrem Baba Saad, a small ruined town to the west of Ghardaia, is the fortified post in which the Beni-Mzab took refuge when the Turks under Salah Rais (about 1555) attempted unsuccessfully to subjugate the country. Next to Ghardaia the most important Mzabite town is Beni-Isguen (pop. 4916), an active trading centre. Guerrara, one of the two isolated oases, 37 m. N.E. of Ghardaia, contains a flourishing commercial town with 1912 inhabitants. The caravan route south from Ghardaia brings the traveller, after a journey of 130 m., to the oasis and town of El Golea (pop. about 2500). The town consists of three portions--the citadel on a limestone hill, the upper and the lower town--separated by irregular plantations of date trees. The place is an important station for the caravan trade between Algeria and the countries to the south. It was occupied by the French under General Gallifet in 1873. El Golea was originally a settlement of the Zenata Berbers, by whom it was known as Taorert, and there is still a considerable Berber element in its population. The full Arab name is El Golea'a el Menia'a, or the ``little fortress well defended.''

Archaeology.--Algeria is rich in prehistoric memorials of man, especially in megalithic remains, of which nearly every known kind has been found in the country. Numerous flints of palaeolithic type have been discovered, notably at Tlemcen and Kolea. Near Jelfa, in the Great Atlas, and at Mechera-Sfa (``ford of the flat stones''), a peninsula in the valley of the river Mina not far from Tiaret in the department of Oran, are vast numbers of megalithic monuments. In the Kubr-er-Rumia--``grave of the Roman lady'' (Roman being used by the Arabs to designate strangers of Christian origin)--the Medrassen and the Jedars, Algeria possesses a remarkable series of sepulchral monuments. The Kubr-er-Rumia--best known by its French name, Tombeau de la Chretienne, tradition making it the burial-place of the beautiful and unfortunate daughter of Count Julian--is near Kolea, and is known to be the tomb of the Mauretanian king Juba II. and of his wife Cleopatra Selene, daughter of Cleopatra, queen of Egypt, and Mark Antony. It is built on a hill 756 ft. above the sea. Resting on a lower platform, 209 ft. square, is a circular stone building surmounted by a pyramid. Originally the monument was about 130 ft. in height, but it has been wantonly damaged. Its height is now 100 ft. 8 in.: the cylindrical portion 36 ft. 6 in., the pyramid 64 ft. 2 in. The base, 198 ft. in diameter, is ornamented with 60 engaged Ionic columns. The capitals of the columns have disappeared, but their design is preserved among the drawings of James Bruce, the African traveller. In the centre of the tomb are two vaulted chambers, reached by a spiral passage or gallery 6 1/2 ft. broad, about the same height and 489 ft. long. The sepulchral chambers are separated by a short passage, and are cut off from the gallery by stone doors made of a single slab which can be moved up and down by levers, like a portcullis. The larger of the two chambers is 142 ft. long by 11 ft. broad and 11 ft. high. The other chamber is somewhat smaller. The tomb was early violated, probably in search of treasure. In 1555 Salah Rais, pasha of Algiers, set men to work to pull it down, but the records say that the attempt was given up because big black wasps came from under the stones and stung them to death. At the end of the 18th century Baba Mahommed tried in vain to batter down the tomb with artillery. In 1866 it was explored by order of the emperor Napoleon III., the work being carried out by Adrian Berbrugger and Oscar Maccarthy.

The Medrassen is a monument similar to the Kubr-er-Rumia, but older. It was built about 150 B.C. as the burial-place of the Numidian kings, and is situated 35 m. S.W. of Constantine. The form is that of a truncated cone, placed on a cylindrical base, 196 ft. in diameter. It is 60 ft. high. The columns encircling the cylindrical portion are stunted and much broader at the base than the top; the capitals are Doric. Many of the columns, 60 in number, have been much damaged. When the sepulchral chamber was opened in 1873 by Bauchetet, a French engineer officer, clear evidence was found that at some remote period the tomb had been rifled and an attempt made to destroy it by fire.

The Jedars (Arab. ``walls'' or ``buildings'') are in the department of Oran. The name is given to a number of sepulchral monuments placed on hill-tops. A rectangular or square podium is in each case surmounted by a pyramid. The tombs date from the 5th to the 7th century of the Christian era, and lie in two distinct groups between Tiaret and Frenda, a distance of 35 m. Tiaret (pop. 5778), an ancient town modernized by the French, can be reached by railway from Mostaganem. Near Frenda (2063), which has largely preserved its old Berber character, are numerous dolmens and prehistoric rock sculptures.

Algeria contains many Roman remains besides those mentioned and is also rich in monuments of Saracenic art. For a description of the chief antiquities see the separate town articles, including, besides those already cited, Lambessa, Tebessa, Tipasa and Timgad.

Agriculture.--Ever since the time of the Romans Algeria has been noted for the fertility of its soil. Over two-thirds of the inhabitants are engaged in agricultural pursuits. More than 7,500,000 acres are devoted to the cultivation of cereals. The Tell is the grain-growing land. Under French rule its productiveness has been largely increased by the sinking of artesian wells in districts which only required water to make them fertile. Of the crops raised, wheat, barley and oats are the principal cereals. A great variety of vegetables and of fruits, especially the orange, is exported. A considerable amount of cotton was grown during the American Civil War, but the industry afterwards declined. In the early years of the 20th century efforts to extend the cultivation of the plant were renewed. A small amount of cotton is also grown in the southern oases. Large quantities of crin vegetal (vegetable horse-hair) an excellent fibre, are made from the leaves of the dwarf palm. The olive (both for its fruit and oil) and tobacco are cultivated with great success. The soil of Algeria everywhere favours the growth of the vine. The country, in the words of an expert sent to report on the subject by the French government, ``can produce an infinite variety of wines suitable to every constitution and to every caprice of taste.'' The culture of the vine was early undertaken by the colonists, but it was not until vineyards in France were attacked by phylloxera that the export of wine from Algeria became considerable. Algerian vineyards were also attacked (1883) despite precautionary measures, but in the meantime the worth of their wines had been proved. In 1850 less than 2000 acres were devoted to the grape, but in 1878 this had increased to over 42,000 acres, which yielded 7,436,000 gallons of wine. Despite bad seasons and ravages of insects, cultivation extended, and in 1895 the vineyards covered 300,000 acres, the produce being 88,000,000 gallons. The area of cultivation in 1905 exceeded 400,000 acres, and in that year the amount of wine produced was 157,000,000 gallons. By that time the limits of profitable production had been reached in many parts of the country. Practically the only foreign market for Algerian wine is France, which in 1905 imported about 110,000,000 gallons.

Fishery is a flourishing but not a large industry. The fish caught are principally sardines, bonito, smelts and sprats. Fresh fish are exported to France, dried and preserved fish to Spain and Italy. Coral fisheries exist along the coast from Bona to Tunis.

Minerals.--Algeria is rich in minerals, found chiefly in the department of Constantine, where iron, lead and zinc, copper, calamine, antimony and mercury mines are worked. The most productive are those of iron and zinc. Lignite is found in the department of Algiers and petroleum in that of Oran. Immense phosphate beds were discovered near Tebessa in 1891. They yielded 313,500 tons in 1905. Phosphate beds are also worked near Setif, Guelma and Ain Beida. There are more than 300 quarries which produce, amongst other stones, onyx and beautiful white and red marbles. Algerian onyx from Ain Tekbalet was used by the Romans, and many ancient quarries have been found near Kleber in the department of Oran, some being certainly those from which the long-lost Numidian marbles were taken. Salt is collected on the margins of the shats.

Shipping and Commerce.--The carrying trade between Algeria and France is confined, by a law passed in 1889, to French bottoms. The largest port is Algiers, after which follow Oran, Philippeville and Bona. There is a considerable coasting trade. The average number of vessels entering and clearing Algerian ports each year has been, since 1900, about 4000, with a total tonnage of some 6,500,000. In the coasting trade some 12,000 small vessels are engaged.

Under French administration the commerce of Algeria has greatly developed: The total imports and exports at the time of the French occupation (1830) did not exceed L. 175,000. In 1850 the figures had reached L. 5,000,000; in 1868, L. 12,000,000; in 1880, L. 17,000,000; and in 1890, L. 20,000,000. From this point progress was slower and the figures varied considerably year by year. In 1905 the total value of the foreign trade was L. 24,500,000. About five-sixths of the trade is with or via France, into which country several Algerian goods have been admitted duty-free since 1851, and all since 1867. French goods, except sugar, have been admitted into Algeria without payment of duty since 1835. After the increase, in 1892, of the French minimum tariff, which applied to Algeria also, foreign trade greatly diminished.

The chief exports are sheep and oxen, most of which are raised in Morocco and Tunisia, and horses; animal products, such as wool and skins; wine, cereals (rye, barley, oats), vegetables, fruits (chiefly figs and grapes for the table) and seeds, esparto grass, oils and vegetable extracts (chiefly olive oil), iron ore, zinc, natural phosphates, timber, cork, crin vegetal and tobacco. Of these France takes fully three-quarters. The import of wool, exceeds the export. Sugar, coffee, machinery, metal work of all kinds, clothing and pottery are largely imported. Of these by far the greater part comes from France. The British imports consist chiefly of coal, cotton fabrics and machinery.

Communications.--Algeria possesses a railway system covering over 2000 m. A decree of 1857 granted to the Paris-Lyons Company the right to construct a line linking Algiers with Oran (266 m.) and Constantine (290 m.) and shorter lines joining the seaports to the trunk line, notably Philippeville to Constantine (54 m.). These lines were opened between 1862 and 1871, but it was not until 1879 that a general scheme for railway construction was adopted. A trunk line runs from the frontier of Morocco at Lalla Maghnia, 44 m. W. of Tlemcen, across the Tell to the Tunisian frontier, whence it is continued to the city of Tunis; while traverse railways connect the seaports with the trunk line and with towns to the south, the Philippeville line being continued to Biskra. From Arzeu a line goes south across the plateaus and crossing the Ksur range at a height of 4211 ft. enters the Sahara. Passing Ain Sefra and Figig (372 m. from Arzeu) the line is continued towards Tuat. The normal gauge of the railways is 4 ft. 8 1/2 in.; a few ``light lines'' have a gauge of 3 ft. 3 in. Algeria is also traversed by a network of roads constructed by the French, of which the routes nationales alone are 2000 m. in length. There are complete postal and telegraphic facilities in all parts of the colony save the Saharan Territories, and cable communication with France.

Central Government.--By the Turks the country was divided into four provinces--Algiers and Titeri in the centre and south, Constantine in the east and Mascara or Oran in the west.3 The last three were governed by beys dependent upon the representative of the Porte resident at Algiers. The Turkish governors were in the 17th century replaced by deys (see below, History.) The French rule was at first (1830) purely military. In 1834 the post of governor-general was created. Under the direction of the ministry of war that official exercised nearly all the executive power. At the same time a civil administration and consultative council were formed. The principle of unity of authority was set aside by the second republic in 1848, when many of the public services were attached to the corresponding ministries in Paris, and the departments organized on the metropolitan model by division into arrondissements and communes and by placing a prefect at their head. Under Napoleon III. the governor- generalship was abolished, a minister of Algeria and the colonies created (24th of June 1858), and the whole administration conducted from Paris. At the same time the powers of the prefects were augmented and each department given a general council. This arrangement was not of long duration. By decree of the 24th of November 1860, the ministry of Algeria and the colonies was abolished and the office of governor-general re-established with increased powers. This regime, strongly military in its type, ended with the fall of the second empire. After a brief transitional period, a decree of the 29th of March 1871 placed at the head of Algeria a civil governor-general and gave the control in Paris to the ministry of the interior. In 1876, on the initiative of General Chanzy, then governor-general, that official was accorded the right to correspond direct with all the ministers in Paris. This concession led, however, to the diminution of the authority of the governor-general, whose powers were, step by step, absorbed by the various ministries in France. It had its logical end in the system adopted in 1881 and known as the rattachement. Under this system the plan of 1848 was carried out more completely, every department of state being placed under one or other of the ministries in Paris, whilst the governor- general became little more than an ornamental personage. After lasting fifteen years the rattachement was, with the approval of the legislature, abrogated by decree dated the 31st of December 1896. The opposing principle, that of concentrating power in the hands of the governor-general, was re-affirmed, but in practice was modified by the retention of the direction from Paris of a few of the public services. The decree of 1896, which was of a provisional character, was replaced by another, dated the 23rd of August 1898, defining the powers of the governor-general under the new scheme. By a law of the 19th of December 1900, Algeria was constituted a legal personality, with power to own goods, contract loans, &c., and a decree of 1901 placed the customs department, until then directed from Paris, under the control of the governor-general, whose hands were also strengthened in various minor matters.

It will be seen that the form of government is entirely dependent on the will of France. The French chambers alone possess the legislative power, though in the absence of express legislation decrees of the head of the state have the force of law. To the legislature in Paris Algeria elects three senators and six deputies (one senator and two deputies for each department). The franchise is confined to ``citizens,'' in which category the native Jews are included by decree of the 24th of October 1870. The Mahommedans, who number nearly eight-ninths of the population, are not, however, ``citizens'' but ``subjects,'' and consequently have not the vote. They can, however, acquire ``citizenship'' at their own request, by placing themselves absolutely under the civil and political laws of France (decree of 1865, confirmed in 1870). The number of Mahommedans who avail themselves of this rule is very small; naturalizations do not exceed an average of thirty persons a year. For certain specified objects, financial and municipal, Mahommedans are, however, permitted to exercise the franchise.

The actual form of government may be summarized thus:-- At the head of the administration in Algeria is a governor- general, who exercises control over all branches, civil and military, of the administration, except the services of justice, public instruction and worship (as far as concerns Europeans) and the treasury. He corresponds directly with thn other Barbary states; draws up the budget, and contracts loans on behalf of the colony. The governor-general is assisted by:--

(1) The Council of Government, a purely advisory body, composed entirely of high officials; (2) A Superior Council, composed partly of elected and partly of nominated members, including representatives of the Mahommedans. Its duty is to deliberate upon all administrative matters, including the budget, and it possesses certain powers over the finances; (3) The Financial Delegations (created by decree in 1898), an elective body whose duty is to investigate all matters affecting taxation and to vote the budget. The delegations consist of representatives of (a) ``colonists,'' i.e. the rural community; (b) taxpayers, being citizens other than ``colonists,'' i.e. the urban community; (c) the Mahommedan population. The last section is partly elective and partly nominated. A proportion of the members of the delegations are elected to the superior council. Local Government.--The departments, presided over by prefects, are divided into territoires civils and territoires du commandant. In the regions under civil administration the local organization closely resembles that of France. The country is divided into arrondissements and communes, with most of the apparatus of self-government enjoyed by the corresponding units in France. The canton (in France a judicial area) has, however, no existence in Algeria. In the territoires du commandant, which are the districts farthest from the coast, and in which the European population is small, the prefect is replaced by a high military officer, who exercises all the functions of a prefect.

The prefect of each department is assisted by a general council, consisting of members elected by the citizens and of nominated representatives of the Mahommedan population. The powers of the council correspond to those of the councils in France. Communes are of three kinds: (1) those with full powers, (2) mixed, (3) native. In those of the first kind, modelled on the French communes, the Mahommedans possess the municipal franchise. The ``mixed'' communes are under an administrator nominated by the governor-general and assisted by a municipal council composed of Europeans and natives. These communes are large areas, each containing several towns or villages. In the territoires du commandant the mixed commune is presided over by a military officer who fulfils the duties of mayor. Native communes are organized on the same plan as those last mentioned. It will be seen that communes do not correspond with any natural unit. The unit among the Mahommedans is the douar, a tribal division administered by a cadi. The communes with full powers have each for centre a town with a considerable European population.

By decree of the 14th of August 1905, the frontier between Saharan territory dependent on Algeria and that attached to French West Africa was laid down. The Algerian Sahara was divided into four territories, officially named Tuggurt, Ghardaia, Ain Sefra and the Saharan Oases (Tuat, Gurara and Tidikelt). The governor-general represents the territories in civil affairs; the budget is distinct from that of Algeria and an annual subvention is provided by France.

Finance.--Revenue is derived chiefly from direct taxation, customs and monopolies. The heaviest item of expenditure chargeable on the Algerian budget is on public works, posts and telegraphs and agriculture. Algeria has had a budget distinct from that of France since 1901. This budget includes all the expenses of Algeria save the cost of the army (estimated at L. 2,000,000 yearly) and the guarantee of interest on the railways open before 1901. Both these items are borne by France. The Algerian budget for 1906 showed revenue and expenditure balancing at L. 3,820,000. The country has a debt (1905), including capital, annuities and interest, of some

Defence.--The military force constitutes the XIX. army corps of the French army. There are in addition a territorial army reserve and a special body of troops, largely Arab, for the defence of the Saharan territory. The troops quartered in Algeria exceed 50,000. The defence of the coast is provided by the French navy.

Land Tenure.--The colonization of Algeria by the French has been greatly hampered by the system of land tenure which they found in force. Except among the Kabyles, private property in land was unknown. Amongst the Arabs, lands were either held in common by a whole tribe, under a tenure known as the arch or sabegha, or sometimes, especially in the, towns, under a modified form of freehold (melk) by the family. At the same time the boundaries of property were ill defined and difficult to determine. This system made it impossible for French immigrants to obtain land by lawful transfer. The only lands at the outset available for settlement were, in fact, the confiscated domains of the dey. The obvious solution of the difficulty was to encourage the free movement of real estate by substituting private ownership for the traditional system. Before doing this, however, it was necessary to define the limits of tribal properties already existing--a work of great difficulty--with a view to their ultimate division, and at the same time to guard against any premature traffic in the rights of Arabs in the lands about to be divided. A senatus-consulte of 1863 laid the basis for the change in the land system by providing (1) for the delimitation of the territory of each tribe, (2) for the repartition of the territory thus delimited among newly formed tribal divisions (douars or communes), and (3) for the recognition of private ownership by the issue of title deeds for such individual or family property (melk) as already existed. The purpose of this excellent law, which would have laid firmly the basis for gradual change, was defeated by the impatience of the French colonists. At the instance of their representatives in the chambers it was abandoned in 1870, and was not revived till seventeen years later. A law was passed in 1873, and amended in 1887, legalizing the immediate conversion of tribal and family property into private freehold. The result has been disappointing. For the most part, the Arab tribes have been reluctant to avail themselves of their new powers, and where they have done so the hasty reversal of the traditions of centuries has proved demoralizing to the natives, without any sufficient equivalent in the way of healthy French colonization. The main profit has been reaped by Jewish usurers.

The state domains were exhausted by 1870, but were again replenished by the large confiscations which followed the Arab revolt of 1871. Government lands were originally given free to applicants, but with a provisional and insecure title, which made it impossible for poor colonists to borrow money on their land. This was modified by a law of 1851. But ultimately, the results not being satisfactory, the precedent of Australia was followed, and by a law of 1860 domain lands were sold publicly at a fixed price. This had the effect of attracting more and a better class of immigrants, but was none the less reversed in 1881.

In September 1904, a new scheme, intended to attract more European settlers, was adopted. The lands of the state--other than woods and forests--but especially the barren lands and brushwoods situated in the plains, were offered for colonization, to be disposed of (1) by sale at a fixed price, (2) by auction, and (3), in certain cases, by agreement. Purchasers were to be Frenchmen, or Europeans naturalized as French citizens, who had never held ``colonization lands''; and they were obliged, under pain of forfeiture, either to take up residence themselves on their property within six months and to live on it and exploit it for a period of ten years, or else to place on the land another family fulfilling the same conditions. If the purchaser farmed the land himself and made satisfactory progress, the period of obligatory residence was reduced to five years. When the interests of colonization required it, free gifts of land might be made; in which case the grantee must himself exploit his concession. In no case might land acquired under this scheme be let to natives until after the expiration of ten years.

For the purpose of creating villages, land was put at the disposition of societies or individuals, who undertook to people them with immigrants fulfilling the same conditions as independent settlers. Two-thirds of the villagers were to be French immigrants, the other third Frenchmen or naturalized Frenchmen already settled in Algeria. To favour the establishment of special industries, the governor-general was given power to authorize the introduction of foreign instead of French immigrants. The societies or individuals undertaking village settlements must do so from philanthropic motives, inasmuch as within two years of the founding of a village, the land, under pain of forfeiture to the state, must be transferred gratuitously to the villagers. As will be seen, settlement on the land by Europeans is hampered by official restrictions, especially by the stringent regulations as to residence.

Justice.--Two judicial systems exist in Algeria--native and French. Native courts decide suits between Mahommedans. From the decision of the cadis appeal lies to the French courts. The French system provides, for civil cases, a court of first instance in each of the sixteen arrondissements into which the country is divided. A court of appeal sits at Algiers. There are also tribunals of commerce and justices of the peace with extensive jurisdiction. The criminal courts are organized as in France. Trial by jury has been introduced; but as natives are not allowed to act as jurymen this has often led to serious miscarriages of justice and to excessive severities.

Whilst modifications of the law require special legislation or decree, it has been legally decided that all laws in force in France before the conquest of the country (i.e. those anterior to the 22nd of July 1834) are in force in Algeria. In practice the courts allow themselves wide latitude in applying this principle.

Education.--The system of education is complicated by the co-existence of Mahommedan and Christian communities. Before the arrival of the French two kinds of instruction were given, reading and writing being taught in the ordinary schools and higher education--largely theological--in medressas (colleges), usually attached to the chief mosques. Attempts by the French to improve the education of the natives were at first marked by hesitation and long periods in which little or nothing was done. The provision for the instruction of the European and Jewish population was also inadequate. In 1883 a law was passed for the reorganization of the systems in force, and primary instruction was made compulsory for Europeans and Jews, whilst in the case of Mahommedans discretion in the establishment of schools was vested in the governor- general.

Attempts are made to assimilate the Mahommedan population by means of Franco-Arab primary and secondary schools, which supplement the purely French and purely Arab establishments of the same character. These attempts meet with little success, owing in part to racial prejudice and in part to the indifference of the Arabs to education. Few Moslems attend the secondary schools. Purely Mahommedan higher schools exist at Algiers, Tlemcen and Constantine. From these establishments the ranks of native officials are recruited. There is one secondary school for Moslem girls. The education provided for Europeans resembles in most respects that given in France. (The lycees at Algiers, Oran and Constantine are open to Mahommedans, but few take advantage of them.) Besides the government schools there are establishments conducted by clerics and laymen. The best girls' schools are generally those kept by nuns. At Algiers there is an establishment with faculties of law, medicine and pharmacy, science and letters. At Oran is a college for European girls. The scholars attending primary schools number about 150,000 (over 100,000 being Europeans and some 15,000 Jewish) and those at secondary schools about 6000. (F. R. C.)

HISTORY

Africa Minor.

From a geographical point of view Algeria, together with Morocco and Tunisia, from which it is separated only by artificial and purely political frontiers, forms a distinct country. which it is convenient to designate by the name of Africa Minor. Both historically and geographically, Africa Minor belongs much more to the Mediterranean world than to the African. All the foreign invaders who successively established their dominion over this country either crossed the Mediterranean or followed its shores. The Phoenicians, the Romans, the Vandals, the Byzantines, the Arabs, the Turks and the French, all came from the east or from the north. The history of Africa Minor is the history of all those foreigners who have successively endeavoured to exploit this land, the history of their divers civilizations struggling against an ever-renascent barbarism.

The political divisions of Africa Minor have changed many times, for, as the country has no natural centre, many towns have aspired to play the role of capital. The rivalry of these towns is intimately connected with the struggles and insurrections which have stained the land with blood. The existing division--viz. Morocco, Algeria and Tunisia--dates back to the time of the Turkish dominion. It is since that time only that the expression Algeria has been in use.

Struggle with Spain.

At the beginning of the 16th century the native dynasties which divided Africa Minor between them--the Marinides at Fez, the Abd-el-Wahid at Tlemcen, and the Hafsides at Tunis--were without strength and without authority. Two nations, then at the height of their power, Spain and Turkey, disputed the empire of the Mediterranean. The Spaniards took Mers-el-Kebir (1505), Oran (1509), and Bougie and Tripoli (1510). Two Turkish corsairs, Arouj and his brother, Khair-ed-Din (otherwise known as Barbarossa), at first established in the island of Jerba and afterwards at Jijelli, disputed with the Spaniards the dominion of the country. Arouj seized Algiers (1516); Khair-ed-Din, succeeding him in 1518, did homage for his conquest to the sultan at Constantinople, who named him beylerbey and sent him soldiers (1519). Then began the struggle of the Turks with Spain. In 1541 the emperor Charles V. undertook a great expedition against Algiers. He succeeded in landing, and proceeded to attack the town. But during the night of the 26th of October a violent storm destroyed a great part of his fleet. His provisions and his ammunition were lost, his army was compelled to retreat with considerable loss, and the emperor had to re-embark with the remnant of his troops. This check completely discouraged the Spaniards and assured success to the Turks. The Spanish garrisons established in the coast towns, badly paid and left without reinforcements, had difficulty in defending themselves. In the end, the only towns the Spaniards retained on the Algerian coast were Oran and Mers-el-Kebir. These two towns, taken by the Turks in 1708 and retaken by the Spaniards in 1732, were finally abandoned in 1791.

Barbary corsairs.

Under the Turkish dominion Algeria had originally at its head a beylerbey resident at Algiers. He controlled three beys:--the bey of Titeri in the south, the bey of the east at Constantine, and the bey of the west who resided at Mascara and afterwards at Oran. These three beys existed till 1830. The beylerbeys were replaced in 1587 by pashas sent triennially by the Porte. But the authority of these pashas, strangers to the country, was always precarious. They found themselves, in fact, in conflict with two forces, which in principle were in their service, but which in reality held the power--the taiffe des reis, otherwise called the corporation of the corsairs (see BARBARY PIRATES), and the janissaries, a kind of military democracy in which each member was promoted according to seniority. In 1669 the corsairs drove out the pasha, and put into his place a dey elected by themselves. After some fruitless attempts Turkey ceased to send pashas to Algiers--where they were not allowed even to land--and thus recognized the de facto independence of this singular republic. The authority of the deys, moreover, was scarcely more solid than that of the pashas. They trembled before the janissaries, who from the 18th century elected and deposed them at their pleasure.

The relations which the European powers were able to maintain with northern Africa were at that time difficult and uncertain. Ships trading in the Mediterranean were seized by the corsairs, who pillaged the coasts of Europe, carried off their captives to Algiers, and destroyed the fishing and commercial settlements founded by the Marseillais on the shores of Africa. The Christian governments either uttered useless and impotent complaints at Constantinople, or endeavoured to negotiate directly with Algiers, as in the case of the negotiations of Sanson Napollon during the ministry of Richelieu. More rarely their patience became exhausted, and ships were sent to bombard this nest of pirates. Two naval demonstrations were made by France during the reign of Louis XIV., one by Abraham Duquesne in 1682, and the other by Marshal Jean d'Estrees in 1688, but these repressive measures were too intermittent to produce a durable effect.

In 1815 at the congress of Vienna, and in 1818 at the congress of Aix-la-Chapelle, the powers endeavoured to concert measures to put an end to the Barbary piracy. Nevertheless the naval demonstrations made by Lord Exmouth in 1816, and by a combined English and French squadron in 1819, remained equally fruitless. But the result which the European powers in concert had been unable to achieve, was brought about by the accidental circumstances which led France to undertake alone an expedition against Algiers.

French intervention.

Some difficulties had arisen between France and the dey of Algiers with reference to the debts contracted to Bacri and Busnach, two Algerine Jews who had supplied corn to the French government under the Directory. This question of interest would not have been sufficient in itself to bring about a rupture, but the situation became acute when the dey, Hussein, struck the French consul, Deval, on the face with his fly-flap (April 30, 1827). Thereupon the port of Algiers was blockaded. The minister of war, the duc de Clermont-Tonnerre, would have gone further, but the president of the council, the comte de Villele, opposed the sending of an expedition, while in the Martignac ministry M. de la Ferronays, minister of foreign affairs, was bent upon negotiating. It needed a second insult--the firing on ``La Provence,'' a vessel carrying a flag of truce, in the harbour of Algiers (August 3, 1829)--to spur the French government to further action than an ineffectual blockade. An expedition against Algiers was then decided upon, and Marshal de Bourmont, the minister of war, himself took the command. On the 14th of June 1830 the French troops landed at Sidi-Ferruch. On the 19th of June they beat the enemy at Staoueli. On the 4th of July the fort de l'Empereur was blown up. On the 5th of July Algiers capitulated. Some days later the dey was deported, as well as the greater part of the janissaries. Those who were not married were conveyed immediately to Asia Minor; the rest had permission to remain, but in fact they left the country soon afterwards.

Meanwhile the revolution of July 1830 had broken out in France. The new government found itself very much embarrassed by the situation bequeathed by the Restoration. The more serious section in parliament were frankly opposed to the idea of conquering or of colonizing Algeria; on the other hand, popular sentiment was hostile to evacuation. The French government--fearing to displease the other powers by following up its conquest, and hampered in particular by its engagements towards England, yet conscious that the only means of putting an end to the piracy was to remain--decided provisionally in favour of that intermediate system, called restricted occupation, which consisted in occupying merely the principal seaports and awaiting events. The Algerians extricated the government from its difficulty by attacking the French troops, who were obliged to defend themselves. The natives gained some successes, and it became necessary to avenge the honour of the flag. In this gradual manner were the French led to conquer Algeria.

General Bertrand Clausel, who succeeded Marshal de Bourmont, was one of the few men who at that period dreamed of conquering and colonizing Algeria. His enthusiastic confidence knew no obstacles. If the dey had left, the three beys remained. With the feeble resources at his disposal Clausel undertook an expedition against Bu-Meyrag, the bey of Titeri, took from him Blida and Medea, dismissed him, replaced him by a successor devoted to France, and returned to Algiers after having left a garrison in Medea. Then, not having the means of directly extending the rule of France to the east or west, Clausel devised a system of protectorates. He negotiated directly with the bey of Tunis with a view to installing as beys at Oran and Constantine Tunisian princes who recognized the authority of France. But the events which were taking place in Europe made it imperative to send home a part of the army of Africa, and Medea had to be evacuated. At the same time the negotiations set on foot with the bey of Tunis were censured by the government, and General Clausel was recalled (February 1831).

The period of uncertainty was prolonged under his successors, General Pierre Berthezene (February to December 1831); A. J. M. R. Savary, duc de Rovigo (December 1831 to March 1833), General Avizard (March to April 1833), and General Voirol (April 1833 to September 1834). The French, not yet certain whether or not they would retain Algeria, remained on the defensive. At the time they occupied only the three towns of Algiers, Bona and Oran, with their suburbs, where their situation was moreover singularly precarious. The Arabs would pillage the suburbs and run away. Sometimes they cut off supplies by ceasing to bring provisions to the market, but the French were not to be turned aside by such tactics.

At Algiers the energies of the French were devoted to protecting themselves against the incursions of the Hajutas. This was sufficient to absorb the attention of the general-in-chief, who left the guardianship of the east and west to the initiative of the generals established at Bona and Oran. At Bona, where General Monk d'Uzer was in command till 1836, things went fairly well. At once firm and conciliatory, he had been able to attach to the French cause the natives whom the cruelty of Ahmed, bey of Constantine, had alienated. The occupation of Bougie by General Camille Alphonse Trezel in October 1833 gave the French a footing at another point of this eastern province. But at Oran, where General Desmichels had succeeded General P. F. X. Boyer in the spring of 1833, their situation was much less favourable. There the French had found a redoubtable adversary in the young Abd-el-Kader, who had been proclaimed amir at Mascara in 1832.

Abd-el-Kader.

A man of rare intelligence, a fearless horseman and an eloquent orator, Abd-el-Kader had acquired a great reputation by his piety. He reunited under his sway the tribes that had hitherto been divided, and infused a unique spirit into their resistance. For fifteen years he held the French in check, treating on terms of equality with their government. Moreover, the treaty which General Desmichels had the weakness to sign with him on the 24th of February 1834 greatly improved his position. In pursuance of this treaty, French officers were to represent their country at the court of the amir; while the amir on his part was represented in the three French coast towns, Oran, Arzeu and Mostaganem, by vakils who immediately began to act as masters of the natives. Such was the situation at the period when, the French having at last resolved to keep Algeria, the ordinance of the 22nd of July 1834 laid down the bases of the political and administrative organization of the ``French possessions in the north of Africa,'' at the head of which was placed a governor-general. But this date (July 22, 1834), very important from a judicial point of view, is much less so from a historical point of view. The position of the first governor-general, Jean Baptiste Drouet d'Erlon (1765- 1844), remained fully as precarious as that of his predecessor. During this time the power of Abd-el-Kader increased. Master of the province of Oran, he crossed the Shelif at the appeal of the natives, the people flocking to witness his progress as that of an emperor. He entered Miliana and Medea, where he installed beys of his own choice. All the western part of Algeria belonged to him. General Trezel, who had succeeded General Desmichels at Oran, resolved to march against the amir, but was defeated on the banks of the Macta (June 1835). This defeat shook public opinion. Drouet d'Erlon was recalled and replaced by Marshal Clausel.

In short, five years after the capitulation of Algiers, the French dominion extended as yet over only six coast towns. Clausel, who returned with the same colonial ambitions as in 1830, resolved to conquer the interior of the country. He marched against the amir, defeated him and entered Mascara. Then he proceeded to deliver the inhabitants of Tlemcen, who had been attacked by Abd-el-Kader, and there he left a garrison. Turning towards the east, Clausel organized at Bona the first expedition against Constantine. This failed, and the only result of it was the occupation of Guelma. Clausel was recalled and replaced by General C. M. D. Damremont (February 1837). The task of maintaining the position of France was then divided between Thomas Robert Bugeaud (1784-1849), acting independently in the west, and Damremont, who directed all his efforts towards the east. By the signature of the celebrated treaty of the Tafna (June 1, 1837), Bugeaud made peace with Abd-el-Kader. In return for a vague recognition of the sovereignty of France in Africa, this treaty gave up to the amir the whole of western Algeria. France reserved to herself only Oran and its environs, Mazagran, Algiers and the Metija; she gave up Tlemcen and the Titeri beylik. This was a triumph for Abd-el-Kader, who rerarded the peace as but a truce which would allow him time to gain strength to resume the war under more favourable conditions.

Damremont, on his part, directed a second expedition on Constantine. The town was taken, but Damremont was killed (October 1837). Marshal Sylvain Charles Valee (1773-1846), who replaced him, founded Philippeville to serve as a seaport for the region of Constantine, occupied Jijelli, and at the head of the expeditionary column returned from Constantine to Algiers by the interior, passing through Setif and les Portes de fer. Abd-el-Kader maintained that the French had thus violated the treaty of the Tafna, and began the war again. For two years his power had been increasing. A whole hierarchy of khalifas, aghas and caids obeyed him. He had a regular army of 8000 infantry and 2000 cavalry, without counting 50,000 goums (bodies of Arab horsemen) brought by the khalifas. He was well furnished with war material, possessing magazines and arsenals in the heart of the Tell. He had attacked and subjugated all who were not willing to recognize his authority. Under his influence old rivalries were effaced; at his voice all the tribes joined in the holy war. On the 18th of November 1839 he sent his declaration of war to Marshal Valee, but the impatient Hajutas had already devastated the Metija. Marshal Valee marched against Abd-el-Kader, and at first gained some successes: the French occupied Cherchel, Medea and Miliana. But at the end of 1840 valee was recalled and replaced by Bugeaud, who adopted totally different tactics. The system of Marshal Valee had been the defensive: he multiplied the fortified posts in order to draw the enemy to a spot chosen beforehand. Bugeaud resolutely adopted the offensive, reduced the weight carried by the soldiers in order to increase the mobility of his troops, and carried the war into the province of Oran, from which Abd-el-Kader drew his principal resources. One after the other, all the magazines of the amir--those at Takdempt, Boghar, Taza, Saida and Sebdu--were taken and destroyed. In the spring of 1843 the duc d'Aumale had an opportunity of surprising the smala (camp) of Abd-el-Kader near Taguin. This was a serious blow for the amir, whose determination to continue the contest was, however, as strong as ever. He took refuge in Morocco, and induced that power to declare war on the French on the pretext that they would not give up the frontier post of Lalla-Maghnia. Morocco was soon vanquished. While Francois, prince de Joinville, was bombarding Tangier and Mogador, Bugeaud gained the victory of the Isly (August 1844). Morocco signed a treaty of peace at Tangier on the 10th of September 1844.

The struggle, however, was not ended. Islam made a supreme effort in Algeria. The Dahra and the Warsenis rose at the voice of a fanatic called Bu-Maza (``the goat man''), a Khuan of the order of the Mouley-Taieb. Elsewhere other ``masters of the hour,'' false Bu-Mazas, rose. Abd-el-Kader reappeared in Algeria, which he overran with a rapidity which baffled all pursuit. He beat the French at Sidi Brahim, raided the tribes of the Tell Oranais which had abandoned him, penetrated as far as the borders of the Metija, and reached the Jurjura, where he endeavoured to rouse the Kabyles. But his eloquence offended the narrow and cramped particularism of those little democratic cities, deaf to the sentiment of the common interest. From that time he played a losing game. He returned toward the west, penetrating farther and farther to the south. Badly received by the great aristocratic family of the Walid-sidi- Sheikh, he re-entered Morocco, but the emperor of that country, dreading his influence and fearing difficulties with the French, drove him out. This was the end. On the 23rd of December 1847 Abd-el-Kader surrendered to General Lamoriciere in the plains of Sidi-Brahim. His adversary, Bugeaud, was there no longer. Having failed to persuade the French government to adopt his plans of military colonization, he had retired in June 1847 and had been replaced by the duc d'Aumale.

The surrender of Abd-el-Kader marks the end of the period of the conquest. It is true that Great Kabylia had to be subdued only ten years later, and that terrible insurrections still had to be quelled. But at the end of the reign of Louis Philippe the essential work was accomplished. All that remained was to complete and to secure it.

French progress.

Under the second republic Algeria was governed successively by Generals L. E. Cavaignac (February to April 1848), N. A. T. Changarnier (April to September 1848), V. Charon (September 1848 to October 1850), and A. H. d'Hautpoul (October 1850 to December 1851). The policy followed at this period consisted in assimilating Algeria to France. Important efforts were made to attract French colonists to the country, the colonization of Algeria appearing as a means towards the extinction of pauperism in the mother-country. This point of view suggested numerous projects, as chimerical as they were generous; two millions sterling (50 million francs) were expended with a view to installing Parisian unemployed workmen as colonists, but this attempt failed miserably. The most remarkable military events of this period were (1) the siege and destruction of the oasis of Zaatcha, where the inhabitants, displeased by an alteration in the tax on palms, rose at the voice of a fanatic named Bu-Zian; (2) the ineffectual campaign of Marshal Saint Arnaud in Little Kabylia, where the tribes rose at the instigation of Bu-Magla (``the mule man'') in 1851.

Marshal J. L. C. A. Randon (1795-1871), named governor- general of Algeria after the coup d'etat, had at first to repress in the south a rising of a new ``master of the hour,'' Mahomet ben Abdallah, the sherif of Wargla. A column seized Laghouat (El Aghuat) in December 1852. Si-Hamza, leader of the Walidsidi-Sheikh, an ally of France, indignant at the growing influence of a base-born agitator, pursued him and seized Wargla (1853). In 1854 General Desvaux entered Tuggurt. Henceforth matters remained quiet in the region of the Sahara, and Marshal Randon turned his efforts towards Kabylia. Neither the Romans nor the Turks had been able to subdue this square mountainous tract, of which Bougie, Setif, Aumale and Dellys form the four corners. But in two months (May to June 1857) Marshal Randon made himself master of it, and built in the heart of this country Fort Napoleon (now Fort National), ``the thorn in the side of Kabylia,'' whose batteries commanded all the Kabyle villages of the region.

In 1858 the creation of a ``ministry of Algeria and of the colonies'' brought about the resignation of Marshal Randon. The administrative headquarters of Algeria was then transferred from Algiers to Paris. The ministry of Algeria was entrusted first to Prince Napoleon, and afterwards to the marquis J. N. S. P. de Chasseloup-Laubat (1805-1873). But this office, created at the least prematurely, soon disappeared without causing any regrets. This ephemeral regime lasted from the 24th of June 1858 to the 24th of November 1860. The decree of the 24th of November 1860 transferred the services from Paris back to Algiers, and re-established the functions of governor-general, which were exercised at the end of the second empire first by Marshal Pelissier, duc de Malakoff (December 1860 to September 1864) and then by Marshal Macmahon, duc de Magenta (September 1864 to July 1870). At this period the conception of the Arab kingdom was prevalent. The emperor Napoleon III., in a celebrated letter, wrote that he was as much the emperor of the Arabs as the emperor of the French. Algeria was considered as a kind of great military fief, and the officers who ruled there commonly took the side of the native chieftains against the civil population. European colonization, hampered by the ill-will of the Arab bureaux, then made little progress.

Revolt of 1864-1871.

It was at this period that the great insurrection of the Walidsidi-Sheikh broke out in the Sud Oranais. This powerful family had lived up to that time on a good understanding with France; Si-Hamza, chief of the elder branch, had remained until his death (1861) a faithful ally of France. Thanks to him, the security of the southern frontier was assured. But after his death his son, Si-Sliman, imbued with anti-French sentiments, revolted in 1864 and massacred the Beaupretre column. Several years were occupied in quelling the insurrection. Compelled to guard themselves on the south against the Walid-sidi-Sheikh,the French realized how much they lost by not having the support of these great chieftains. They then accepted the services offered to them by Si-Sliman-ben- Kadour, chief of the younger branch of the Walid-sidi-Sheikh, who maintained tranquillity in the Sud Oranais during the great insurrection of Kabylia in 1871.

The causes of this insurrection were manifold, and, moreover, interdependent: the injury done to the military prestige of France by its defeats in Europe; the fall of the imperial government, in which, in the eyes of the natives, the authority of France was incarnate; and the insults offered with impunity in the streets by the civil population to the officers, who were loved and respected by the Arabs, at the same time that the decree of Adolphe Cremieux accorded to the Algerine Jews the rights of French citizens. The great native chiefs, bewildered and disquieted, thought themselves menaced. The insurrection was inevitable. Mokrani, bach-agha of the Mejana, whom the imperial government had loaded with honours, gave the signal. He had an interview with El Haddad, the sheikh of the Khuans, the religious confraternity of Sidi-Abd-er-Rahman, whose influence was great, and having secured his support in April 1871, Mokrani proclaimed the holy war. At the bidding of El Haddad the whole of Kabylia rose, and numbers of French colonists were massacred; the columns of Colonel Cerez and General F. G. Saussier had to engage in numerous fights. The death of the bach-agha at the battle of Suflat, the submission of the Sheikh El Haddad, and finally the arrest of Bu-Meyrag, brother of Mokrani, mark the declining stages of the insurrection, which was completely suppressed by August 1871. A heavy war contribution was imposed upon the rebels and their lands were sequestrated. The Beni-Manassir, who rose almost at the same time in the Dahra, were subdued soon after. Subsequently the native population of the Algerine Tell remained quiet, the massacre of the colonists at Margueritte many years later being a local and isolated movement.

Since 1870.

Under the third republic Algeria was governed successively by Admiral L. H. de Gueydon (March 1871 to June 1873), General A. E. A. Chanzy (June 1873 to February 1879), J. P. L. Albert Grevy (March 1879 to November 1881), Tirman (November 1881 to April 1891), Jules Cambon (April 1891 to September 1897), Louis Lepine (September 1897 to August 1898), E. J. Laferriere (August 1898 to October 1900), Charles Jonnart (October 1900 to June 1901), A. J. P. Revoil (June 1901 to April 1903), and again Jonnart. During the first years of the new regime a keen reaction was produced against the political system of the imperial government in Africa. The civil territory was considerably enlarged at the expense of the military. An effort was made to attract French colonists to Algeria by gratuitous concessions of land. Some lands were granted in particular to natives of Alsace-Lorraine, who preferred to retain French nationality after the war. Peasants from the south of France, whose vines had been destroyed by the phylloxera, crossed the Mediterranean and established in Algeria an important vineyard. This double current of immigration notably increased the French population of North Africa. The tendency then was to treat Algeria as a piece of France. This assimilative policy attained its culminating point in the so-called decrees of rattachement (1881), in pursuance of which each ministerial department in France was made responsible for Algerine affairs which came by their nature within its jurisdiction.

After a great inquiry held in 1892 by a senatorial committee a reaction was produced in France against this excessive assimilation. The system of rattachement was in great part abandoned, and decentralization was obtained by augmenting the powers of the governor-general, and by granting to Algeria legal personality and a special budget (see above, Central Government.) These reforms appear to have given satisfaction to Algerian opinion. Profoundly troubled as Algeria was in the last years of the 19th century by the anti-Semitic agitation, which occasioned frequent changes of governors, it appears to-day to have turned aside from sterile political struggles to interest itself exclusively in the economic development of the country.

The movement of expansion towards the south was continued under the third republic. In 1873 General G. A. A. Gailifet entered El Golea. In 1882 the oasis of Mzab was annexed. In the Sud Oranais an insurrection, fomented by a marabout named Bu-Amama, broke out in 1881, and the insurgents massacred the European labourers engaged in the collection of alfa (or esparto) grass. But soon the French columns re-established peace, and Bu-Amama had to take refuge in Morocco. In 1883 Si-Hamza, chief of the elder branch of the Wahd-sidi-Sheikh, made his submission, and since then that family has remained devoted to France.

The attempts at penetration into the extreme south, abandoned after the massacre by Tuareg of a mission sent in 1881, under Colonel Paul Flatters, to study the question of railway communication with Senegal, were begun again in 1890, in which year the British government recognized the western Sahara as within the French sphere. Since then military stations and scientific and commercial exploration have increased. But the results of these efforts remained inconsiderable until the spring of 1900, when the French authorities decided to occupy the oases of Gurara, Tuat and Tidikelt. This being accomplished by March 1901, the conquest of the Algerine Sahara was from that time completed, and nothing any longer hindered the attempts to join Algeria and the Sudan across the Sahara. (A. GIR.)

BIBLIOORAPHY.--For a general account of Algeria, see Maurice Wahl, L'Algerie (5th ed., Paris, 1908); P. Leroy-Beaulieu, Algerie et Tunisie (2nd ed., Paris, 1897); J. A. Battandier and L. Trabut, L'Algerie; le sol et les habitants (Paris, 1898), specially valuable for agriculture and fauna; Arthur Girault, Principes de colonisation et de legislation coloniale, Tome iii. ch. i.-viii. (3rd ed., Paris, 1908), containing valuable bibliographies of works relating to legislation, jurisprudence, &c.; Jules Duval, L'Algerie et les colonies francaises (Paris, 1877). The Statistiaue generale de l'Algerie is published periodically by the Algerian government. The British Foreign Office publishes annual Reports on the Trade of Algeria; Sir R. Lambert Playfair's Handbook for Travellers in Algeria (Murray's Handbooks), corrected to 1902, is a capital guide to the country, as is also Algerie et Tunisie (Paris, 1906), in the Guides- Joanne Series; the Bibliography of Algeria (London, 1888), and the Supplement to the Bibliography of Algeria (London, 1898), by Sir Lambert Playfair, contain thousands of entries and many notes. J. A. Battandier and L. Trabut, Flore de l'Algerie (Algiers and Paris, 1884 and onwards), contains a scientific and descriptive catalogue, in several volumes, of the indigenous flora. For the geology of Algeria, see M. A. Pomel, Description stratigraphique generale de l'Algerie (1889), and numerous papers by E. Ficheur, L. Gentil, G. Rolland, P. Thomas, and J. Welsch will be found in the Bull. Soc. Geol. France, and Compt. Rend, Acad. Sci. The volumes of the International Geological Congress review Algerian geology. The French government publication, Exploration scientifique de l'Algerie (20 vols., 1844-1853), gives the results of investigations made in 1840-1842. O. Depont and X. Conpolani, Les Confeeries religiouses musulmanes (Algiers, 1897), and Carte de l,Algerie . . . domaine geographique des confreries (Algiers, 1898), have special reference to the Islamic sects in Algeria. Stephane Gsell's Les monuments antiques de l'Algerie (2 vols., Baris, 1901), one of the publications of the Service des monuments historiques of the colony, is an authoritative and finely illustrated work on the antiquities of Algeria. For archaeology see also the bibliography in AFRICA, ROMAN.

The best best elementary work on the history of Algeria is that of Cat, Petite histoire de l'Algerie (Algiers, 1889). For more profound researches consult: (a) for the Turkish period: H. D. de Gramont, Histoire d'Alger sous la domination turque (1887); Mercier, Histoire de l'Afrique septenirionale (1888-1891); Eugene Plantet, Correspondance des deys d'Alger avec la cour de France (1889--1892); Paul Masson, Histoire dec etablissements et du commerce francais dans l'Afrique barbaresque (1903); General Faure-Biguet, Histoire de l'A.irique septentrionale sous la domination musulmane (1905); (b) for the French period: Camille Rousset, La Conquete d'Alger (8th ed., 1899), Les Commencements d'une conquete; l,Algerie de 1830 a 1840, with atlas (1887), and La Conquete de l'Algerie, 1841- 1857, with atlas (1889); Pelissier, Annales algeriennes (1834); Leon Roches, Trente-deux ans a travers l'Islam (1884-1837); Colonel Trumelet, Histoire de l'insurrection des Guled-Sidi-Cheik (1887); Rinn, Histoire de l'insurrection de 1871 (1891).

The best general maps are those of the Carte de l'Algerie, in numerous sheets, on the scale of 1:50,000 (published by the Service geographique de l'Armee, Paris). (F. R. C.)

1 The name ``Great'' Atlas is more correctly applied to the main range in Morocco.

2 The figures given are not those of the communes, but of the towns proper, certain classes of persons (such as troops, lunatics, convicts) excluded from the municipal franchise not being counted.

3 This western beylik corresponded roughly with the former sultanate of Tlemcen (q.v..)

ALGHERO, a seaport and episcopal see on the W. coast of Sardinia, in the province of Sassari, 21 m. S.S.W. by rail from the town of Sassari. Pop. (1901) 10,779. The see was founded in 1503, but the cathedral itself dates from the 12th century, though it has been reconstructed. The town was strongly fortified by medieval walls, which have to some extent been demolished. It was originally founded by the Doria family of Genoa about 1102, but was occupied by the house of Aragon in 1354, who held it successfully against various attacks until it fell to the house of Savoy with the rest of Sardinia in 1720. Catalonian is still spoken here. Charles V. visited Alghero on his way to Africa in 1541. The coral and fishing industries are the most important in Alghero, but agriculture has made some progress in the district, which produces good wine. There is a large penal establishment containing over 700 convicts. Seven miles to the W.N.W. is the fine natural harbour of Porto Conte, secure in all weather, and on the W. of this harbour is the Capo Caccia, with two stalactite grottos, the finest of which, the Grotta di Nettuno, is accessible only from the sea. The important prehistoric necropolis of Anghelu Ruju was excavated in 1904 61 m. N. of Alghero (Notizie degli Scavi, 1904, 301 seq.).

ALGIDUS MONS, a portion of the ridge forming the rim of the larger crater of the Alban volcano (see ALBANUS MONS) and more especially the eastern portion, traversed by a narrow opening (now called the Cava d'Aglio) of which the Via Latina took advantage, and which frequently appears in the early military history of Rome. That a distinct town existed (Dion. Halic. x. 21, xi. 3) on the mountain is improbable; there must have been a fortified post, but the extensive castle on the hill (Maschio d'Ariano) to the south of the Via Latina is entirely medieval, a fact which has not been recognized by some topographers.

ALGIERS (Fr. Alger, Arab. Jezair, i.e. The Islands), capital and largest city of Algeria, North Africa, seat of the governor- general, of a court of appeal, and of an archbishop, and station of the French XIX. corps d'armee. It is situated on the west side of a bay of the Mediterranean, to which it gives its name, in 36 deg. 47' N., 3 deg. 4' E., and is built on the slopes of the Sahel, a chain of hills parallel to the coast. The view of the city from the sea is one of great beauty. Seen from a distance it appears like a succession of dazzling white terraces rising from the water's edge. The houses being seemingly embowered in the luxuriant verdure of the Sahel, the effect is imposing and picturesque, and has given rise to the Arab comparison of the town to a diamond set in an emerald frame. The city consists of two parts; the modern French town, built on the level ground by the seashore, and the ancient city of the deys, which climbs the steep hill behind the modern town and is crowned by the kasbah or citadel, 400 ft. above the sea. The kasbah forms the apex of a triangle of which the quays form the base.

Extending along the front of the town is the boulevard de la Republique, a fine road built by Sir Morton Peto on a series of arches, with a frontage of 3700 ft., and bordered on one side by handsome buildings, whilst a wide promenade overlooking the harbour runs along the other. Two inclined roads lead from the centre of the boulevard to the quay 40 ft. below. On the quay are the landing-stages, the custom-house and the railway station. At the southern end of the boulevard de la Republique is the square de la Republique, formerly the place Bresson, in which is the municipal theatre; at the other extremity of the boulevard is the place du Gouvernement, which is planted on three sides with a double row of plane trees and is the fashionable resort for evening promenade. The principal streets of the city meet in the place du Gouvernement: the rue Bab Azoun (Gate of Grief) which runs parallel to the boulevard de la Republique; the rue Bab-el-Oued (River Gate) which goes north to the site of the old arsenal demolished in 1900; the rue de la Marine which leads to the ancient harbour, and in which are the two principal mosques. A large part of the modern town lies south of the square de la Republique; in this quarter are the law courts, hotel de ville, post office and other public buildings. The streets in the modern town are regularly laid out; several are arcaded on both sides.

The old town presents a strong contrast to the new town. The streets are narrow, tortuous and inaccessible to carriages. They often end in a cul-de-sac. The principal street is the rue de la Kasbah, which leads up to the citadel by 497 steps. The streets are joined by alleys just wide enough to pass through. The houses, built of stone and whitewashed, are square, substantial, flat-topped buildings, presenting to the street bare walls, with a few slits protected by iron gratings in place of windows. Each house has a quadrangle in the centre, into which it looks, and which is entered by a low, narrow doorway. Shops in the native quarter are simply chambers in the walls of the houses, and open at the front. In these shops the few Moorish industries are carried on, such as embroidery in gold and silver thread, the making of kid slippers of every kind and colour, the manufacture of gold and silver ornaments. To European eyes the native city, with its motley throng of Moors, Arabs, Jews and negroes, is the most interesting sight in Algiers. Various squares are set apart for markets, and here are to be witnessed scenes of the greatest animation.

The public buildings of chief interest are the kasbah, the government offices (formerly the British consulate), the palaces of the governor-general and the archbishop--all these are fine Moorish houses; the ``Grand'' and the ``New', Mosques, the Roman Catholic cathedral of St Philippe, the church of the Holy Trinity (Church of England), and the Bibliotheque Nationale d'Alger--a Turkish palace built in 1799-1800. The kasbah was begun in 1516 on the site of an older building, and served as the palace of the deys until the French conquest. A road has been cut through the centre of the building, the mosque turned into barracks, and the hall of audience allowed to fall into ruin. There still remain a minaret and some marble arches and columns. Traces exist of the vaults in which were stored the treasures of the dey. The Grand Mosque (Jamaa-el-Kebir) is traditionally said to be the oldest mosque in Algiers. The pulpit (mimbar) bears an inscription showing that the building existed in 1018. The minaret was built by Abu Tachfin, sultan of Tlemcen, in 1324. The interior of the mosque is square and is divided into aisles by columns joined by Moorish arches. The principal facade, in the rue de la Marine, consists of a row of white marble columns supporting an arcade. The New Mosque (Jamaa-el-Jedid), dating from the 17th century, is in the form of a Greek cross, surmounted by a large white cupola, with four small cupolas at the corners. The minaret is 90 ft. high. The interior resembles that of the Grand Mosque. The church of the Holy Trinity (built in 1870) stands at the southern end of the rue d'Isly near the site of the demolished Fort Bab Azoun. The interior is richly decorated with various coloured marbles. Many of these marbles contain memorial inscriptions relating to the English residents (voluntary and involuntary) of Algiers from the time of John Tipton, British consul in 1580. One tablet records that in 1631 two Algerine pirate crews landed in Ireland, sacked Baltimore, and carried off its inhabitants to slavery; another recalls the romantic escape of Ida M`Donnell, daughter of Admiral Ulric, consul- general of Denmark, and wife of the British consul. When Lord Exmouth was about to bombard the city in 1816, the British consul was thrown into prison and loaded with chains. Mrs. M`Donnell--who was but sixteen--escaped to the British fleet disguised as a midshipman, carrying a basket of vegetables in which her baby was hidden. (Mrs. M`Donnell subsequently married the duc de Talleyrand-Perigord and died at Florence in 1880). Among later residents commemorated is Edward Lloyd, who was the first person to show the value of esparto grass for the manufacture of paper, and thus started an industry which is one of the most important in Algeria.

The cathedral of St Philippe, built on the site of a mosque, is in the place Malakoff, next to the governor-general's palace. In its construction an attempt has been made to produce a building suitable for Christian worship whilst the architecture is Moorish in style. The principal entrance, reached by a flight of 23 steps, is ornamented with a portico supported by four black-veined marble columns. The roof of the nave is of Moorish plaster work. It rests on a series of arcades supported by white marble columns. Several of these columns belonged to the former mosque. In one of the chapels is a tomb containing the bones of San Geronimo. The finding of the remains of the saint in 1853 afforded striking confirmation of an incident recorded by a Spanish Benedictine named Haedo, who published a topography of Algeria in 1612. Haedo sets forth that a young Arab who had embraced Christianity and had been baptized with the name of Geronimo was captured by a Moorish corsair in 1569 and taken to Algiers. The Arabs endeavoured, to induce Geronimo to renounce Christianity, but as he steadfastly refused to do so he was condemned to death. Bound hand and foot he was thrown alive into a mould in which a block of concrete was about to be made. The block containing his body was built into an angle of the Fort of the Twenty-four Hours, then under construction. In 1853 the Fort of the Twenty-four Hours was demolished, and in the angle specified by Haedo the skeleton of Geronimo was found. The bones were interred at St Phihppe. Into the mould left by the saint's body liquid plaster of Paris was run, and a perfect model obtained, showing the features of the youth, the cords which bound him, and even the texture of his clothing. This model is now in the museum at Mustapha (see below).

Algiers possesses a college with schools of law, medicine, science and letters. The college buildings are large and handsome. There is also a lycee in which the instruction is similar to that given in France, and in which Christians, Jews and Mahommedans are educated together. The museum (a state institution), formerly housed in the same building as the library, was transferred in 1897 to a new building in the suburb of Mustapha Superieur. In the museum are some of the ancient sculptures and mosaics discovered in Algeria, together with medals and Algerian money. New buildings, to contain specimens of Moslem art, were added in 1903.

The port of Algiers is sheltered from all winds. There are two harbours, both artificial--the old or northern harbour and the southern or Agha harbour. The northern harbour covers an area of 235 acres. The depth at the entrance is 72 to 108 ft., and in port from 36 to 66 ft. Two government dry docks are available for merchant vessels. The quays cover 18,000 sq. yds. There are three jetties, north, east and south. Within this harbour is the small harbour of the deys, now transformed into a wet dock. An opening in the south jetty affords an entrance into Agha harbour, constructed in Agha Bay. This harbour is formed by the projection of a mole, 2500 ft. in length, from the eastern jetty of the old harbour. It provides extensive quayage with a minimum depth of water of 28 ft. Agha harbour has also an independent entrance on its southern side. Algiers is the chief coaling station in the Mediterranean, having become so largely at the expense of Gibraltar. In other respects the trade resembles that of other Algerian ports. (For trade statistics see ALGERIA.) The inner harbour was begun in 1518 by Khair-ed- Din (see History, below), who, to accommodate his pirate vessels, caused the island on which was Fort Penon to be connected with the mainland by a mole. The lighthouse which occupies the site of Fort Penon was built in 1544. Work on the northern harbour was begun in 1836, on the southern in 1904. Algiers maintains communication with Marseilles by a quick service of steamers, which run the 497 miles across the Mediterranean in twenty-eight to thirty hours. The journey between Algiers and Paris, from which it is distant 1031 miles, is accomplished in about forty-five hours.

Algiers was a walled city from the time of the deys until the close of the 19th century. The French, after their occupation of the city (1830), built a rampart, parapet and ditch, with two terminal forts, Bab Azoun to the south and Bab-el-Oued to the north. The forts and part of the ramparts were demolished at the beginning of the 20th century, when a line of forts occupying the heights of Bu Zarea (at an elevation of 1300 ft. above the sea) took their place.

Owing to the mildness of its climate Algiers has become a favourite resort for those seeking to escape the rigours of a European winter. The city is well supplied with water and its sanitary state is good. The mistral of the Riviera is entirely absent from Algiers, but in summer the city occasionally suffers from the sirocco or desert wind. The environs of Algiers are noted for their beauty and healthiness. Of the suburbs the most picturesque is Mustapha Superieur, about 2 m. from the centre of the city on the slopes of the hills to the south. Here are the summer palace of the governor-general, many fine Moorish and French villas and luxurious hotels, all surrounded by beautiful gardens. A numerous British colony resides at Mustapha, where there is an English club. Mustapha Inferieur is built on the lower slopes of the hills. Farther to the south is the large Jardin d'Essai, containing five avenues of palms, planes, bamboos and magnolias. Notre-Dame d'Afrique, a church built (1858- 1872) in a mixture of the Roman and Byzantine styles, is conspicuously situated, overlooking the sea, on the shoulder of the Bu Zarea hills, 2 m. to the north of the city. Above the altar is a statue of the Virgin depicted as a black woman. The church also contains a solid silver statue of the archangel Michael, belonging to the confraternity of Neapolitan fishermen. Beyond Notre-Dame d'Afrique is the beautiful Valley of the Consuls, very little changed since the time of the deys. (The valley was in those days the favourite residence of the consuls.) At the Petit Seminaire, on the site of the old French consulate, Cardinal Lavigerie died (1892).

In 1906 the population of the commune of Algiers was 154,049; the population municipale, which excludes the garrison, prisoners, &c., was 145,280. Of this total 138,240 were living in the city proper or in Mustapha. Of the inhabitants 105,908 were Europeans. French residents numbered 50,996, naturalized Frenchmen 23,305, Spaniards 12,354, Italians 7368, Maltese 865, and other Europeans (chiefly British and Germans) 1652, besides 12,490 Jews. The remainder of the population--all Mahommedans--are Moors, Arabs, Berbers, Negroes, with a few Turks. The vast majority of the Europeans are Roman Catholics. Most of the naturalized French citizens are of Spanish or Italian origin.

History.--In Roman times a small town called Icosium existed on what is now the marine quarter of the city. The rue de la Marine follows the lines of a Roman street. Roman cemeteries existed near the rues Bab-el-Oued and Bab Azoun. Bishops of Icosium--which was created a Latin city by Vespasian --are mentioned as late as the 5th century. The present city was founded in 944 by Bulukkin b. Zeiri, the founder of, the Zeirid-Sanhaja dynasty, which was overthrown by Roger II. of Sicily in 1148 (see FATIMITES.) The Zeirids had before that date lost Algiers, which in 1159 was occupied by the Almohades, and in the 13th century came under the dominion of the Abd-el- Wahid, sultans of Tlemcen. Numinally part of the sultanate of Tlemcen, Algiers had a large measure of independence under amirs of its own, Oran being the chief seaport of the Abd-el- Nahid. The islet in front of the harbour, subsequently known as the Penon, had been occupied by the Spaniards as early as 1302. Thereafter a considerable trade grew up between Algiers and Spain. Algiers, however, continued of comparatively little importance until after the expulsion from Spain of the Moors, many of whom sought an asylum in the city. In 1510, following their occupation of Oran and other towns on the coast of Africa, the Spaniards fortified the Penon. In 1516 the amir of Algiers, Selim b. Teumi, invited the brothers Arouj and Khair-ed-Din (Barbarossa) to expel the Spaniards. Arouj came to Algiers, caused Selim to be assassinated, and seized the town. Khair- ed-Din, succeeding Arouj, drove the Spaniards from the Penon (1550) and was the founder of the pashalik, afterwards deylik, of Algeria. Algiers from this time became the chief seat of the Barbary pirates. In October 1541 the emperor Charles V. sought to capture the city, but a storm destroyed a great number of his ships, and his army of some 30,000, chiefly Spaniards, was defeated by the Algerians under their pasha, Hassan. Repeated attempts were made by various European nations to subdue the pirates, and in 1816 the city was bombarded by a British squadron under Lord Exmouth, assisted by Dutch men-of-war, and the corsair fleet burned. The piracy of the Algerians was renewed and continued until 1830. On the 4th of July in that year a French army under General de Bourmont attacked the city, which capitulated on the following day (see ALGERIA, History.)

ALGOA BAY, a wide, shallow bay of South Africa, 436 m. E. from the Cape of Good Hope, bounded W. by Cape Recife, E. by Cape Padrone. St Croix Island in the bay is in 33 deg. 47' S. 25 deg. 46' E. On this island Bartholomew Diaz made his second landing in South Africa some time after the 3rd of February 1488, and from the cross which he is thought to have erected on it the island gets its name. Algoa Bay was the first landing-place of the British emigrants to the eastern province of Cape Colony in 1820. At a spot 6 m. N.E. of Cape Recife these emigrants founded a town, Port Elizabeth (q.v.), its harbour being sheltered from all winds save the S.E. By seafarers ``Algoa Bay'' is used as synonymous with Port Elizabeth.

ALGOL, the Arabic name (signifying ``the Demon'') of b Persei, a star of the second magnitude, noticed by G. Montanari in 1669 to fluctuate in brightness. John Goodricke established in 1782 the periodicity of its change in about 2d 21h and suggested their cause in recurring eclipses by a large dark satellite. Their intermittent character prompted the supposition. The light of Algol remains constant during close upon 56 hours; then declines in 6 1/2 hours (approximately) to nearly one-fourth its normal amount, and is restored by sensibly the same gradations. The amplitude of the phase is 1.1 magnitude; and the absence of any stationary interval at minimum proves the eclipse to be partial, not annular. Its conditions were investigated from photometric data, by Professor E. C. Pickering in 1880;1 and their realization was finally demonstrated by Dr H. C. Vogel's spectroscopic measures in 1889.2 Previously to each obscuration, the star was found to be moving rapidly away from the earth; its velocity then diminished to zero pari passu with the loss of light, and reversed its direction during the process of recovery. Algol, in fact, travels at the rate of 26.3 miles a second round the centre of gravity of the system which it forms with an invisible companion, while the two together approach the sun with an unvarying speed of 2.3 miles per second. The elements of this disparate pair, calculated by Dr Vogel on the somewhat precarious assumption that its dark and bright members are of equal mean density, are as follows:--

Diameter of Algol . . . . 1,061,000 English miles. '' Satellite . . . 834,300 '' '' Distance from centre to centre. 3,230,000 '' '' Mass of Algol . . . . . 4/9 solar mass. '' Satellite . . . . 2/9 '' '' Mean density . . . . . about 1/4 solar.

The plane of the joint orbit, in which no deviation from circularity has yet been detected, nearly coincides with the line of sight. The period of Algol, as measured by its eclipses, is subject to complex irregularities. It shortened fitfully by eight seconds between 1790 and 1879; soon afterwards, restoration set in, and its exact length in 1903 was 2d 20h 48m 56s, being only two seconds short of its original value. By an exhaustive discussion, Dr S. Chandler ascertained in 1888 the compensatory nature of these disturbances;3 and he afterwards found the most important among several which probably conspire to produce the observed effects, to be comprised in a period of 15,000 light-cycles, equivalent to 118 years.4 An explanatory hypothesis, propounded by him in 1892,5 is still on its trial. The system of Algol, according to this view, is triple; it includes a large, obscure primary, round which the eclipsing pair revolves in an orbit somewhat smaller than that of Uranus, very slightly elliptical, and inclined 20 deg. to the line of sight, the periodic time being 118 years. The alternate delay and acceleration of the eclipses are then merely apparent; they represent the changes in the length of the light-journey as the stars perform their wide circuit. If these suppositions have a basis of reality, the proper motion of Algol should be disturbed by a small, but measurable undulation, corresponding to the projection of its orbit upon the sky; and although certainty on the point cannot be attained for some years to come, Lewis Boss regarded the evidence available in 1895 as tending to confirm Dr Chandler's theory.6

A rival interpretation of the phenomena it dealt with was put forward by F. Tisserand in 1895.7 It involved the action of no third mass, but depended solely upon the progression of the line of apsides in a moderately elliptical orbit due to the spheroidal shape of the globes traversing it. Inequalities of the required sort in the returns of the eclipses would ensue; moreover, their duration should concomitantly vary with the varying distance from periastron at the times of their occurrence. It is a moot question whether changes of the latter kind actually occur. When they are proved to do so, Tisserand's hypothesis will hold the field.

Algol gives a helium-spectrum which undergoes no alteration at minimum. Hence the light from the marginal and central portions of the disc is identical in quality, and the limb can be little, if at all, darkened by the ``smoke-veil'' absorption conspicuous in the sun. The rays of this star spend close upon a century in travelling hither. Dr Chase's measures with the Yale heliometer indicated for it, in 1894, a parallax of about 0'' .035;8 and it must, accordingly, be of nearly four times the total brightness of Sirius, while its aerial lustre exceeds seventy- fold that of the solar photosphere. Variables of the Algol class are rendered difficult to discover by the incidental character of their fluctuations. At the end of 1905, however, about 37 had been certainly recognized, besides some outlying cases of indeterminate type, in which continuous occultations by two bright stars, revolving in virtual contact, are doubtfully supposed to be in progress. (A. M. C.)

1 Proceedings Amer. Acad. vol. xvi. p. 27. 2 Astr. Nach. No. 2947. 3 Astr. Journal, No. 165. 4 Ibid. No. 509. 5 Ibid. Nos. 255-256. 6 Ibid. No. 343. 7 Comptes Rendus, t. cxx. p 125. 8 Astr. Jour. No. 318. ALGONQUIN, or ALGONKIN (a word formerly regarded as a French contraction of Algomequin, ``those on the other side'' of the river, viz. the St Lawrence, hut now believed to be from the Micmac algoomaking--``at the place of spearing fish''), a collective term for a number of tribes of North American Indians dwelling in the valley of the Ottawa river and around the northern tributaries of the St Lawrence. The Algonquins allied themselves with the French against the Iroquois. Many were driven west by the latter and later became known as Ottawa. The French missionaries at work among the Algonquins early in the 17th century found their language to be the key to the many Indian dialects now included by philologists under the general term ``Algonquian stock.'' The chief tribes included in this stock were the Algonquin, Malecite, Micmac, Nascapi, Pennacook, Fox, Kickapoo, Delaware, Cheyenne, Conoy, Cree, Mohican, Massachuset, Menominee, Miami, Misisaga, Mohegan, Nanticoke, Narraganset, Nipmuc, Ojibway, Ottawa, Pequot, Potawatami, Sac, Shawnee and Wampanoag. The Indians of Algonquian stock number between 80,000 and 90,000, of whom rather more than half are in the United States, the rest being in Canada. Of the Algonquins proper there remain about 1500 settled in the provinces of Quebec and Ontario.

For details see Handbook of American Indians, ed. F. W. Hodge, Washington, 1907.

ALGUAZIL, a Spanish title often to be met in stories and plays, derived from the Arabic ``visir'' and the article, `` al.'' The alguazil among the early Spaniards was a judge, and sometimes the governor of a town or fortress. In later times he has gradually sunk down to the rank of an officer of the court, who is trusted with the service of writs and certain police duties, but he is still of higher rank than the mere corchete or catch-poll. The title has also been given to inspectors of weights and measures in market-places, and similar officials.

ALGUM, or ALMUG TREE. The Hebrew words Algummim or Almuggim are translated Algum or Almug trees in the authorized version of the Bible (see 1 Kings x. 11, 12; 2 Chron. ii. 8, and ix. 10, 11); almug is an erroneous form (see Max Muller, Science of Language, vol. i.). The wood of the tree was very precious, and was brought from Ophir (probably some part of India), along with gold and precious stones, by Hiram, and was used in the formation of pillars for the temple at Jerusalem, and for the king's house; also for the inlaying of stairs, as well as for harps and psalteries. It is probably the red sanders or red sandal-wood of India ( Pterocarpus santalinus.) This tree belongs to the natural order Leguminosae, sub-order Papilionaceae. The wood is hard, heavy, close-grained and of a fine red colour. It is different from the white fragrant sandal-wood, which is the produce of Santalum album, a tree belonging to a distinct natural order Santalaceae.

ALHAMA DE GRANADA, a town of southern Spain, in the province of Granada, 24 m. S.W. of Granada. Pop. (1900) 7679. Alhama is finely situated on a ledge of rock which overlooks a deep gorge traversed by the river Marchan or Alhama; while the rugged peaks of the Sierra de Alhamarise behind it to a height of 6800 ft. The town is largely modern; for over one thousand of its picturesque old Moorish houses, which formerly rose in terraces up the mountain side, were destroyed, together with five churches, the hospital, the theatre, the prison, and 800 of the inhabitants, in an earthquake which took place in 1884. Subscriptions were received from all parts of Spain, and the present town was built at a little distance from its predecessor. Few vestiges of antiquity survived, except the baths from which Alhama (in Arabic ``the Bath'') derives its name. These are situated near the river, and appear to have been used continuously since Roman times (c. 19 B.C.- A.D. 409) . The temperature of the hot sulphurous springs is about 112 deg. F.; and, as the waters are considered beneficial in cases of rheumatism and dyspepsia, many visitors come to Alhama in spring and autumn, attracted also by the fine scenery of the district. In the 15th century Alhama, and the neighbouring fortress of Loja (q.v.), were generally regarded as the keys of the kingdom of Granada, and their capture went far to insure the overthrow of the Moorish power. Alhama was taken by the Spanish marquis of Cadiz in 1482; and its fall is celebrated in an ancient ballad, Ay de mi, Alhama, which Byron translated into English.

ALHAMBRA, THE, an ancient palace and fortress of the Moorish monarchs of Granada, in southern Spain, occupying a hilly terrace on the south-eastern border of the city of Granada. This terrace or plateau, which measures about 2430 ft. in length by 674 ft. at its greatest width, extends from W.N.W. to E.S.E., and covers an area of about 35 acres. It is enclosed by a strongly fortified wall, which is flanked by thirteen towers. The river Darro, which foams through a deep ravine on the north, divides the plateau from the Albaicin district of Granada; the Assabica valley, containing the Alhambra Park, on the west and south, and beyond this valley the almost parallel ridge of Monte Mauror, separate it from the Antequeruela district.

The name Alhambra, signifying in Arabic ``the red,'' is probably derived from the colour of the sun-dried tapia, or bricks made of fine gravel and clay, of which the outer walls are built. Some authorities, however, hold that it commemorates the red flare of the torches by whose light the work of construction was carried on nightly for many years; others associate it with the name of the founder, Mahomet Ibn Al Ahmar; and others derive it from the Arabic Dar al Amra, ``House of the Master.'' (For an account of the period to which the Alhambra belongs, see GRANADA (city) .) The palace was built chiefly between 1248 and 1354, in the reigns of Al Ahmar and his successors; but even the names of the principal artists employed are either unknown or doubtful. The splendid decorations of the interior are ascribed to Yusef I., who died in 1354. Immediately after the expulsion of the Moors in 1492, their conquerors began, by successive acts of vandalism, to spoil the marvellous beauty of the Alhambra. The open work was filled up with whitewash, the painting and gilding effaced, the furniture soiled, torn or removed. Charles V. (1516-1556) rebuilt portions in the modern style of the period, and destroyed the greater part of the winter palace to make room for a modern structure which has never been completed. Philip V. (1700-1746) Italianised the rooms, and completed the degradation by running up partitions which blocked up whole apartments, gems of taste and patient ingenuity. In subsequent Centuries the carelessness of the Spanish authorities permitted this masterpiece of Moorish art to be still further defaced; and in 1812 some of the towers were blown up by the French under Count Sebastiani, while the whole buildings narrowly escaped the same fate. In

Plan of the Alhambra Scale of Yards 1. Court of Myrtles 2. Hall of Ambassadors 3. Court of Lions 4. Hall of the Abencerrages 5. Room of the Two Sisters 6. Modern Entrance 7. Court of the Vestibule 8. Baths 9. Court of the Council Chamber 10. Queens Robing Room

from Baedeker's Spain & Portugal, by permission of Karl Baedeker Emery Walker SC.

1821 an earthquake caused further damage. The work of restoration undertaken in 1828 by the architect Jose Contreras was endowed in 1830 by Ferdinand VII.; and after the death of Contreras in 1847, it was continued with fair success by his son Rafael (d. 1890), and his grandson Mariano.

The situation of the Alhambra is one of rare natural beauty; the plateau commands a wide view of the city and plain of Granada, towards the west and north, and of the heights of the Sierra Nevada, towards the east and south. Moorish poets describe it as ``a pearl set in emeralds,'' in allusion to the brilliant colour of its buildings, and the luxuriant woods round them. The park (Alameda de la Alhambra), which in spring is overgrown with wild-flowers and grass, was planted by the Moors with roses, oranges and myrtles; its most characteristic feature, however, is the dense wood of English elms brought hither in 1812 by the duke of Wellington. The park is celebrated for the multitude of its nightingales, and is usually filled with the sound of running water from several fountains and cascades. These are supplied through a conduit 5 m. long, which is connected with the Darro at the monastery of Jesus del Valle, above Granada.

The Moorish portion of the Alhambra resembles many medieval Christian strongholds in its threefold arrangement as a castle, a palace and a residential annexe for subordinates. The Alcazaba or citadel, its oldest part, is built on the isolated and precipitous foreland which terminates the plateau on the north-west. Only its massive outer walls, towers and ramparts are left. On its watch-tower, the Torre de la Vela, 85 ft. high, the flag of Ferdinand and Isabella was first raised, in token of the Spanish conquest of Granada, on the 2nd of January 1492. A turret containing a huge bell was added in the 18th century, and restored after being injured by lightning in 1881. Beyond the Alcazaba is the palace of the Moorish kings, or Alhambra properly so-called; and beyond this, again, is the Alhambra Alta (Upper Alhambra), originally tenanted by officials and courtiers.

In spite of the long neglect, wilful vandalism and ill-judged restoration which the Alhambra has endured, it remains the most perfect example of Moorish art in its final European development, --freed from the direct Byzantine influences which can be traced in the cathedral of Cordova, more elaborate and fantastic than the Giralda at Seville. The majority of the palace buildings are, in ground-plan, quadrangular, with all the rooms opening on to a central court; and the whole reached its present size simply by the gradual addition of new quadrangles, designed on the same principle, though varying in dimensions, and connected with each other by smaller rooms and passages. In every case the exterior is left plain and austere, as if the architect intended thus to heighten by contrast the splendour of the interior. Within, the palace is unsurpassed for the exquisite detail of its marble pillars and arches, its fretted ceilings and the veil-like transparency of its filigree work in stucco. Sun and wind are freely admitted, and the whole effect is one of the most airy lightness and grace. Blue, red, and a golden yellow, all somewhat faded through lapse of time and exposure, are the colours chiefly employed. The decoration consists, as a rule, of stiff, conventional foliage, Arabic inscriptions, and geometrical patterns wrought into arabesques of almost incredible intricacy and ingenuity. Painted tiles are largely used as panelling for the walls.

Access from the city to the Alhambra Park is afforded by the Puerta de las Granadas (Gate of Pomegranates), a massive triumphal arch dating from the 15th century. A steep ascent leads past the Pillar of Charles V., a fountain erected in 1554, to the main entrance of the Alhambra. This is the Puerta Judiciaria (Gate of Judgment), a massive horseshoe archway, surmounted by a square tower, and used by the Moors as an informal court of justice. A hand, with fingers outstretched as a talisman against the evil eye, is carved above this gate on the exterior; a key, the symbol of authority, occupies the corresponding place on the interior. A narrow passage leads inward to the Plaza de los Aljibes (Place of the Cisterns), a broad open space which divides the Alcazaba from the Moorish palace. To the left of the passage rises the Torre del Vino (Wine Tower), built in 1345, and used in the 16th century as a cellar. On the right is the palace of Charles V., a cold-looking but majestic Renaissance building, out of harmony with its surroundings, which it tends somewhat to dwarf by its superior size. Its construction, begun in 1526, was abandoned about 1650.

The present entrance to the Palacio Arabe, or Casa Real (Moorish palace), is by a small door from which a corridor conducts to the Patio de los Arrayanes (Court of the Myrtles), also called the Patio de la Alberca (Court of the Blessing or Court of the Pond), from the Moorish birka, ``pond,'' or berka, ``blessing.'' This court is 140 ft. long by 74 ft. broad; and in the centre there is a large pond set in the marble pavement, full of goldfish, and with myrtles growing along its sides. There are galleries on the north and south sides; that on the south 27 ft. high, and supported by a marble colonnade. Underneath it, to the right, was the principal entrance, and over it are three elegant windows with arches and miniature pillars. From this court the walls of the Torre de Comares are seen rising over the roof to the north, and reflected in the pond.

The Sala de los Ambajadores (Hall of the Ambassadors) is the largest in the Alhambra, and occupies all the Torre de Comares. It is a square room, the sides being 37 ft. in length, while the centre of the dome is 75 ft. high. This was the grand reception room, and the throne of the sultan was placed opposite the entrance. The tiles are nearly 4 ft. high all round, and the colours vary at intervals. Over them is a series of oval medallions with inscriptions, interwoven with flowers and leaves. There are nine windows, three on each facade, and the ceiling is admirably diversified with inlaid-work of white, blue and gold, in the shape of circles, crowns and stars--a kind of imitation of the vault of heaven. The walls are covered with varied stucco-work of most delicate pattern, surrounding many ancient escutcheons.

The celebrated Patio de los Leones (Court of the Lions) is an oblong court, 116 ft. in length by 66 ft. in breadth, surrounded by a low gallery supported on 124 white marble columns. A pavilion projects into the court at each extremity, with filigree walls and light domed roof, elaborately ornamented. The square is paved with coloured tiles, and the colonnade with white marble; while the walls are covered 5 ft. up from the ground with blue and yellow tiles, with a border above and below enamelled blue and gold. The columns supporting the roof and gallery are irregularly placed, with a view to artistic effect; and the general form of the piers, arches and pillars is most graceful. They are adorned by varieties of foliage, &c.; about each arch there is a large square of arabesques; and over the pillars is another square of exquisite filigree work. In the centre of the court is the celebrated Fountain of Lions, a magnificent alabaster basin supported by the figures of twelve lions in white marble, not designed with sculptural accuracy, but as emblems of strength and courage.

The Sala de los Abencerrajes (Hall of the Abencerrages) derives its name from a legend according to which Boabdil, the last king of Granada, having invited the chiefs of that illustrious line to a banquet, massacred them here. This room is a perfect square, with a lofty dome and trellised windows at its base. The roof is exquisitely decorated in blue, brown, red and gold, and the columns supporting it spring out into the arch form in a remarkably beautiful manner. Opposite to this hall is the Sala de las dos Hermanas (Hall of the two Sisters), so-called from two very beautiful white marble slabs laid as part of the pavement. These slabs measure 15 ft. by 7 1/2 ft., and are without flaw or stain. There is a fountain in the middle of this hall, and the roof--a dome honeycombed with tiny cells, all different, and said to number 5000--is a magnificent example of the so-called ``stalactite vaulting'' of the Moors.

Among the other wonders of the Alhambra are the Sala de la Justicia (Hall of Justice), the Patio del Mexuar (Court of the Council Chamber), the Patio de Daraxa (Court of the Vestibule), and the Peinador de la Reina (Queen's Robing Room), in which are to be seen the same delicate and beautiful architecture, the same costly and elegant decorations. The palace and the Upper Alhambra also contain baths, ranges of bedrooms and summer- rooms, a whispering gallery and labyrinth, and vaulted sepulchres.

The original furniture of the palace is represented by the celebrated vase of the Alhambra, a splendid specimen of Moorish ceramic art, dating from 1320, and belonging to the first period of Moorish porcelain. It is 4 ft. 3 in. high; the ground is white, and the enamelling is blue, white and gold.

Of the outlying buildings in connexion with the Alhambra. the foremost in interest is the Palacio de Generalife or Gineralife (the Moorish Jennat al Arif, ``Garden of Arif,'' or ``Garden of the Architect''). This villa probably dates from the end of the 13th century, but has been several times restored. Its gardens, however, with their clipped hedges, grottos, fountains, and cypress avenues, are said to retain their original Moorish character. The Villa de los Martires (Martyrs' Villa), on the summit of Monte Mauror, commemorates by its name the Christian slaves who were employed to build the Alhambra, and confined here in subterranean cells. The Torres Bermejas (Vermilion Towers), also on Monte Mauror, are a well-preserved Moorish fortification, with underground cisterns, stables, and accommodation for a garrison of 200 men. Several Roman tombs were discovered in 1829 and 1857 at the base of Monte Mauror.

See Plans, Elevations, Sections and Details of the Alhambra; from drawings taken on the spot by J. Goury and Owen Jones; with a complete translation of the Arabic inscriptions and a historical notice of the Kings of Granada, by P. de Gayangos. These two magnificent folios, though first published in London between 1842 and 1845, give the best pictorial representation of the Alhambra. See also Rafael Contreras, La Alhanabra, El Alcazar, y la gran Mezquita de Occidente Madrid, 1885); The Alhambra, by Washington Irving, was written in 1832, and rewritten in 1857, when it had already become widely celebrated for its picturesque and humorous descriptions. A well-Illustrated edition was published in London in 1896.

ALHAZEN (ABU ALI AL-HASAN IBN ALHASAN), Arabian mathematician of the 11th century, was born at Basra and died at Cairo in 1038. He is to be distinguished from another Alhazen who translated Ptolemy's Almagest in the 10th century. Having boasted that he could construct a machine for regulating the inundations of the Nile, he was summoned to Egypt by the caliph Hakim; but, aware of the impracticability of his scheme, and fearing the caliph's anger, he feigned madness until Hakim's death in 1021. Alhazen was, nevertheless, a diligent and successful student, being the first great discoverer in optics after the time of Ptolemy. According to Giovanni Battista della Porta, he first explained the apparent increase of heavenly bodies near the horizon, although Bacon gives the credit of this discovery to Ptolemy. He taught, previous to the Polish physicist Witelo, that vision does not result from the emission of rays from the eye, and wrote also on the refraction of light, especially on atmospheric refraction, showing, e.g. the cause of morning and evening twilight. He solved the problem of finding the point in a convex mirror at which a ray coming from one given point shall be reflected to another given point. His treatise on optics was translated into Latin by Witelo (1270), and afterwards published by F. Risner in 1572, with the title Oticae thesaurus Alhazeni libri VII., cum ejusdem libro de crepusculis et nubium ascensionibus. This work enjoyed a great reputation during the middle ages. Works on geometrical subjects were found in the Bibliotheque nationale de Paris in 1834 by E. A. Sedillot; other manuscripts are preserved in the Bodleian library at Oxford and in the library of Leiden.

See Casiri, Bibl. Arab. Hisp. Escur.; J. E. Montucla, Histoire des mathemaltiques (1758); and E. A. Sedillot, Materiaux pour l'histoire des sciences mathematiques.

ALI, in full, 'ALI BEN ABU TALIB (c. 600-661), the fourth of the caliphs or successors of Mahomet, was born at Mecca about the year A.D. 600. His father, Abu Talib, was an uncle of the prophet, and Ali himself was adopted by Mahomet and educated under his care. As a mere boy he distinguished himself by being one of the first to declare his adhesion to the cause of Mahomet, who some years afterwards gave him his daughter Fatima in marriage. Ali proved himself to be a brave and faithful soldier, and when Mahomet died without male issue, a few emigrants thought him to have the best claim to succeed him. Abu Bekr, Omar and Othman, however, occupied this position before him, and it was not until 656, after the murder of Othman, that he assumed the title of caliph. The fact that he took no steps to prevent this murder is, perhaps, the only real blot upon his character. Almost the first act of his reign was the suppression of a rebellion under Talha and Zobair, who were instigated by Ayesha, Mahomet's widow, a bitter enemy of Ali, and one of the chief hindrances to his advancement to the caliphate. The rebel army was defeated at the ``Battle of the Camel,'' near Bassorah (Basra), the two generals being killed, and Ayesha taken prisoner. Ali soon afterwards made Kufa his capital. His next care was to get rid of the opposition of Moawiya, who had established himself in Syria at the head of a numerous army. A prolonged battle took place in July 657 in the plain of Siffin (Suffein), near the Euphrates; the fighting was at first, it is said, in favour of Ali, when suddenly a number of the enemy, fixing copies of the Koran to the points of their spears, exclaimed that ``the matter ought to be settled by reference to this book, which forbids Moslems to shed each other's blood.'' The superstitious soldiers of Ali refused to fight any longer, and demanded that the issue be referred to arbitration (see further CALIPHATE, section B. 1). Abu Musa was appointed umpire on the part of Ali, and `Amr-ibn-el-Ass, a veteran diplomatist, on the part of Moawiya. It is said that `Amr persuaded Abu Musa that it would be for the advantage of Islam that neither candidate should reign, and asked him to give his decision first. Abu Musa having proclaimed that he deposed both Ali and Moawiya, `Amr declared that he also deposed Ali, and announced further that he invested Moawiya with the caliphate. This treacherous decision (but see CALIPHATE, ib.) greatly injured the cause of Ali, which was still further weakened by the loss of Egypt. After much indecisive fighting, Ali found his position so unsatisfactory that according to some historians he made an agreement with Moawiya by which each retained his own dominions unmolested. It chanced, however--according to a legend, the details of which are quite uncertain--that three of the fanatic sect of the Kharijites had made an agreement to assassinate Ali, Moawiya and `Amr, as the authors of disastrous feuds among the faithful. The only victim of this plot was Ali, who died at Kufa in 661, of the wound inflicted by a poisoned weapon. A splendid mosque called Meshed Ali was afterwards erected near the city, but the place of his burial is unknown. He had eight wives after Fatima's death, and in all, it is said, thirty-three children, one of whom, Hassan, a son of Fatima, succeeded him in the caliphate. His descendants by Fatima are known as the Fatimites (q.v.; see also EGYPT: History, Mahommedan period). The question of Ali's right to succeed to the caliphate is an article of faith which divided the Mahommedan world into two great sects, the Sunnites and the Shiites, the former denying, and the latter affirming, his right. The Turks, consequently, hold his memory in abhorrence; whereas the Persians, who are generally Shi`as, venerate him as second only to the prophet, call him the ``Lion of God'' (Sher-i-Khuda), and celebrate the anniversary of his martyrdom. Ali is described as a bold, noble and generous man, ``the last and worthiest of the primitive Moslems, who imbibed his religious enthusiasm from companionship with the prophet himself, and who followed to the last the simplicity of his example.'' It is maintained, on the other hand, that his motives were throughout those of ambition rather than piety, and that, apart from the tragedy of his death, he would have been an insignificant figure in history. (See further CALIPHATE.)

In the eyes of the later Moslems he was remarkable for learning and wisdom, and there are extant collections (almost all certainly spurious) of proverbs and verses which bear his name: the Sentences of Ali (Eng. trans., William Yule, Edinburgh, 1832); H. L. Fleischer, Alis hundert Spruche (Leipz. 1837); the Divan, by G. Kuypert (Leiden, 1745, and at Bulak, 1835); C. Brockelmann, Gesch. d. arabisch. Lit. (vol. i., Weimar, 1899).

ALI, known as ALI BEY (1766-1818), the assumed name of DOMINGO BADIA Y LEBLICH, a Spanish traveller, born in 1766. After receiving a liberal education he devoted particular attention to the Arabic language, and made a special study of the manners and customs of the East. Pretending to be a descendant of the Abbasids, Badia in 1803 set out on his travels. Under the name of Ali Bey el Abbassi, and in Mussulman costume, he visited Morocco, Tripoli, Egypt, Arabia and Syria, and was received as a person of high rank wherever he appeared. He made the pilgrimage to Mecca, at that time in the possession of the Wahabites. On his return to Spain in 1807 he declared himself a Bonapartist, and was made intendant first of Segovia and afterwards of Cordova. When the French were driven from Spain, Badia was compelled to take refuge in France, and there in 1814, published an account of his travels under the title of Voyage d'Aii Bey en Asie et en Afrique, &c. A few years later he set out again for Syria, under the assumed name of Ali Othman, and, it is said, accredited as a political agent by the French government. He reached Aleppo, and there died on the 30th of August 1818, not without suspicion of having been poisoned.

An account of his Eastern adventures was published in London in 1816, in two volumes, entitled Travels in Morocco, Tripoli, Cyprus, Egypt, Arabia, Syria and Turkey, between the years 1803 and 1807.

ALI, known as ALI PASHA (1741-1822),Turkish pasha of Iannina, surnamed Arslan, ``the Lion,'' was born at Tepeleni, a village in Albania at the foot of the Klissura mountains. He was one of the Toske tribe, and his ancestors had for some time held the hereditary office of bey of Tepeleni. His father, a man of mild and peaceful disposition, was killed when Ali was fourteen years old by neighbouring chiefs who seized his territories. His mother Khamko, a woman of extraordinary character, thereupon herself formed and led a brigand band, and studied to inspire the boy with her own fierce and indomitable temper, with a view to revenge and the recovery of the lost property. In this wild school Ali proved an apt pupil. A hundred tales, for the most part probably mythical, are told of his powers and cunning during the years he spent among the mountains as a brigand leader. At last, by a picturesque stratagem, he gained possession of Tepeleni and took vengeance on his enemies. To secure himself from rivals in his own family, he is said to have murdered his brother and imprisoned his mother on a charge of attempting to poison him. With a view to establishing his authority he now made overtures to the Porte and was commissioned to chastise the rebellious pasha of Scutari, whom he defeated and killed. He also, on pretext of his disloyalty, put to death Selim, pasha of Delvinon. Ali was now confirmed in the possession of all his father's territory and was also appointed lieutenant to the derwend-pasha of Rumelia, whose duty it was to suppress brigandage and highway robbery. This gave him an opportunity for amassing wealth by sharing the booty of the robbers in return for leaving them alone. The disgrace that fell in consequence on his superior, Ali escaped by the use of lavish bribes at Constantinople. In 1787 he took part in the war with Russia, and was rewarded by being made pasha of Trikala in Thessaly and derwend-pasha of Rumelia. It now suited his policy to suppress the brigands, which he did by enlisting most of them under his own banner. His power was now already considerable; and in 1788 he added to it by securing his nomination to the pashalik of Iannina by a characteristic trick.

The illiterate brigand, whose boyish ambition had not looked beyond the recovery of his father's beylick, was now established as one of the most powerful viziers under the Ottoman government. Success only stimulated his insatiable ambition. He earned the confidence of the Porte by the cruel discipline he maintained in his own sanjak, and the regular flow of tribute and bribes which he directed to Constantinople; while he bent all his energies to extending his territories at the expense of his neighbours. The methods he adopted would have done credit to Cesare Borgia; they may be studied in detail in the lurid pages of Pouqueville. Soon, by one means or another, his power was supreme in all central Albania. Two main barriers still obstructed the realization of his ambition, which now embraced Greece and Thessaly, as well as Albania, and the establishment in the Mediterranean of a sea-power which should rival that of the dey of Algiers. The first of these was the resistance of the little Christian hill community of Suli; the second the Venetian occupation of the coast, within a mile of which--by convention with the Porte--no Ottoman soldier might penetrate. It needed three several attacks before, in 1803, Ali conquered the Suliot stronghold. Events in western Europe gave him an earlier opportunity of becoming master of most of the coast towns. Ali had watched with interest the career of Bonaparte in Italy, and the treaty of Campo Formio (1797), which blotted the Venetian republic from the map of Europe, gave him the opportunity he desired. In response to his advances commissaries of the French republic visited him at Iannina and, affecting a sudden zeal for republican principles, he easily obtained permission to suppress the ``aristocratic'' tribes on the coast. His plans in Albania were interrupted by the war against Pasvan Oglu, the rebellious pasha of Widdin, in which Ali once more did good service. Meanwhile international politics had developed in a way that necessitated a change in Ali's attitude. Napoleon's occupation of the Ionian Islands and his relations with Ali had alarmed Russia, which feared that French influence would be substituted for her own in the Balkan peninsula; and on the 5th of September 1798 a formal alliance, to which Great Britain soon after acceded, was signed on behalf of the emperor Paul and the sultan. Once more Ali turned Turk and fought against his recent friends with such success that in the end he remained in possession of Butrinto, Prevesa and Vonitza on the coast, was created pasha ``of three tails'' by the sultan, and received the congratulations of Nelson. But the campaign of Austerlitz followed, then the peace of Pressburg which guaranteed to Napoleon the former dominions of Venice, and finally the treaty of Tilsit, which involved, among other things, the withdrawal of the Russians from the Ionian Islands and the Albanian coast.

Amid all the momentous changes the part of Ali was a difficult one. He had, moreover, to contend with domestic enemies, and with difficulty defeated a league formed against him by some Mussulman tribes, under Ibrahim of Berat and Mustapha of Delvinon, and the Suliots. He knew, however, how to retain the confidence of the sultan, who not only confirmed him in the possession of the whole of Albania from Epirus to Montenegro, but even in 1799 appointed him vali of Rumelia, an office which he held just long enough to enable him to return to Iannina laden with the spoils of Thessaly. He was now at the height of his power. In 1803 the Suliot stronghold fell; and he was undisputed master of Epirus, Albania and Thessaly, while the pashalik of the Morea was held by his son Veli, and that of Lepanto by his son Mukhtar. Only the little town of Parga held out against him on the coast; and in order to obtain this he once more in 1807 entered into an alliance with Napoleon. The French emperor, however, preferred to keep Parga, as a convenient gate into the Balkan peninsula, and it remained in French occupation until March 1814, when the Pargiots rose against the garrison and handed the fortress over to the British to save it from falling into the hands of Ali, who had bought the town from the French commander, Cozi Nikolo, and was closely investing it. The cordial relations between Napoleon and the pasha of Iannina had not long continued. Ali was angered by the refusal to surrender Parga and justly suspicious of the ambitions which this refusal implied; he could not feel himself secure with the Ionian Islands and the Dalmatian coast in the hands of a power whose plans in the East were notorious, and he was glad enough to avail himself of Napoleon's reverses in 1812 to help to rid himself of so dangerous a neighbor. His services to the allies received their reward. Still bent on obtaining Parga, he sent a special mission to London, backed by a letter from Sir Robert Liston, the British ambassador at Constantinople, calling the attention of the government to the pasha's supereminent qualities'' and his services against the French. After some hesitation it was decided to evacuate Parga and hand it over to the Ottoman government, i.e. Ali Pasha. The convention by which this was effected was ultimately signed on the 17th of May 1817, being ratified by the sultan on the 24th of April 1819. By its terms the Pargiots were to receive an asylum in the islands, the Ottoman government undertaking to pay compensation for their property. Ali had no difficulty in finding the money; the garrison, as soon as it was received, marched out with the bulk of the inhabitants; and the last citadel of freedom in the Balkans fell to the tyrant of Iannina.1

Ali's authority in the great part of the peninsula subject to him now overshadowed that of the sultan; and Mahmud II., whose whole policy had been directed to destroying the overgrown power of the provincial pashas, began to seek a pretext for overthrowing the Lion of Iannina, whose all-devouring ambition seemed to threaten his own throne. The occasion came in 1820 when Ali, emboldened by impunity, violated the sanctity of Stamboul itself by attempting to procure the murder of his enemy Pacho Bey in the very precincts of the palace. A decree of disposition was now issued against the sacrilegious vali, who had dared ``to fire shots in Constantinople, the residence of the caliph, and the centre of security.'' Its execution was entrusted to Khurshid Pasha, with the bulk of the Ottoman forces.

For two years Ali, now over eighty years of age, held his own, in spite of the defection of his vassals and even of his sons. At last, in the spring of 1822, after a prolonged siege in his island fortress at Iannina, which even the outbreak of the Greek revolt had not served to raise, the intrepid old man was forced to sue for terms. He asked and received an interview with Khurshid, was received courteously and dismissed with the most friendly assurances. As he turned to leave the grand vizier's tent he was stabbed in the back; his head was cut off and sent to Constantinople. Notwithstanding their treason to their father, his sons met with the same fate.

In spite of the ferocious characteristics which have been suggested in the above sketch, Ali Pasha is undoubtedly one of the most remarkable, as he is one of the most picturesque, figures in modern history; and as such he was recognized in his own day. His court at Iannina was the centre of a sort of barbarous culture, in which astrologers, alchemists and Greek poets played their part, and was often visited by travellers. Amongst others, Byron came, and has left a record of his impressions in ``Childe Harold's Pilgrimage,'' less interesting and vivid than the prose accounts of Pouqueville, T. S. Hughes and William M. Leake. Leake (iii. 259) reports a reproof addressed by Ali to the French renegade Ibrahim Effendi, who had ventured to remonstrate against some particular act of ferocity: ``At present you are too young at my court to know how to comport yourself. . . . You are not yet acquainted with the Greeks and Albanians: when I hang up one of these wretches on the plane-tree, brother robs brother under the very branches: if I burn one of them alive, the son is ready to steal his father's ashes to sell them for money. They are destined to be ruled by me; and no one but Ali is able to restrain their evil propensities.'' This is perhaps as good an apology as could be made for his character and methods. To the wild people over whom he ruled none was needed. He had their respect, if not their love; he is the hero of a thousand ballads; and his portrait still hangs among the ikons in the cottages of the Greek mountaineers. All accounts agree in describing him in later life as a man of handsome presence, with a venerable white beard, piercing black eyes and a benevolent cast of countenance, the effect of which was heightened in conversation by a voice of singular sweetness.

AUTHORITIES.--Apart from the scattered references in the published and unpublished diplomatic correspondence of the period, contemporary journals and books of travel contain much interesting material for the life of Ali. Of these may especially be mentioned Francois C. H. L. Pouqueville, Voyage en Moree, a Constantinople, en Albanie, &c. (3 vols., Paris, 1805), of which an English version by A. Plumptre was published in 1815; ib. Voyage dans la Grece (5 vols., Paris, 1820, 1821). Pouqueville, who spent some time as French resident at Iannina, had special facilities for obtaining firsthand information, though his emotionalism makes his observations and deductions at times somewhat suspect. Very interesting also are Thomas Smart Hughes, Travels in Greece and Albania (2 vols., 2nd ed., Lond. 1830); John Cam Hobhouse (Lord Broughton), A Journey through Albania, &c. . . . during the years 1809 and 1810 (Lond., 4to, 1813, a new ed., 2 vols., 1855); William Martin Leake, Travels in Northern Greece (4 vols., Lond. 1845). See also Pouqueville's Hist. de la regeneration de la Grece, 1740-1824 (4 vols., Paris, 1824, 3rd ed., Brussels, 1825); R. A. Davenport, Life of Ali Pasha, vizier of Epirus (1861). (W. A. P.)

1 In his report on the Ionian Treaty presented to Lord Castlereagh at the congress of Vienna in December 1814, Sir Richard Church strongly advocated, not only the retention of Parga, but that Vonitza, Prevesa and Butrinto also should be taken from Ali Pasha and placed under British protection, a measure he considered necessary. for the safety of the Ionian Islands. ``Ali Pasha,'' he wrote, ``is now busy building forts along his coast and strengthening his castles in the interior. In January 1814 he had 14,000 peasants at work on the castle of Argiro Castro, and about 1500 erecting a fort at Porto Palermo, nearly opposite Corfu.'' In 1810 he had erected a fort directly opposite Santa Maura commanding the harbour.

The fate of Parga created intense feeling at the time in England, and was cited by Liberals as a crowning instance of the perfidy of the government and of Castlereagh's subservience to reactionary tendencies abroad. The step, however, was not lightly taken. In occupying the town the British general had expressly refrained from pledging Great Britain to remain there; and the government held that any permanent occupation of a post on the mainland carried with it risks of complications out of all proportion to any possible benefit.

ALIAGA, a town of the province of Nueva Ecija, Luzon, Philippine Islands, about 70 m. N. by W. of Manila. Pop. (1903) 11,950. It has a comparatively cool and healthful climate, and is pleasantly situated about midway between the Pampanga Grande and the Pampanga Chico rivers, and in a large and fertile valley of which the principal products are Indian corn, rice, sugar and tobacco. Tagalog is the most important language; Ilocano, Pampango and Pangasinan are also used.

ALIAS (Lat. for ``at another time''), a term used to connect the different names of a person who has passed under more than one, in order to conceal his identity, or for other reasons; or, compendiously, to describe the adopted name. The expression alias dictus was formerly used in legal indictments, and pleadings where absolute precision was necessary in identifying the person to be charged, as ``John Jones, alias dictus James Smith.'' The adoption of a name other than a man's baptismal or surname need not necessarily be for the purpose of deception or fraud; pseudonyms or nicknames fall thus under the description of an alias. Where a person is married under an alias, the marriage is void when both parties have knowingly and wilfully connived at the adoption of the alias, with a fraudulent intention. But if one of the parties to a marriage has acquired a new name by use and reputation, or if the true name of any one of the parties is not known to the other, the use of an alias in these cases will not affect the validity of the marriage.

ALIBI (Lat. for ``elsewhere''), in law, the defence resorted to in criminal prosecutions, where the person charged alleges that he was so far distant at the time from the place where the crime was committed that he could not have been guilty. An alibi, if substantiated, is the most conclusive proof of innocence.

ALICANTE, a province of south-eastern Spain; bounded on the N. by Valencia, W. by Albacete and Murcia, S. by Murcia, and S.E. and E. by the Mediterranean Sea. Pop. (1900) 470,149; area, 2096 sq. m. Alicante was formed in 1833 of districts taken from the ancient provinces of Valencia and Murcia, Valencia contributing by far the larger portion. The surface of the province is extremely diversified. In the north and west there are extensive mountain ranges of calcareous formation, intersected by deep ravines; while farther south the land is more level, and there are many fertile valleys. On the Mediterranean coast, unhealthy salt marshes alternate with rich plains of pleasant and productive huertas or gardens, such as those of Alicante and Denia. Apart from Segura, which flows from the highlands of Albacete through Murcia and Orihuela to the sea, there is no considerable river, but a few rivulets flow east into the Mediterranean. The climate is temperate, and the rainfall very slight. Despite the want of rivers and of rain, agriculture is in a flourishing condition. Many tracts, originally rocky and sterile, have been irrigated and converted into vineyards and plantations. Cereals are grown, but the inhabitants prefer to raise such articles of produce as are in demand for export, and consequently part of the grain supply has to be imported. Esparto grass, rice, olives, the sugar-cane, and tropical fruits and vegetables are largely produced. Great attention is given to the rearing of bees and silk-worms; and the wine of the province is held in high repute throughout Spain, while some inferior kinds are sent to France to be mixed with claret. There are iron and lignite mines, but the output is small. Mineral springs are found at various places. The manufactures consist of fine cloths, silk, cotton, woollen and linen fabrics, girdles and lace, paper, hats, leather, earthenware and soap. There are numerous oil mills and brandy distilleries. Many of the inhabitants are engaged in the carrying trade, while the fisheries on the coast are also actively prosecuted, tunny and anchovies being caught in great numbers. Barilla is obtained from the sea-weed on the shores, and some of the saline marshes, notably those near Torrevieja, yield large supplies of salt. The principal towns, which are separately described, include Alicante, the capital (pop. 1900, 50,142), Crevillente (10,726), Denia (12,431), Elche (27,308), Novelda (11,388), Orihuela (28,530), and Villena (14,099). Other towns, of less importance, are Aspe (7927), Cocentaina (7093), Monovar (10,601), Pinoso (7946), and Villajoyosa (8902).

ALICANTE, the capital of the Spanish province described above, and one of the principal seaports of the country. Pop. (1900) 50,142. It is situated in 38 deg. 21' N. and 0 deg. 26' W., on the Bay of Alicante, an inlet of the Mediterranean Sea. It is the termini of railways from Madrid and Murcia. From its harbour, the town presents a striking picture. Along the shore extends the Paseo de los Martires, a double avenue of palms; behind this, the white flat-roofed houses rise in the form of a crescent towards the low hills which surround the city, and terminate, on the right, in a bare rock, 400 ft. high, surmounted by an ancient citadel. Its dry and equable climate renders Alicante a popular health-resort. The city is an episcopal see, and contains a modern cathedral.

The bay affords good anchorage, but only small vessels can come up to the two moles. The harbour is fortified, and there is a small lighthouse on the eastern mole; important engineering works, subsidized by the state, were undertaken in 1902 to provide better accomodation. In the same year 1737 vessels of 939,789 tons entered the port. The trade of Alicante consists chiefly in the manufacture of cotton, linen and woollen goods, cigars and confectionery; the importation of coal, iron, machinery, manures, timber, oak staves and fish; and the exportation of lead, fruit, farm produce and red wines, which are sent to France for blending with better vintages. Fine marble is procured in the island of Plana near the coast.

Alicante was the Roman Lucentum; but, despite its antiquity, it has few Roman or Moorish remains. In 718, it was occupied by the Moors, who were only expelled in 1304, and made an unsuccessful attempt to recapture the city in 1331. Alicante was besieged by the French in 1709, and by the Federalists of Cartagena in 1873. For an account of the events which led up to these two sieges, see SPAIN.,

For further details of the local history, see J. Pastor de la Roca, Historia general de la ciudad y castillo de Alicante, &c. (Alicante, 1854); and the Ensayo biografico bibliografico de escritores de Alicante y de su provincia, by M. R. Garcia and A. Montero y Perez (Alicante, 1890).

ALICE MAUD MARY, GRAND-DUCHESS OF HESSE-DARMSTADT (1843-1878), second daughter and third child of Queen Victoria, was born at Buckingham Palace, on the 25th of April 1843. A pretty, delicate-featured child--``cheerful, merry, full of fun and mischief,'' as her elder sister described her--fond of gymnastics, a good skater and an excellent horsewoman, she was a general favourite from her earliest days. Her first years were passed without particular incident in the home circle, where the training of their children was a matter of the greatest concern to the queen and the prince consort. Among other things, the royal children were encouraged to visit the poor, and the effect of this training was very noticeable in the later life of Princess Alice. After the marriage of the Princess Royal in 1858, the new responsibilities devolving upon Princess Alice, as the eldest daughter at home, called forth the higher traits of her character, and brought her into still closer relationship with her parents, and especially with her father. In the summer of 1860, at Windsor Castle, Princess Alice first met her future husband, Prince Louis of Hesse. An attachment quickly sprang up, and on the prince's second visit in November they were formally engaged. In the following year, on the announcement of the contemplated marriage, the House of Commons unanimously voted a dowry of L. 30,000 and an annuity of L. 6000 to the princess. In December 1861, while preparations were being made for the marriage, the prince consort was struck down with typhoid fever, and died on the 14th. Princess Alice nursed her father during his short illness with the utmost care, and after his death devoted herself to comforting her mother under this terrible blow. Her marriage took place at Osborne, on the 1st of July 1862. The princess unconsciously wrote her own biography from this period in her constant letters to Queen Victoria, a selection of which, edited by Dr. Carl Sell, were allowed to be printed in 1883. These letters give a complete picture of the daily life of the duke and duchess, and they also show the intense love of the latter for her husband, her mother and her native land. She managed to visit England every year, and it was at her special request that when she died her husband laid an English flag upon her coffin.

In the war between Austria and Prussia in 1866, Hesse- Darmstadt was upon the side of the Austrians; Prince Louis accompanied his troops to the front, and was duly appointed by the grand-duke to the command of the Hessian division. This was a time of intense trial to the princess, whose husband and brother-in-law, the crown prince of Prussia, were necessarily fighting upon opposite sides. The duke of Hesse also took part in the principal battles of the Franco-Prussian war, while the duchess was actively engaged in organizing hospitals for the relief of the sick and wounded. The death of the duke's father, Prince Charles of Hesse, on the 20th of March 1877, was followed by that of the grand-duke on the 13th of June, and Prince Louis succeeded to the throne as Grand Duke Louis IV. In the summer of 1878 the grand-duke and duchess, with their family, came again to England, and went to Eastbourne, where the duchess remained for some time. She returned to Darmstadt in the autumn, and on the 8th of November 1878 her daughter, Princess Victoria, was attacked by diphtheria. Three more of her children, as well as her husband, quickly caught the disease, and the youngest, ``May,'' succumbed on the 16th. On the 7th of December the princess was herself attacked, and, being weakened by nursing and anxiety, had not strength to resist the disease, which proved fatal on the 14th of December, the seventeenth anniversary of her father's death. She left one son and four daughters. .

See Carl Sell, Alice: Mittheilungen aus ihrem Leben und Briefen, &c. (Darmstadt, 1883), with English translation by the Princess Christian, Alice: biographical sketch and letters (1884). (G. F. B.)

ALIDADE (from the Arab.), the movable index of a graduated arc, used in the measurement of angles. The word is used also to designate the supporting frame or arms carrying the microscopes or verniers of a graduated circle.

ALIEN (Lat. alienus), the technical term applied by British constitutional law to anyone who does not enjoy the character of a British subject; in general, a foreigner who for the purposes of any state comes into certain domestic relations with it, other than those applying to native-born or naturalized citizens, but owns allegiance to a foreign sovereign.

English law, save with the special exceptions mentioned, admits to the character of subjects all who are born within the king's allegiance, that is, speaking generally, within the British dominions. In the celebrated question of the post-nati in the reign of James I. of England, it was found, after solemn trial, that natives of Scotland born before the union of the crowns were aliens in England, but that, since allegiance is to the person of the king, those born subsequently were English subjects. A child born abroad, whose father or whose grandfather on the father's side was a British subject, may claim the same character unless at the time of his birth his father was an attainted traitor, or in the service of a state engaged in war against the British empire (4th Geo. II. c. 21). Owing to this exceptional provision some sons of Jacobite refugees born abroad, who joined in the rebellion of 1745, were admitted to the privilege of prisoners of war.

It has been enacted in the United Kingdom with regard to the national status of women and children that a married woman is to be deemed a subject of the state of which her husband is for the time being a subject; that a natural-born British woman, having become an alien by marriage, and thereafter being a widow, may be rehabilitated under conditions slightly more favourable than are required for naturalization; that where a father or a widow becomes an alien, the children in infancy becoming resident in the country where the parent is naturalized, and being naturalized by the local law, are held to be subjects of that country; that those of a father or of a widow readmitted to British nationality or who obtains a certificate of naturalization, becoming during infancy resident with such parent in the British dominions in the former case or in the United Kingdom in the latter, become readmitted or naturalized (Naturalization Act 1870, s. 10). The nationality of children not covered by these enactments is not affected by the change of their parents' nationality. The same statute provides that a declaration of alienage before a justice of peace or other competent judge, having the effect of divesting the declarant of the character of a British subject, may be made by a naturalized British subject desiring to resume the nationality of the country to which he originally belonged, if there be a convention to that effect with that country; by natural-born subjects who were also born subjects of another state according to its law; or by persons born abroad having British fathers.

Naturalization, which means conferring the character of a subject, may now, under the act of 1870, be obtained by applying to the home secretary and producing evidence of having resided for not less than five years in the United Kingdom, or of having been in the service of the crown for not less than five years, and of intention to reside in the United Kingdom or serve under the crown. Such a certificate may be granted by the secretary of state to one naturalized previously to the passing of the act, or to a British subject as to whose nationality a doubt exists, or to a statutory alien, i.e. one who has become an alien by declaration in pursuance of the act of 1870.

In the United States the separate state laws largely determine the status of an alien, but subject to Federal treaties. (For further particulars see ALLEGIANCE and NATURALIZATION.)

Many of the disabilities to which aliens were subject in the United Kingdom, either by the common law or under various acts of parliament, have been repealed by the Naturalization Act 1870. It enables aliens to take, acquire, hold and dispose of real and personal property of every description, and to transmit a title to it, in all respects as natural-born British subjects. But the act expressly declares that this relaxation of the law does not qualify aliens for any office or any municipal, parliamentary or other franchise, or confer any right of a British subject other than those above expressed in regard to property, nor does it affect interests vested in possession or expectancy under dispositions made before the act, or by devolution of law on the death of any one dying before the act. A ship, any share in which is owned by an alien, shall not be deemed a British ship (Merchant Shipping Act 1894, s. i.) By the Juries Act 1870, s. 8, aliens who have been domiciled for ten years in England or Wales, if in other respects duly qualified, are liable to serve on juries or inquests in England or Wales; and by the Naturalization Act 1870, s. 5, the ahens' old privilege of being tried by a jury de medietate linguae (that is, of which half were foreigners), was abolished.

It seems to be a rule of general public law that an alien can be sent out of the realm by exercise of the crown's prerogative; but in modern English practice, whenever it seems necessary to expel foreigners (see EXPULSION), a special act of parliament has to be obtained for the purpose, unless the case falls within the extradition acts or the Aliens Act 1905. The latter prohibits the landing in the United Kingdom of undesirable alien steerage passengers, called in the act ``immigrants,'' from ships carrying more than twenty alien steerage passengers, called in the act ``immigrant ships''; nor can alien immigrants be landed except at certain ports at which there is an ``immigrant officer,'' to whom power of prohibiting the landing is given, subject to a right of appeal to the immigration board of the port. The act contains a number of qualifications, and among these empowers the secretary of state to exempt any immigrant ship from its provisions if he is satisfied that a proper system is maintained to prevent the immigration of undesirable persons. The principal test of undesirableness is not having or being in a position to obtain the means of supporting one's self and one's dependents, or appearing likely from disease or infirmity to become a charge on the rates, provided that the immigrant is not seeking to avoid prosecution or punishment on religious or political grounds, or persecution, involving danger of imprisonment or danger to life or limb, on account of religious belief. Lunatics, idiots, persons who from disease or infirmity appear likely to become a detriment to the public otherwise than through the rates, and persons sentenced in a foreign country for crimes for which they could be surrendered to that country, are also enumerated as undesirable. Power is also given to the secretary of state to expel persons sentenced as just mentioned, or, if recommended by the court in which they have been convicted, persons convicted of felony or some offence for which the court has power to impose imprisonment without the option of a fine, or of certain offences against the police laws; and persons in receipt of any such parochial relief as disqualifies for the parliamentary franchise, or wandering without ostensible mean of subsistence, or living under insanitary conditions due to overcrowding. (JNO. W.)

ALIENATION (from Lat. alienus, belonging to another), the act or fact of being estranged, set apart or separated. In law the word is used for the act of transfer of property by voluntary deed and not by inheritance. In regard to church property the word has come to mean, since the Reformation, a transfer from religious to secular ownership. ``Alienation'' is also used to denote a state of insanity (q.v..)

ALIEN-HOUSES, religious houses in England belonging to foreign ecclesiastics, or under their control. They generally were built where property had been left by the donors to foreign orders to pray for their souls. They were frequently regular ``priories,'' but sometimes only ``cells,'' and even ``granges,', with small chapels attached. Some, particularly in cities, seem to have been a sort of mission-houses. There were more than 100 in England. Many alien-houses were suppressed by Henry V. and the rest by Henry VIII.

ALIENIST (Lat. alienus, that which belongs to another, i.e. is external to one's self), one who specializes in the study of mental diseases, which are often included in the generic name ``Alienation.'' (See INSANITY.)

ALIGARH, a city and district of British India in the Meerut division of the United Provinces. The city, also known as Koil, was a station on the East Indian railway, 876 m. from Calcutta. Sir Sayad Ahmad Khan, K.C.S.I., who died in 1898, founded in 1864 the Aligarh Institute and Scientific Society for the translation into the vernacular of western literature; and afterwards the Mahommedan Anglo-Oriental College, under English professors, with an English school attached. The college meets with strong support from the enlightened portion of the Mussulman community, whose aim is to raise it to the status of a university, with the power of conferring degrees. The population (1901) 70,434, showed an increase of 14% in the decade. There are several flour-mills, cotton-presses and a dairy farm. Aligarh Fort, situated on the Grand Trunk road, consists of a regular polygon, surrounded by a very broad and deep ditch. It became a fortress of great importance under Sindhia in 1759, and was the depot where he drilled and organized his battalions in the European fashion with the aid of De Boigne. It was captured from the Mahrtatas under the leadership of Perron, another French officer, by Lord Lake's army, in September 1803, since which time it has been much strengthened and improved. In the rebellion of 1857 the troops stationed at Aligarh mutinied, but abstained from murdering their officers, who, with the other residents and ladies and children, succeeded in reaching Hathras.

The district of Aligarh has an area of 1857 sq. m. It is nearly a level plain, but with a slight elevation in the centre, between the two great rivers the Ganges and Jumna. The only other important river is the Kali Nadi, which traverses the entire length of the district from north-east to south-west. The district is traversed by several railways and also by the Ganges canal, which is navigable. The chief trading centre is Hathras. In 1901 the population was 1,200,822, showing an increase of 15% in the decade, due to the extension of irrigation. There are several factories for ginning and pressing cotton.

ALIGNMENT (from Fr. a and ligne, the Lat. linea, a line), a setting in line, generally straight, or the way in which the line runs; an expression used in surveying, drawing, and in military arrangements, the alignment of a regiment or a camp meaning the situation when drawn up in line or the relative position of the tents. The alignment of a rifle has reference to the way of getting the sights into line with the object, so as to aim correctly.

ALIMENT (from Lat. aliment-um, from alere to nourish), a synonym for ``food,'' literally or metaphorically. The word has also been used in the same legal sense as ALIMONY (q.v..) Aliment, in Scots law, is the sum paid or allowance given in respect of the reciprocal obligation of parents and children, husband and wife, grandparents and grandchildren, to contribute to each other's maintenance. The term is also used in regard to a similar obligation of other parties, as of creditors to imprisoned debtors, the payments by parishes to paupers, &c. Alimentary funds, whether of the kind above mentioned, or set apart as such by the deed of a testator, are intended for the mere support of the recipient, and are not attachable by creditors.

ALIMENTARY CANAL, in anatomy. The alimentary canal, strictly speaking, is the whole digestive tract from the mouth to the anus. From the one orifice to the other the tube is some 25 to 30 ft. long, and the food, in its passage, passes through the following parts one after the other:--mouth, pharynx, oesophagus, stomach, small intestines, caecum, large intestines, rectum and anus. Into this tube at various points the salivary glands, liver and pancreas pour their secretions by special ducts. As the mouth (q.v.) and pharynx (q.v.) are separately described, the detailed description will here begin with the oesophagus or gullet.

The oesophagus (Gr. oiso, I will carry, and fagein, to eat), a muscular tube lined with mucous membrane, stretches from the lower limit of the pharynx, at the level of the cricoid cartilage, to the cardiac orifice of the stomach. It is about 10 in. long (25 cm.) and half to one inch in diameter. At first it lies in the lower part of the neck, then in the thorax, and lastly, for about an inch, in the abdomen. As far as the level of the fourth or fifth thoracic vertebra it lies behind the trachea, but when that tube ends, it is in close contact with the pericardium, and, at the level of the tenth thoracic vertebra, passes through the oesophageal opening of the diaphragm (q.v.), accompanied by the two vagi nerves, the left being in front of it and the right behind. In the abdomen it lies just behind the left lobe of the liver. Both in the upper and lower parts of its course it lies a little to the left of the mid line. Its mucous membrane is thrown into a number of longitudinal pleats to allow stretching.

The stomach (Gr. stomachos) is an irregularly pear-shaped bag, situated in the upper and left part of the abdomen. It is somewhat flattened from before backward and so has an anterior and posterior surface and an upper and lower border. When moderately distended the thick end of the pear or fundus bulges upward and to the left, while the narrow end is constricted to form the pylorus, by means of which the stomach communicates with the small intestine. The cardiac orifice, where the oesophagus enters, is placed about a third of the way along the upper border from the left end of the fundus, and, between it and the pylorus, the upper border is concave and is known as the lesser curvature. From the cardiac to the pyloric orifice, round the lower border, is the greater curvature. The stomach has in front of it the liver (see fig. 1), the diaphragm and the anterior abdominal wall, while behind it are the pancreas, left kidney, left adrenal, spleen, colon and mesocolon. These structures form what is known as the stomach chamber. When the stomach is empty it contracts into a tubular organ which is frequently sharply bent, and the transverse colon ascends to occupy the vacant part of the stomach chamber.

The last inch of the stomach before reaching the pylorus is

From A. Birmingham; Cunningham's Text-Book of Anatomy.

FIG. 1.--The Abdominal Viscera in situ, as seen when the abdomen is laid open and the great omentum removed (drawn to scale from a photograph of a male body aged 56, hardened by formalin injections).

The ribs on the right side are indicated by Roman numerals; it will be observed that the eighth costal cartilage articulated with the sternum on both sides. The subcostal, intertubercular, and right and left Poupart lines are drawn in black, and the mesial plane is indicated by a dotted line. The intercostal muscles and part of the diaphragm have been removed, to show the liver and stomach extending up beneath the ribs. The stomach is moderately distended, and the intestines are particularly regular in their arrangement.

usually tubular and is known as the pyloric canal. Before reaching this there is a bulging known as the pyloric vestibule (see D. J. Cunningham, Tr. R. Soc. of Edinib. vol. xlv. pt. 1, No. 2). The pylorus is an oval opening, averaging half an inch in its long axis but capable of considerable distension; it is formed by a special development of the circular muscle layer of the stomach, and during life is probably tightly closed. The mucous membrane of the stomach is thrown into pleats or rugae when the organ is not fully distended, while between these it has a mammillated appearance.

Superficial to the mucous coat is a sub-mucous, consisting of loose connective tissue, while superficial to this are three coats of unstriped muscle, the inner oblique, the middle circular and the outer longitudinal. The peritoneal coat is described in the article on the coelom and serous membranes.

The small intestine is a tube, from 22 to 25 ft. long, beginning at the pylorus and ending at the ileo-caecal valve; it is divided into duodenum, jejunum and ileum.

The duodenum is from 9 to 11 in. long and forms a horseshoe or C-shaped curve, encircling the head of the pancreas. It differs from the rest of the gut in being retroperitoneal. Its first part is horizontal and lies behind the fundus of the gall-bladder, passing backward and to the right from the pylorus. The second part runs vertically downward in front of the hilum of the right kidney, and into this part the pancreatic and bile ducts open. The third part runs horizontally to the left in front of the aorta and vena cava, while the fourth part ascends to the left side of the second lumbar vertebra, after which it bends sharply downward and forward to form the duodeno-jejunal flexure.

The jejunum forms the upper two-fifths of the rest of the small intestine; it, like the ileum, is thrown into numerous convolutions and is attached by the mesentery to the posterior abdominal wall. (See COELOM AND SEROUS MEMBRANES.)

The ileum is the remaining three-fifths of the small intestine, though there is no absolute point at which the one ends and the other begins. Speaking broadly, the jejunum occupies the upper and left part of the abdomen below the subcostal plane (see ANATOMY: Superficial and Artistic), the ileum the lower and right part. About 3 ft. from its termination a small pouch, known as Meckel's diverticulum, is very occasionally found. At its termination the ileum opens into the large intestine at the ileo-caecal valve.

The caecum is a blind sac occupying the right iliac fossa and extending down some two or three inches below the ileo- caecal junction. From its posterior and left surface the vermiform appendix protrudes, and usually is directed upward and to the left, though it not infrequently hangs down into the true pelvis. This worm-like tube is blind at its end and is usually 3 or 4 in. long, though it has been seen as long as 10. in. Its internal opening into the caecum is about 1 in. below that of the ileum. On transverse section it is seen to be composed of (1) an external muscular coat, (2) a submucous coat, (3) a mass of lymphoid tissue, which appears after birth, and (4) mucous membrane. In many cases its lumen is wholly or partly obliterated, though this is probably due to disease (see R. Berry and L. Lack, Journ. Anat. & Phys. vol. H. p. 247). Guarding the opening of the ileum into the caecum is the ileo-caecal valve, which consists of two cusps projecting into the caecum; of these the upper forms a horizontal shelf, while the lower slopes up to it obliquely. Complete absence of the valve has been noticed, and in one such case the writer found that no abdominal inconvenience had been recorded during life. The caecum is usually completely covered by peritoneum, three special pouches of which are often found in its neighbourhood; of these the ileo-colic is just above the point of junction of the ileum and caecum, the ileocaecal just below that point, while the retro-caecal is behind the caecum. At birth the caecum is a cone, the apex of which is the appendix; it is bent upon itself to form a U, and sometimes this arrangement persists throughout life (see C. Toldt, ``Die Formbildung d. menschl. Blinddarmes,'' Sitz. der Wiener Akad. Bd. ciii. Abteil. 3, p. 41).

The ascending colon runs up from the caecum at the level of the ileo-caecal valve to the hepatic flexure beneath and behind the right lobe of the liver; it is about 8 in. long and posteriorly is in contact with the abdominal wall and right kidney. It is covered by peritoneum except on its posterior surface (see fig. 1).

The transverse colon is variable in position, depending largely on the distension of the stomach, but usually corresponding to the subcostal plane (see ANATOMY: Superficial and Artistic). On the left side of the abdomen it ascends to the splenic flexure, which may make an impression on the spleen (see DUCTLESS GLANDS), and is bound to the diaphragm opposite the eleventh rib by a fold of peritoneum called the phrenico-colic ligament. The peritoneal relations of this part are discussed in the article on the coelom and serous membranes.

The descending colon passes down in front of the left kidney and left side of the posterior abdominal wall to the crest of the ilium; it is about 6 in. long and is usually empty and contracted while the rest of the colon is distended with gas; its peritoneal relations are the same as those of the ascending colon, but it is more likely to be completely surrounded.

The iliac colon stretches from the crest of the ilium to the inner border of the psoas muscle, lying in the left iliac fossa, just above and parallel to Poupart's ligament. Like the descending, it is usually uncovered by peritoneum on its posterior surface. It is about 6 in. in length.

The pelvic colon lies in the true pelvis and forms a loop, the two limbs of which are superior and inferior while the convexity reaches across to the right side of the pelvis. In the foetus this loop occupies the right iliac fossa, but, as the caecum descends and enlarges and the pelvis widens, it is usually driven out of this region. The distal end of the loop turns sharply downward to reach the third piece of the sacrum where it becomes the rectum. To this pelvic colon Sir F. Treves (Anatomy of the Intestinal Canal, London, 1885) has given the name of the omega loop. Formerly the iliac and pelvic colons were spoken of as the sigmoid flexure, but Treves and T. Jonnesco (Le Colon pelvien pendant la vie intra-uterine, Paris, 1892) have pointed out the inapplicability of the term, and to the latter author the modern description is due.

The rectum, according to modern ideas, begins in front of the third piece of the sacrum; formerly the last part of the O (or omega) loop was described as its first part. It ends in a dilatation or rectal ampulla, which is in contact with the back of the prostate in the male and of the vagina in the female and is in front of the tip of the coccyx. The rectum is not straight, as its name would imply, but has a concavity forward corresponding to that of the sacrum and coccyx.

When viewed from in front three bends are usually seen, the upper and lower of which are sharply concave to the left, the middle one to the right. At the end of the pelvic colon the mesocolon ceases, and the rectum is then only covered by peritoneum at its sides and in front; lower down the lateral covering is gradually reflected off and then only the front is covered. About the junction of the middle and lower thirds of the tube the anterior peritoneal covering is also reflected off on to the bladder or vagina, forming the recto-vesical pouch in the male and the pouch of Douglas in the female. This reflexion is usually about 3 in. above the anal aperture, but may be a good deal lower.

The anal canal is the termination of the alimentary tract, and runs downward and backward from the lower surface of the rectal ampulla between the levatores ani muscles. It is about an inch long and its lateral walls are in contact, so that in section it appears as an antero-posterior slit (see J. Symington, Journ. Anat. and Phys. vol. 23, 1888).

Structure of the Intestine.--The intestine has four coats: serous, muscular, submucous and mucous. The serous or peritoneal coat has already been described wherever it is present. The muscular coat consists of unstriped fibres arranged in two layers, the outer longitudinal and the inner circular (see fig. 2). In the large intestine the longitudinal fibres, instead of being arranged evenly round the tube as they are in the small, are gathered into three longitudinal bands called taeniae (see fig. 1); by the contraction of these the large intestine is thrown into a series of sacculi or slight pouches. The taeniae in the caecum all lead to the vermiform appendix, and form a useful guide to this structure. In the rectum the three taeniae once more become evenly arranged over the whole surface of the bowel, but more thickly on the anterior and posterior parts. The circular layer is always thicker than the longitudinal; in the small intestine it decreases in thickness from the duodenum to the ileum, but in the large it gradually increases again, so that it is thickest in the duodenum and rectum.

The submucous coat is very strong and consists of loose areolar tissue in which the vessels break up.

The mucous coat is thick and vascular (see fig. 2); it consists of an epithelial layer most internally which forms the intestinal glands (see EPITHELIAL, ENDOTHELIAL AND GLANDULAR TISSUES.) External to this is the basement membrane, outside which is a layer of retiform tissue, and this is separated from the submucous coat by a very thin layer of unstriped muscle called the muscularis mucosae. In the duodenum and jejunum the mucous membrane is thrown into a series of transverse pleats called valvulae conniventes (see fig. 3); these begin about an inch from the pylorus and gradually fade away as the ileum is reached. About 4 in. from the pylorus the common bile and pancreatic ducts form a papilla, above which one of the valvulae conniventes makes a hood and below which a vertical fold, the frenulum, runs downward. The surface of the mucous membrane of the whole of the small intestine has a velvety appearance, due to the presence of closely-set, minute, thread-like elevations called vilii (see ffg. 2). Throughout the whole length of the intestinal tract are minute masses of lymphoid tissue called solitary glands (see fig. 2); these are especially numerous in the Caecum and appendix, while in the ileum they are collected into large oval patches, known as agminated glands or Peyer's patches, the long axes of which, from half an inch to 4 in. long, lie in the long axis of the bowel. They are always found in that part of the intestine which is furthest from the mesenteric attachment. In the interior of the rectum three shelf-like folds, one above the other, project into the cavity and correspond to the lateral concavities or kinks of the tube. They are not in the same line and the largest is usually on the right side. They are known as the plicae recti or valves of Houston. In the anal canal are four or five longitudinal folds called the columns of Morgagni. (For further details, see Quain's Anatomy, London, 1896; Gray's Anatomy, London, 1905; Cunningham's Anatomy, Edinburgh, 1906.)

Embryology.--The greater part of the alimentary canal is formed by the closing-in of the entoderm to make a longitudinal tube, ventral and parallel to the notochord. This tube is blind in front and behind (cephalad and caudad), but the middle part of its ventral wall is for some distance continuous with the wall of the yolk-sac, and this part of the canal, which at first opens into the yolk-sac by a very wide aperture, is called the mid gut. The part in front of it, which lies dorsal to the heart, is the fore gut, while the part behind the aperture of the yolk-sac is the hind gut.

The pharynx, oesophagus, stomach and part of the duodenum are developed from the fore gut, a good deal of the colon and the

From A. Birmingham; Cunningham's Text-Book of Anatomy. Fig. 3.--Valvulae Conniventes (natural size). A, As seen in a bit of jejunum which has been filled with alcohol and hardened.

B, A portion of fresh intestine spread out under water.

rectum from the hind gut, while the mid gut is responsible for the rest. The cephalic part of the fore gut forms the pharynx (q.v.), and about the fourth week the stomach appears as a fusiform dilatation in the straight tube. Between the two the oesophagus gradually forms as the embryo elongates. The opening into the yolk-sac, which at first is very wide, gradually narrows, as the ventral abdominal walls close in, until in the adult the only indication of the connexion between the gut and the yolk-sac is the very rare presence (about 2%) of Meckel's diverticulum already referred to. The stomach soon shows signs of the greater and lesser curvatures, the latter being ventral, but maintains its straight position. About the sixth week the caecum appears as a lateral diverticulum, and, until the third month, is of uniform calibre; after this period the terminal part ceases to grow at the same rate as the proximal, and so the vermiform appendix is formed. The mid gut forms a loop with its convexity toward the diminishing vitelline duct, or remains of the yolk-sac, and until the third month it protrudes into the umbilical cord. The greater curvature of the stomach grows more rapidly than the lesser, and the whole stomach turns over and becomes bent at right angles, so that what was its left surface becomes ventral. This turning over of the stomach throws the succeeding part of the intestine into a duodenal loop, which at first has a dorsal and ventral mesentery (see COELOM AND SEROUS MEMBRANES.) The intestine now grows very rapidly and is thrown into a series of coils; the caecum ascends and passes to the right ventral to the duodenum, and presses it against the dorsal wall of the abdomen; then it descends toward its permanent position in the right iliac fossa.

From the ventral surface on the hinder (caudal) closed end of the intestinal tube the allantois grows to form the placenta and bladder (see URINARY SYSTEM, REPRODUCTIVE SYSTEM and PLACENTA), and this region is the cloaca into which the alimentary, urinary and generative canals or ducts all open, but later two lateral folds appear which, by their union, divide the cloaca into a ventral and a dorsal part, the former being genito-urinary and the latter alimentary or intestinal. In this way the rectum or dorsal compartment is shut off from the genito-urinary. Later an ectodermal invagination at the hind end of the embryo develops and forms the anal canal; this is the proctodaeum, and for some time it is separated from the hind (caudal) end of the rectal part of the mesodaeum (or part of the intestinal canal formed from the mesoderm) by a membrane called the anal membrane. This is eventually absorbed and the digestive tract now communicates with the surface by the anus.

F. Wood Jones (British Medical Journal, 17th of December 1904) has given a somewhat different description of the development of the cloaca and anus, which better explains the various abnormalities met with in this region but requires further confirmation before it is generally accepted. For the development of the mouth, pharynx, lungs, liver and pancreas from the primitive alimentary canal, the reader is referred to the special articles on those structures. (For further details, see W. His, Anatomie menschlicher Embryonen (Leipzig, 1880-1885); C. S. Minot's Embryology (New York, 1897); and J. P. M`Murrich, Development of the Human Body (London, 1906). (F. G. P.)

Comparative Anatomy.--The primitive condition of the vertebrate alimentary canal may be described as a straight, simple tube, consisting of an anterior portion, the stomodaeum, formed by an ectodermal invagination, the mesenteron, a long median portion lined by endoderm, and a short posterior portion, the proctodaeum, formed by ectodermal invagination. In the lower vertebrates the primitive tube subserved also the purpose of respiration, and traces of the double function remain in the adult structure of all vertebrates (see MOUTH, PHARYNX.) In fish, the pharynx, or branchial region, suddenly becomes narrower, posterior to the gill-slits, to form the oesophagus; in higher animals the oesophagus, in the adult, is separated from the primitive pharyngeal region and lies dorsal to it. Probably, in the primitive vertebrata, the entire alimentary canal was lined with ciliated cells. Traces of this ciliation persist in many living forms. In the Ammocoete, the larval form of Petromyzon (see CYCLOSTOMATA), the whole canal is ciliated except the pharynx and the rectum; in the Dipnoi the epithelium of the stomach and the intestines is ciliated; in Selachii that of the posterior part of the gullet, and the spiral valve, is ciliated; extensive ciliation may occur in almost any region of the gut of the lower teleos. tomes, but in the higher forms (Teleostei) it is generally absent. In the latter, however, and in higher groups of vertebrates, a peculiar striated border on the columnar cells lining the intestinal tract has been held to be a final trace of ancestral ciliation.

The alimentary canal may be conveniently described in three divisions, the oesophagus or gullet, the passage by which food reaches the stomach, the stomach, typically an expanded region in which the food remains for a considerable time and is mechanically pulped, mixed with mucus and certain digestive juices (see NUTRITION) and partly macerated, the intestinal tract or gut, extending from the distal end of the stomach to the cloaca or anus, in which the food is subjected to further digestive action, but which is above all the region in which absorption of the products of digestion takes place, the refuse material together with quantities of waste matter entering the gut from the blood and liver being gradually passed towards the anus for discharge from the body.

The oesophagus is essentially merely a passage, as straight as may be, from the pharynx to the stomach, varying in length with the length of the neck and thoracic regions in different animals, and in calibre with the nature of the food. It is almost invariably lined with a many-layered epithelium, forming a tough coating, readily repaired and not easily damaged by hard food masses. It is occasionally separated from the stomach by a slight constriction which may be capable of contraction so as to prevent regurgitation. There are few exceptions to this structural and functional simplicity. In fishes (see ICHTHYOLOGY, Anatomy) the swim-bladder is developed as a dorsal outgrowth of the oesophagus and may remain in open connexion with it. In certain Teleosteis (e.g. Liitodeira) it is longer than the length it has to traverse and is thrown into convolutions. In many other fish, particularly Selachiis, a set of processes of the lining wall project into the cavity near the stomach and have been supposed to aid in preventing food particles, or living creatures swallowed without injury, escaping backwards into the mouth. In some egg-eating snakes the sharp tips of the ventral spines (hypapophyses) of the posterior cervical vertebrae penetrate the wall of the oesophagus and are used for breaking the shells of the eggs taken as food. In some aquatic Chelonians, the food of which consists chiefly of seaweeds, the lining membrane is produced into pointed processes backwardly directed. In birds this region frequently presents peculiarities. In Opisthocomus it forms an enormously wide double loop, hanging down over the breast-bone, which is peculiarly flattened and devoid of a keel in the anterior portion. In many birds part of the oesophagus may be temporarily dilated, forming a ``crop,'' as for instance in birds of prey and humming birds. In the flamingo, many ducks, storks, and the cormorant the crop is a permanent although not a highly specialized enlargement. Finally, in the vast majority of seed- eating birds, in gallinaceous birds, pigeons, sandgrouse, parrots and many Passeres, particularly the finches, the crop is a permanent globular dilatation, in which the food is retained for a considerable time, mixed with a slight mucous secretion, and softened and partly macerated by the heat of the body. Many birds feed their young from the soft contents of the crop, and in pigeons, at the breeding season, the cells lining the crop proliferate rapidly and are discharged as a soft cheesy mass into the cavity, forming the substance known as pigeon's milk. Amongst Mammalia, in Rodentia, Carnivora, elephants and ruminants, the wall of the oesophagus contains a layer of voluntary muscle, by the contraction of which these animals induce anti- peristaltic movements and can so regurgitate food into the mouth.

Stomach.--Where the oesophagus passes into the stomach, the lining wall of the alimentary tract changes from a many-layered epithelium to a mucous epithelium, consisting of a single layer of endodermal cells, frequently thrown into pits or projecting as processes; from being chiefly protective, it has become secretory and absorbing, and maintains this character to the distal extremity where it passes into the epiblast of the proctodaeum. In most cases the course of the alimentary canal from the distal end of the oesophagus to the cloaca or anus is longer than the corresponding region of the body, and the canal is therefore thrown into folds. The fundamental form of the stomach is a sac-like enlargement of the canal, the proximal portion of which is continuous with the line of the oesophagus, but the distal portion of which is bent in the proximal portion, the whole forming an enlarged bent tube. At the distal end of the tube the intestinal tract proper begins, and the two regions are separated by a muscular constriction. In fishes the stomach is generally in one of two forms; it may be a simple bent tube, the proximal limb of which is almost invariably much wider than the distal, anteriorly directed limb; or the oesophagus may pass directly into an expanded, globular or elongated sac, from the anterior lateral wall of which, not far from the oesophageal opening, the duodenum arises. In Batrachia and Reptilia the stomach is in most cases a simple sac, marked off from the oesophagus only by increased calibre. In the Crocodilia, however, the anterior portion of the stomach is much enlarged and very highly muscular, the muscles radiating from a central tendinous area on each of the flattened sides. The cavity is lined by a hardened secretion and contains a quantity of pebbles and gravel which are used in the mechanical trituration of the food, so that the resemblance to the gizzard of birds is well marked. This muscular chamber leads by a small aperture into a distal, smaller and more glandular chamber. In birds the stomach exhibits two regions, an anterior glandular region, the proventriculus, the walls of which are relatively soft and contain enlarged digestive glands aggregated in patches (e.g. some Steganopodes), in rows (e.g. most birds of prey) or in a more or less regular band. The distal region is larger and is lined in most cases by a more or less permanent lining which is thick and tough in birds with a muscular gizzard, very slight in the others. In many birds, specially those feeding on fish, the two regions of the stomach are of equal width, and are indistinguishable until, on opening the cavity, the difference in the character of the lining membrane becomes visible. In other birds the proventriculus is separated by a well marked constriction from the posterior and larger region. In graminiferous forms the latter becomes a thick-walled muscular gizzard, the muscles radiating from tendinous areas and the cavity containing pebbles or gravel.

In mammals, the primitive form of the stomach consists of a more or less globular or elongated expansion of the oesophageal region, forming the cardiac portion, and a forwardly curved, narrower pyloric portion, from which the duodenum arises. The whole wall is muscular, and the lining membrane is richly glandular. In the Insectivora, Carnivora, Perissodactyla, and in most Edentata, Chiroptera, Rodentia and Primates, this primitive disposition is retained, the difference consisting chiefly in the degrees of elongation of the stomach and the sharpness of the distal curvature. In other cases the cardiac portion may be prolonged into a caecal sac, a condition most highly differentiated in the blood-sucking bat, Desmodeus, where it is longer than the entire length of the body. There are two cardiac extensions in the hippopotamus and in the peccary. In many other mammals one, two or three protrusions of the cardiac region occur, whilst in the manatee and in some rodents the cardiac region is constricted off from the pyloric portion. In the Artiodactyla the stomach is always complex, the complexity reaching a maximum in ruminating forms. In the Suidae a cardiac diverticulum is partly constricted from the general cavity, forming an incipient condition of the rumen of true ruminants; the general cavity of the stomach shows an approach to the ruminant condition by the different characters of the lining wall in different areas. In the chevrotains, which in many other respects show conditions intermediate between nonruminant artiodactyles and true ruminants, the oesophagus opens into a wide cardiac portion, incompletely divided into four chambers. Three of these, towards the cardiac extremity, are lined with villi and correspond to the rumen or paunch; the fourth, which lies between the opening of the oesophagus and the pyloric portion of the stomach, is the ruminant reticulum and its wall is lined with very shallow ``cells.'' A groove runs along its dorsal wall from the oesophageal aperture to a very small cavity lined with low, longitudinally disposed folds, and forming a narrow passage between the cardiac and pyloric divisions; this is an early stage in the development of the omasum, psalterium or manyplies of the ruminant stomach. The fourth or true pyloric chamber is an elongated sac with smooth glandular walls and is the abomasum, or rennet sack. In the camel the rumen forms an enormous globular paunch with villous walls and internally showing a trace of division into two regions. It is well marked off from the reticulum, the ``cells'' of which are extremely deep, forming the well-known water-chambers. The psalterium is sharply constricted off from the reticulum and is an elongated chamber showing little trace of the longitudinal ridges characteristic of this region; it opens directly into the relatively small abomasum. In the true ruminants, the rumen forms a capacious, villous reservoir, nearly always partly sacculated, into which the food is passed rapidly as the animal grazes. The food is subjected to a rotary movement in the paunch, and is thus repeatedly subjected to moistening with the fluids secreted by the reticulum, as it is passed over the aperture of that cavity, and is formed into a rounded bolus. Most ruminants swallow masses of hairs, and these, by the rotary action of the paunch, are aggregated into peculiar dense, rounded balls which are occasionally discharged from the mouth and are known as ``hair-balls'' or ``bezoars.'' The food bolus, when the animal is lying down after grazing, is passed into the oesophagus and reaches the mouth by antiperistaltic contractions of the oesophagus. After prolonged mastication and mixing with saliva, it is again swallowed, but is now passed into the psalterium, which, in true ruminants, is a small chamber with conspicuous longitudinal folds. Finally it reaches the large abomasum where the last stages of gastric digestion occur.

In the Cetacea the stomach is different from that found in any other group of mammals. The oesophagus opens directly into a very large cardiac sac the distal extremity of which forms a long caecal pouch. At nearly the first third of its length this communicates by a narrow aperture into the elongated, relatively narrow pyloric portion. The latter is convoluted and constricted into a series of chambers that differ in different groups of Cetacea. In the Sirenia the stomach is divided by a constriction into a cardiac and a pyloric portion, and the latter has a pair of caeca. In most of the Marsupialia the stomach is relatively simple, forming a globular sac with the oesophageal and pyloric apertures closely approximated; in the kangaroos, on the other hand, the stomach is divided into a relatively small, caecal cardiac portion and an enormously long sacculated and convoluted pyloric region, the general arrangement of which closely recalls the large caecum of many mammals.

Intestinal Tract.--It is not yet possible to discuss the general morphology of this region in vertebrates as a group, as, whilst the modifications displayed in birds and mammals have been compared and studied in detail, those in the lower groups have not yet been systematically co-ordinated.

Fishes.--In the Cyclostomata, Holocephali and a few Teleostei the course of the gut is practically straight from the pyloric end of the stomach to the exterior, and there is no marked differentiation into regions. In the Dipnoi, a contracted sigmoid curve between the stomach and the dilated intestine is a simple beginning of the complexity found in other groups. In very many of the more specialized teleosteans, the gut is much convoluted, exhibiting a series of watchspring-like coils. In a number of different groups, increased surface for absorption is given, not by increase in length of the whole gut, but by the development of an internal fold known as the spiral valve. This was probably originally a longitudinal fold similar to the typhlosole of chaetopods. It forms a simple fold in the larval Ammocoete, and in its anterior region remains straight in some adult fish, e.g. Polypterus, but in the majority of cases it forms a complex spiral, wound round the inner wall of the expanded large intestine, the internal edge of the fold sometimes meeting to form a central column. It occurs in Cyclostomata, Selachii, Holocephali, Chondrostei, Crossopterygii, Amiidae, Lepidosteidae and Dipnoi. A set of organs peculiar to fish and known as the pyloric caeca are absent in Cyclostomata and Dipnoi, in most Selachii and in Amia, but present, in numbers ranging from one to nearly two hundred, in the vast majority of fish. These are outgrowths of the intestinal tract near the pyloric extremity of the stomach, and their function is partly glandular, partly absorbing. In a few Teleostei there is a single caecal diverticulum at the beginning of the ``rectum,'' and in the same region a solid rectal gland occurs in most elasmobranchs, whilst, again, in the Dipnoi a similar structure opens into the cloaca. These caeca have been compared with the colic caeca of higher vertebrates, but there is yet no exact evidence for the homology.

In the Batrachia the course of the intestinal tract is nearly straight from the pyloric end of the stomach to the cloaca, in the case of the perennibranchiates there being no more than a few simple loops between the expanded ``rectum'' and the straight portion that leaves the stomach. In the Caducibranchiata the anterior end of the enlarged rectum lies very close to the distal extremity of the stomach, and the gut, between these two regions, is greatly lengthened, forming a loop with many minor loops borne at the periphery of an expanse of mesentery, recalling the Meckelian tract of birds and mammals. In the tadpole this region is spirally coiled and is still longer relatively to the length of the whole tract. In Hyla and Pipa there is a small caecum comparable with the colic caecum of birds and mammals.

In Reptilia the configuration of the intestinal tract does not differ much from that in Batrachia, the length and complexity of the minor coils apparently varying with the general configuration of the body, that is to say, in reptiles with a long, narrow, and snake-like body the minor loops of the gut are relatively short and unimportant, whilst in those with a more spacious cavity, such as chelonians, many lizards and crocodiles, the gut may be relatively long and disposed in many minor coils. There is comparatively little differentiation between the mid-gut and the gut in cases where the whole gut is long; in the others the hind-gut is generally marked by an increase of calibre. A short caecal diverticulum, comparable with the colic caecum of birds and mammals, is present in many snakes and lizards and in some chelonians.

In fishes, batrachians and reptiles the intestinal tract is swung from the dorsal wall of the abdominal cavity by a mesentery which is incomplete on account of secondary absorption in places, and which grows out with the minor loops of the gut. There are also traces, more abundant in the lower forms, of the still more primitive ventral mesentery.

Intestinal Tract in Birds and Mammals.--There is no doubt but that the similarity of the modes of disposition of the alimentary tract in birds and mammals points to the probability of the chief morphological features of this region in these animals having been laid down in some common ancestor, although we

FIG. 4.--Intestinal Tract of Chauna chavaria. c.c. Colic caeca. p.v. Cut root of portal vein. d. Duodenum. r.v. Rectal vein. g. Glandular patch. s. Proventriculus. l.l. Meckel's tract. y. Meckel's diverticulum, or l.i. Hind-gut. Yolk-sac vestige. have not yet sufficient exact knowledge of the gut in Pisces, Batrachia and Reptilia to find amongst these with any certainty the most probable survival from the ancestral condition. The primitive gut must be supposed to have run backwards from the stomach to the cloaca suspended from the dorsal wall of the body-cavity by a dorsal mesentery. This tract, in the course of phylogeny of the common ancestors of birds and mammals, became longer than the straight length between its extreme points and, consequendy, was thrown into a series of folds. The mesentery grew out with these folds, but the presence of adjacent organs, the disturbance due to the outgrowth of the liver, and the secondary relations brought about between different portions of the gut, as the out-growing loops invaded each other's localities, disturbed the primitive simplicity. Three definite regions of outgrowth, however, became conspicuous and are to be recognized in the actual disposition of the gut in existing birds and mammals. The first of these is the duodenum. In the vast majority of birds, and in some of the simpler mammals, the portion of the gut immediately distal of the stomach grows out into a long and narrow loop (fig. 4, d), the proximal and distal ends of which are close together, whilst the loop itself may remain long and narrow, or may develop minor loops on its course. In mammals generally, however, the duodenum is complex and is not so sharply marked off from the distal portion of the gut as in birds. The second portion is Meckel's tract. It consists of the part generally known as the small intestines, the jejunum and ileum of human anatomy, and

Fig. 5,--Intestinal Tract of Canis vulpes. S, cut end of duodenum; C, caecum; R, cut end of rectum.

stretches from the distal end of the duodenum to the caecum or caeca. It is the chief absorbing portion of the gut, and in nearly all birds and mammals is the longest portion. It represents, however, only a very small part of the primitive straight gut, corresponding to not more than two or three somites of the embryo. This narrow portion grows out to form the greater part of what is called the pendent loop in mammalian embryology. Its anterior or proximal end lies close to the approximated

Fig. 6.--Intestinal Tract of Macropus bennetti. S, cut end of duodenum; R, cut end of rectum; C, caecum; C2, accessory caecum; C.L, colic loop of hind-gut.

proximal and distal ends of the duodenal loop, whilst its distal end passes into the hind-gut at the colic caecum or caeca. In the embryos of all birds and mammals, the median point of Meckel's tract, the part of the loop which has grown out farthest from the dorsal edge of the mesentery, is marked by the diverticulum caecum vitelli, the primitive connexion of the cavity of the gut with the narrowing stalk of the yolk-sac (fig. 4, y.) Naturally, in birds where the yolk-sac is of great functional importance this diverticulum is large, and in a majority of the families of birds persists throughout life, forming a convenient point of orientation. In mammals, no doubt in association with the functional reduction of the yolk-sac, this diverticulum, which is known as Meckel's diverticulum, has less importance, and whilst it has been observed in a small percentage of adult human subjects has not been recognized in the adult condition of any lower Mammalia.

In birds, Meckel's tract falls into minor folds or loops, the disposition of which forms a series of patterns remarkably different in appearance and characteristic of different groups. In fig. 4 an extremely primitive type is represented. In mammals Meckel's tract remains much more uniform; it may be short, or increase enormously in length, but in either case it falls into a fairly symmetrical shape, suspended at the circumference of a nearly circular expanse of mesentery. Where it is short it is thrown into very simple minor loops (figs. 5, 6 and 7); where it is long, these minor loops form a convoluted mass (figs. 8 abd 9).

FIG. 7.--Intestinal Tract of Tapir. S, cut end of duodenum; R, cut end of rectum; C, caecum; CL, colon.

The third portion of the gut should be termed the hind-gut and lies between the caecum or caeca and the anus, corresponding to the large intestines, colon and rectum of human anatomy. It is formed from a much larger portion of the primitive straight gut than the duodenum and Meckel's tract together, and its proximal portion, in consequence, lies very close to the origin of the duodenum. In the vast majority of birds, the hind-gut in the adult is relatively extremely short, often being only from

Fig. 8.--Intestinal Tract of Giraffe. S, cut end of duodenum; R, cut end of rectum; C, caecum; P.C.L, post-caecal loop; S.P, spiral loop; SF, third loop of hind-gut.

one-eighth to one-thirtieth of the whole length of the gut. A certain number of primitive birds, however, have retained a relatively long condition of the hind-gut (fig. 4), the greatest relative length occurring in struthious birds, and particularly in the ostrich, where the hind-gut exceeds in length the duodenum and Meckel's tract together. Mammals may be contrasted with birds as a group in which the hind-gut is always relatively long, sometimes extremely long, and in which, moreover, there is a strong tendency to differentiation of the hind-gut into regions the characters of which are of systematic importance. The first region is the colon, which forms a very simple expansion in mammals such as Carnivora (fig. 5), where the whole hind-gut is relatively short, or a series of simple loops in mammals in which the whole gut has a primitive disposition (e.g. Marsupialia, fig. 6). In the odd-toed Ungulata, the colon (fig. 7) forms an enormously long loop, the two limbs of which are closely approximated and the calibre of which is very large. In Ruminantia (fig. 8) the colon is still more highly differentiated, displaying first a simple wide loop, then a complicated watchspring-like coil, and finally a very long, irregular portion. In the higher Primates (fig. 9) it forms one enormous very wide loop, corresponding to the ascending, transverse and descending colons of human anatomy, and a shorter distal loop, the omega loop of human anatomy. Other striking patterns are displayed in other mammalian groups.

The second region of the hind-gut is usually known as the rectum. and although it is sometimes lengthened it is typically little longer than the portion of the primitive straight gut that it represents.

FIG. 9.--Intestinal Tract of Gorilla. S, cut end of duodenum; R, cut end of rectum; C, vermiform appendix of caecum; X, X2, X3, cut ends of factors of the portal vein.

Adaptations of the Intestinal Tract to Function.--The chief business of the gut is to provide a vascular surface to which the prepared food is applied so that the nutritive material may be absorbed into the system. Overlying and sometimes obscuring the morphological patterns of the gut, are many modifications correlated with the nature of the food and producing homoplastic resemblances independent of genetic affinity. Thus in birds and mammals alike there is a direct association of herbivorous habit with great relative length of gut. The explanation of this, no doubt, is simply that the vegetable matter which such creatures devour is in a form which requires not only prolonged digestive action, but, from the intimate admixture of indigestible material, a very large absorbing surface. In piscivorous birds and mammals, the gut is very long, with a thick wall and a relatively small calibre, whilst there is a general tendency for the regions of the gut to be slightly or not at all defined. Fish, as it is eaten by wild animals, contains a large bulk of indigestible matter, and so requires an extended absorbing surface; the thick wall and relatively small calibre are protections against wounding by fish bones. In frugivorous birds the gut is strikingly short, wide and simple, whilst a similar change has not taken place in frugivorous mammals. Carnivorous birds and mammals have a relatively short gut. In birds, generally, the relation of the length and calibre of the gut to the size of the whole creature is striking. If two birds of similar habit and of the same group be compared, it will be found that the gut of the larger bird is relatively longer rather than relatively wider. The same general rule applies to Meckel's tract in mammals, whereas in the case of the hind-gut increase of capacity is given by increase of calibre rather than by increased length.

The Colic Caeca.--These organs lie at the junction of the hind-gut with Meckel's tract and are homologous in birds and mammals although it happens that their apparent position differs in the majority of cases in the two groups. In most birds, the hind-gut is relatively very short, and the caecal position, accordingly, is at a very short distance from the posterior end of the body. whereas in most mammals the hind-gut is very long and the position of the caecum or caeca is relatively very much farther from the anus. Next, in most birds, the caeca when present are paired, whereas in most mammals there is only a single caecum. On the other hand, in certain birds (herons) as a normal occurrence, and in many birds as an individual variation, only a single caecum occurs. In some mammals, e.g. many armadillos, in Hyrax and the manatee, the caeca are normally paired; in many other (e.g. some rodents and marsupials) in addition to the normal caecum there is a reduced second caecum, whilst in quite a number of forms the relation of the caecum, ileum and colon at their junction is readily intelligible on the assumption that the caeca were originally paired. The origin and many of the peculiarities of the ileo-caecal valve find their best explanation on this hypothesis.

The caeca are hollow outgrowths of the wall of the gut, the blind ends being directed forwards. The caecal wall is in most cases highly glandular and contains masses of lymphoid tissue. In birds and in mammals this tissue may be so greatly increased as to transform the caecum into a solid or nearly solid sac, the calibre of which is for the most part smaller than that of the unmodified caecum. In some birds, the whole area of the caecum may be modified in this way; in mammals, it is generally the terminal portion, which then becomes the vermiform appendix, familiar in the anthropoid apes, in man and in some rodents. It is difficult to see in this modification merely a degeneration; not improbably it is the formation of a new glandular organ.

The caeca exhibit almost every gradation of development, from relatively enormous size to complete absence, and there is no definite, invariable connexion between the nature of the food and the degree of their development. In the case of birds, it may be said that on the whole the caeca are generally large in herbivorous forms and generally small in insectivorous, frugivorous, carnivorous and piscivorous forms, but there are many exceptions. Thus, owls and falcons have a diet that is closely similar, and yet owls have a pair of very long caeca, whilst in the Falconidae these organs are much reduced and apparently functionless. The insectivorous and omnivorous rollers, motmots and bee-eaters have a pair of large caeca, whilst in passerine birds of similar habit the caeca are vestigial glandular nipples. It is impossible to doubt that family history dominates in this matter. Certain families tend to retain the caeca, others to lose them, and direct adaptation to diet appears only to accelerate or retard these inherited tendencies. So also in mammals, no more than a general relation between diet and caecal development can be shown to exist, although the large size of the single caecum of mammals is more closely associated with a herbivorous as opposed to a carnivorous, frugivorous, piscivorous or omnivorous diet than is the case in birds. There is no relationship between diet and the complete or partial presence of both members of the primi-pair of caeca in mammals, the occurrence of the pair being rather an ``accident'' of inheritance than in any direct relation to function.

LITERATURE.--T. W. Bridge, in The Cambridge Natural History (vol. vii).; D. S. Jordan, A Guide to the Study of Fishes; R. Owen, Anatomy of Vertebrates; M. Weber, Die Saugethiere; W. H. Flower, The Organs of Digestien in Mammalia; R. Wiedersheim, Lehrbuch der vergleichenden Anatomie der Wirbelthiere; A. Oppel, Lehrbuch der vergleichenden mikroskopischen Anatomie der Wirbelthiere; Chalmers Mitchell, ``The Intestinal Tract of Birds,'' Transactions of the Linn. Soc. of London (vol. viii., 1901); and ``On the Intestinal Tract of Mammals,'' Transactions of the Zool. Soc. of London (vol. xvii., 1905). (In the two latter memoirs a fuller list of literature is given.) (P. C. M.)

ALIMONY (from Lat. afere, to nourish), in law the allowance for maintenance to which a wife is entitled out of her husband's estate for her support on a decree for judicial separation or for the dissolution of the marriage. Though, as a rule, payable to a wife, it may, if the circumstances of the case warrant it, be payable by the wife to the husband. Alimony is of two kinds, (a) temporary (pendente lite), and (b) permanent. Temporary alimony, or alimony pending suit, is the provision made by the husband for the wife in causes between them to enable her to live during the progress of the suit, and is allowed whether the suit is by or against the husband and whatever the nature of the suit may be. The usual English practice is to allot as temporary alimony about one-fifth of the husband's net income; where it appears that the husband has no means or is in insolvent circumstances, the court will refuse to allot temporary alimony. So where the wife is supporting herself by her own earnings, this fact will be taken into consideration. And where the wife and husband have lived apart for many years before the institution of the suit, and she has supported herself during the separation, no alimony will be allotted. Nor will the wife be entitled to alimony where she has sufficient means of support independent of her husband. Permanent alimony is that which is allotted to the wife after final decree. By the Matrimonial Causes Act 1907, the court may, if it think fit, on any decree for dissolution or nullity of marriage, order that the husband shall, to the satisfaction of the court, secure to the wife such a gross sum of money or such annual sum of money for any term not exceeding her life, as having regard to her fortune (if any), to the ability of her husband, and to the conduct of the parties, it may deem reasonable. The court may suspend the pronouncing of its decree until a proper deed or instrument has been executed by all necessary parties. The court may also make an order on the husband for payment to the wife during their joint lives of a reasonable monthly or weekly sum for her maintenance; the court may also at any time discharge, modify, suspend or increase the order according to the altered means of the husband; the court has also power to make provision for children. Alimony is paid direct to the wife or to a trustee or trustees on her behalf, but the court may impose any restrictions which seem expedient. We may also describe as a kind of alimony the allowance of a reasonable weekly sum not exceeding L. 2 which in England, under the Summary Jurisdiction (Married Women)