Act 1882, be sold under the direction of the court, and the money

arising under such sale is capital money. The court will only sanction such a sale if it be shown that it is to the benefit of all parties concerned; and if the article proposed to be sold is of unique or historical character, it will have regard to the intention of the settlor and the wishes of the remainder men (Re _Hope_, _De Cetto_ v. _Hope_, 1899, 2 ch. 679).

HEJAZ (HIJAZ), a Turkish vilayet and a province of Western Arabia, extending along the Red Sea coast from the head of the Gulf of Akaba in 29 deg. 30' N. to the south of Taif in 20 deg. N. It is bounded N. by Syria, E. by the Nafud desert and by Nejd and S. by Asir. Its length is about 750 m. and its greatest breadth from the Harra east of Khaibar to the coast is 200 m. The name Hejaz, which signifies "separating," is sometimes limited to the region extending from Medina in the north to Taif in the south, which separates the island province Nejd from the Tehama (Tihama) or coastal district, but most authorities, both Arab and European, define it in the wider sense. Though physically the most desolate and uninviting province in Arabia, it has a special interest and importance as containing the two sacred cities of Islam, Mecca and Medina (q.v.), respectively the birthplace and burial-place of Mahomet, which are visited yearly by large numbers of Moslem pilgrims from all parts of the world.

Hejaz is divided longitudinally by the Tehama range of mountains into two zones, a narrow littoral and a broader upland. This range attains its greatest height in Jebel Shar, the Mount Seir of scripture, overlooking the Midian coast, which probably reaches 7000 ft., and Jebel Radhwa a little N.E. of Yambu rising to 6000 ft. It is broken through by several valleys which carry off the drainage of the inland zone; the principal of these is the Wadi Hamd, the main source of which is on the Harra east of Khaibar. Its northern tributary the Wadi Jizil drains the Harrat el Awerid and a southern branch comes from the neighbourhood of Medina. Farther south the Wadi es Safra cuts through the mountains and affords the principal access to the valley of Medina from Yambu or Jidda. None of the Hejaz Wadis has a perennial stream, but they are liable to heavy floods after the winter rains, and thick groves of date-palms and occasional settlements are met with along their courses wherever permanent springs are found. The northern part of Hejaz contains but few inhabited sites. Muwela, Damgha and El Wijh are small ports used by coasting craft. The last named was formerly an important station on the Egyptian pilgrim route, and in ancient days was a Roman settlement, and the port of the Nabataean towns of el Hajr 150 m. to the east. Inland the sandstone desert of El Hisma reaches from the Syrian border at Ma'an to Jebel Awerid, where the volcanic tracts known as _harra_ begin, and extend southwards along the western borders of the Nejd plateau as far as the latitude of Mecca. East of Jebel Awerid lies the oasis of Tema, identified with the Biblical Teman, which belongs to the Shammar tribe; its fertility depends on the famous well, known as Bir el Hudaj. Farther south and on the main pilgrim route is El 'Ala, the principal settlement of El Hajr, the Egra of Ptolemy, to whom it was known as an oasis town on the gold and frankincense road. Higher up the same valley are the rock-cut tombs of Medina Salih, similar to those at Petra and shown by the Nabataean coins and inscriptions discovered there by Doughty and Huber to date from the beginning of the Christian era. To the south-east again is the oasis of Khaibar, with some 2500 inhabitants, chiefly negroes, the remnants of an earlier slave population. The citadel, known as the Kasr el Yahudi, preserves the tradition of its former Jewish ownership. With these exceptions there are no settled villages between Ma'an and Medina, the stations on the pilgrim road being merely small fortified posts with reservoirs, at intervals of 30 or 40 m., which are kept up by the Turkish government for the protection of the yearly caravan.

The southern part of the province is more favoured by nature. Medina is a city of 25,000 to 30,000 inhabitants, situated in a broad plain between the coast range and the low hills across which lies the road to Nejd. Its altitude above the sea is about 2500 ft. It is well supplied with water and is surrounded by gardens and plantations; barley and wheat are grown, but the staple produce, as in all the cultivated districts of Hejaz, is dates, of which 100 different sorts are said to grow. Yambu' has a certain importance as the port for Medina. The route follows for part of the way along the Wadi es Safra, which contains several small settlements with abundant date groves; from Badr Hunen, the last of these, the route usually taken from Medina to Mecca runs near the coast, passing villages with some cultivation at each stage. The eastern route though more direct is less used; it passes through a barren country described by Burton as a succession of low plains and basins surrounded by rolling hills and intersected by torrent beds; the predominant formation is basalt. Suwerikiya and Es Safina are the only villages of importance on this route.

Mecca and the holy places in its vicinity are described in a separate article; it is about 48 m. from the port of Jidda, the most important trade centre of the Hejaz province. The great majority of pilgrims for Mecca arrive by sea at Jidda. Their transport and the supply of their wants is therefore the chief business of the place; in 1904 the number was 66,500, and the imports amounted in value to L1,400,000.

From the hot lowland in which Mecca is situated the country rises steeply up to the Taif plateau, some 6000 ft. above sea-level, a district resembling in climate and physical character the highlands of Asir and Yemen. Jebel el Kura at the northern edge of the plateau is a fertile well-watered district, producing wheat and barley and fruit. Taif, a day's journey farther south, lies in a sandy plain, surrounded by low mountains. The houses, though small, are well built of stone; the gardens for which it is celebrated lie at a distance of a mile or more to the S.W. at the foot of the mountains.

Hejaz, together with the other provinces of Arabia which on the overthrow of the Bagdad Caliphate in 1258 had fallen under Egyptian domination, became by the conquest of Egypt in 1517 a dependency of the Ottoman empire. Beyond assuming the title of Caliph, neither Salim I. nor his successors interfered much in the government, which remained in the hands of the sharifs of Mecca until the religious upheaval which culminated at the beginning of the 19th century in the pillage of the holy cities by the Wahhabi fanatics. Mehemet Ali, viceroy of Egypt, was entrusted by the sultan with the task of establishing order, and after several arduous campaigns the Wahhabis were routed and their capital Deraiya in Nejd taken by Ibrahim Pasha in 1817. Hejaz remained in Egyptian occupation until 1845, when its administration was taken over directly by Constantinople, and it was constituted a vilayet under a vali or governor-general. The population is estimated at 300,000, about half of which are inhabitants of the towns and the remainder Bedouin, leading a nomad or pastoral life. The principal tribes are the Sherarat, Beni Atiya and Huwetat in the north; the Juhena between Yambu' and Medina, and the various sections of the Harb throughout the centre and south; the Ateba also touch the Mecca border on the south-east. All these tribes receive surra or money payments of large amount from the Turkish government to ensure the safe conduct of the annual pilgrimage, otherwise they are practically independent of the Turkish administration, which is limited to the large towns and garrisons. The troops occupying these latter belong to the 16th (Hejaz) division of the Turkish army.

The Hejaz railway.

The difficulties of communication with his Arabian provinces, and of relieving or reinforcing the garrisons there, induced the sultan Abdul Hamid in 1900 to undertake the construction of a railway directly connecting the Hejaz cities with Damascus without the necessity of leaving Turkish territory at any point, as hitherto required by the Suez Canal. Actual construction was begun in May 1901 and on the 1st of September 1904 the section Damascus-Ma'an (285 m.) was officially opened. The line has a narrow gauge of 1.05 metre = 41 in., the same gauge as that of the Damascus-Beirut line; it has a ruling gradient of 1 in 50 and follows generally the pilgrim track, through a desert country presenting no serious engineering difficulties. The graver difficulties due to the scarcity of water, and the lack of fuel, supplies and labour were successfully overcome; in 1906 the line was completed to El Akhdar, 470 m. from Damascus and 350 from Medina, In time to be used by the pilgrim caravan of that year; and the section to Medina was opened in 1908. Its military value was shown in the previous year, when it conveyed 28 battalions from Damascus to Ma'an, from which station the troops marched to Akaba for embarkation _en route_ to Hodeda. The length of the line from Damascus to Medina is approximately 820 m., and from Medina to Mecca 280 m.; the highest level attained is about 4000 ft. at Dar el Hamra in the section Ma'an-Medina.

AUTHORITIES.--J. L. Burckhardt, _Travels in Arabia_ (London, 1829); 'Ali Bey, _Travels_ (London, 1816); R. F. Burton, _Pilgrimage to Medinah and Mecca_ (1893); _Land of Midian_ (London, 1879); J. S. Hurgronje, _Mekka_ (Hague, 1888); C. M. Doughty, _Arabia Deserta_ (Cambridge, 1888); Auler Pasha, _Die Hedschasbahn_ (Gotha, 1906). (R. A. W.)

HEJIRA,[1] or HEGIRA (Arab. _hijra_, flight, departure from one's country, from _hajara_, to go away), the name of the Mahommedan era. It dates from 622, the year in which Mahomet "fled" from Mecca to Medina to escape the persecution of his kinsmen of the Koreish tribe. The years of this era are distinguished by the initials "A.H." (_anno hegirae_). The Mahommedan year is a lunar one, about 11 days shorter than the Christian; allowance must be made for this in translating _Hegira_ dates into Christian dates; thus A.H. 1321 corresponds roughly to A.D. 1903. The actual date of the "flight" is fixed as 8 Rabia I., i.e. 20th of September 622, by the tradition that Mahomet arrived at Kufa on the Hebrew Day of Atonement. Although Mahomet himself appears to have dated events by his flight, it was not till seventeen years later that the actual era was systematized by Omar, the second caliph (see CALIPHATE), as beginning from the 1st day of Muharram (the first lunar month of the year) which in that year (639) corresponded to July 16. The term _hejira_ is also applied in its more general sense to other "emigrations" of the faithful, e.g. to that to Abyssinia (see MAHOMET), and to that of Mahomet's followers to Medina before the capture of Mecca. These latter are known as _Muhajirun_.

For the problems of Moslem chronology and comparative tables of dates see (beside the articles CALENDAR, CHRONOLOGY and MAHOMET), Wustenfeld, _Vergleichungstabellen der muhammedanischen und christlichen Zeitrechnung_ (2nd ed., Leipzig, 1903); Mas Latrie, _Tresor de chronologie_ (Paris, 1889); Durbaneh, _Universal Calendar_ (Cairo, 1896); Winckler, _Altorientalische Forschungen_, ii. 326-350; D. Nielson, _Die altarabische Mondreligion_ (Strassburg, 1904); Hughes, _Dictionary of Islam_, s.v. "Hijrah."

FOOTNOTE:

[1] The _i_ in the second syllable is short.

HEL, or _Hela_, in Scandinavian mythology, the goddess of the dead. She was a child of Loki and the giantess Angurboda, and dwelt beneath the roots of the sacred ash, Yggdrasil. She was given dominion over the nine worlds of Helheim. In early myth all the dead went to her: in later legend only those who died of old age or sickness, and she then became synonymous with suffering and horror. Her dwelling was _Elvidnir_ (dark clouds), her dish _Hungr_ (hunger), her knife _Sullt_ (starvation), her servants _Ganglate_ (tardy feet), her bed _Kor_ (sickness), and her bed-curtains _Blikiandabol_ (splendid misery).

HELDENBUCH, DAS, the title under which a large body of German epic poetry of the 13th century has come down to us. The subjects of the individual poems are taken from national German sagas which originated in the epoch of the Migrations (_Volkerwanderung_), although doubtless here, as in all purely popular sagas, motives borrowed from the forces and phenomena of nature were, in course of time, woven into events originally historical. While the saga of the Nibelungs crystallized in the 13th century into the _Nibelungenlied_ (q.v.), and the Low German Hilde-saga into the epic of _Gudrun_ (q.v.) the poems of the _Heldenbuch_, in the more restricted use of that term, belong almost exclusively to two cycles, (1) the Ostrogothic saga of Ermanrich, Dietrich von Bern (i.e. Dietrich of Verona, Theodorich the Great) and Etzel (Attila), and (2) the cycle of Hugdietrich, Wolfdietrich and Ortnit, which like the _Nibelungen_ saga, was probably of Franconian origin. The romances of the _Heldenbuch_ are of varying poetic value; only occasionally do they rise to the height of the two chief epics, the _Nibelungenlied_ and _Gudrun_. Dietrich von Bern, the central figure of the first and more important group, was the ideal type of German medieval hero, and, under more favourable literary conditions, he might have become the centre of an epic more nationally German than even the _Nibelungenlied_ itself. Of the romances of this group, the chief are _Biterolf und Dietlieb_, evidently the work of an Austrian poet, who introduced many elements from the court epic of chivalry into a milieu and amongst characters familiar to us from the _Nibelungenlied_. _Der Rosengarten_ tells of the conflicts which took place round Kriemhild's "rose garden" in Worms--conflicts from which Dietrich always emerges victor, even when he is confronted by Siegfried himself. In _Laurin und der kleine Rosengarten_, the Heldensage is mingled with elements of popular fairy-lore; it deals with the adventures of Dietrich and his henchman Witege with the wily dwarf Laurin, who watches over another rose garden, that of the Tyrol. Similar in character are the adventures of Dietrich with the giants Ecke (_Eckenlied_) and Sigenot, with the dwarf Goldemar, and the deeds of chivalry he performs for queen Virginal (_Dietrichs erste Ausfahrt_)--all of these romances being written in the fresh and popular tone characteristic of the wandering singers or _Spielleute_. Other elements of the Dietrich saga are represented by the poems _Alpharts Tod_, _Dietrichs Flucht_ and _Die Rabenschlacht_ ("Battle of Ravenna"). Of these, the first is much the finest poem of the entire cycle and worthy of a place beside the best popular poetry of the Middle High German epoch. Alphart, a young hero in Dietrich's army, goes out to fight single-handed with Witege and Heime, who had deserted to Ermanrich, and he falls, not in fair battle, but by the treachery of Witege whose life he had spared. The other two Dietrich epics belong to a later period, the end of the 13th century--the author being an Austrian, Heinrich der Vogler--and show only too plainly the decay that had by this time set in in Middle High German poetry.

The second cycle of sagas is represented by several long romances, all of them unmistakably "popular" in tone--conflicts with dragons, supernatural adventures, the wonderland of the East providing the chief features of interest. The epics of this group are _Ortnit_, _Hugdietrich_, _Wolfdietrich_, the latter with its pathetic episode of the unswerving loyalty of Wolfdietrich's vassal Duke Berchtung and his ten sons. Although many of the incidents and motives of this cycle are drawn from the best traditions of the _Heldensage_, its literary value is not very high.

This collection of popular romances was one of the first German books to be printed. The date of the first edition is unknown, but the second edition appeared in the year 1491 and was followed by later reprints in 1509, 1545, 1560 and 1590. The last of these forms the basis of the text edited by A. von Keller for the Stuttgart _Literarische Verein_ in 1867. In 1472 the _Heldenbuch_ was adapted to the popular tastes of the time by being remodelled in rough _Knittelvers_ or doggerel; the author, or at least copyist, of the MS. was a certain Kaspar von dor Roen, of Munnerstadt in Franconia. This version was printed by F. von der Hagen and S. Primisser in their _Heldenbuch_ (1820-1825). _Das Heldenbuch_, which F. von der Hagen published in 2 vols, in 1855, was the first attempt to reproduce the original text by collating the MSS. A critical edition, based not merely on the oldest printed text--the only one which has any value for this purpose, as the others are all copies of it--but also on the MSS., was published in 5 vols. by O. Janicke, E. Martin, A. Amelung and J. Zupitza at Berlin (1866-1873). A selection, edited by E. Henrici, will be found in Kurschner's _Deutsche Nationalliteratur_, vol. 7 (1887). Recent editions have appeared of _Der Rosengarten_ and _Laurin_, by G. Holz (1893 and 1897). All the poems have been translated into modern German by K. Simrock and others. See F. E. Sandbach, _The Heroic Saga-Cycle of Dietrich of Bern_ (1906). The literature of the _Heldensage_ is very extensive. See especially W. Grimm, _Die deutsche Heldensage_ (3rd ed., 1889); L. Uhland, "Geschichte der deutschen Poesie im Mittelalter," _Schriften_, vol. i. (1866); O. L. Jiriczek, _Deutsche Heldensage_, vol. i. (1898); and especially B. Symons, "Germanische Heldensage," in Paul's _Grundriss der germanischen Philologie_ (2nd ed., 1898).

HELDER, a seaport town at the northern extremity of the province of North Holland, in the kingdom of Holland, 51 m. by rail N.N.W. of Amsterdam. Pop. (1900) 25,842. It is situated on the Marsdiep, the channel separating the island of Texel from the mainland, and the main entrance to the Zuider Zee, and besides being the terminus of the North Holland canal from Amsterdam, it is an important naval and military station. On the east side of the town, called the Nieuwe Diep, is situated the fine harbour, which formerly served, as Ymuiden now does, as the outer port of Amsterdam. In this neighbourhood are the naval wharves and magazines, wet and dry docks, and the naval cadet school of Holland, the name Willemsoord being given to the whole naval establishment. From Nieuwe Diep to Fort Erfprins on the west side of the town, a distance of about 5 m., stretches the great sea-dike which here takes the place of the dunes. This dike descends at an angle of 40 deg. for a distance of 200 ft. into the sea, and is composed of Norwegian granite and Belgian limestone, strengthened at intervals by projecting jetties of piles and fascines. A circle of forts and batteries defends the town and coast, and there is a permanent garrison of 7000 to 9000 men, while 30,000 men can be accommodated within the lines, and the province flooded from this point. Besides several churches and a synagogue, there are a town hall (1836), a hospital, an orphan asylum, the "palace" of the board of marine, a meteorological observatory, a zoological station and a lighthouse. The industries of the town are sustained by the garrison and marine establishments.

HELEN, or HELENA (Gr. [Greek: Elene]),in Greek mythology, daughter of Zeus by Leda (wife of Tyndareus, king of Sparta), sister of Castor, Pollux and Clytaemnestra, and wife of Menelaus. Other accounts make her the daughter of Zeus and Nemesis, or of Oceanus and Tethys. She was the most beautiful woman in Greece, and indirectly the cause of the Trojan war. When a child she was carried off from Sparta by Theseus to Attica, but was recovered and taken back by her brothers. When she grew up, the most famous of the princes of Greece sought her hand in marriage, and her father's choice fell upon Menelaus. During her husband's absence she was induced by Paris, son of Priam, with the connivance of Aphrodite, to flee with him to Troy. After the death of Paris she married his brother Deiphobus, whom she is said to have betrayed into the hands of Menelaus at the capture of the city (_Aeneid_, vi. 517 ff.). Menelaus thereupon took her back, and they returned together to Sparta, where they lived happily till their death, and were buried at Therapnae in Laconia. According to another story, Helen survived her husband, and was driven out by her stepsons. She fled to Rhodes, where she was hanged on a tree by her former friend Polyxo, to avenge the loss of her husband Tlepolemus in the Trojan War (Pausanias iii. 19). After death, Helen was said to have married Achilles in his home in the island of Leuke. In another version, Paris, on his voyage to Troy with Helen, was driven ashore on the coast of Egypt, where King Proteus, upon learning the facts of the case, detained the real Helen in Egypt, while a phantom Helen was carried off to Troy. Menelaus on his way home was also driven by stress of winds to Egypt, where he found his wife and took her home (Herodotus ii. 112-120; Euripides, _Helena_). Helen was worshipped as the goddess of beauty at Therapnae in Laconia, where a festival was held in her honour. At Rhodes she was worshipped under the name of Dendritis (the tree goddess), where the inhabitants built a temple in her honour to expiate the crime of Polyxo. The Rhodian story probably contains a reference to the worship connected with her name (cf. Theocritus xviii. 48 [Greek: sebou m', Helenas phyton eimi]). She was the subject of a tragedy by Euripides and an epic by Colluthus. Originally, Helen was perhaps a goddess of light, a moon-goddess, who was gradually transformed into the beautiful heroine round whom the action of the _Iliad_ revolves. Like her brothers, the Dioscuri, she was a patron deity of sailors.

See E. Oswald, _The Legend of Fair Helen_ (1905); J. A. Symonds, _Studies of the Greek Poets_, i. (1893); F. Decker, _Die griechische Helena in Mythos und Epos_ (1894); Andrew Lang, _Helen of Troy_ (1883); P. Paris in Daremberg and Saglio's _Dictionnaire des antiquites_; the exhaustive article by R. Engelmann in Roscher's _Lexikon der Mythologie_; and O. Gruppe, _Griechische Mythologie_, i. 163, according to whom Helen originally represented, in the Helenephoria (a mystic festival of Artemis, Iphigeneia or Tauropolos), the sacred basket ([Greek: helene]) in which the holy objects were carried; and hence, as the personification of the initiation ceremony, she was connected with or identified with the moon, the first appearance of which probably marked the beginning of the festivity.

HELENA, ST (c. 247-c. 327) the wife of the emperor Constantius I. Chlorus, and mother of Constantine the Great. She was a woman of humble origin, born probably at Drepanum, a town on the Gulf of Nicomedia, which Constantine named Helenopolis in her honour. Very little is known of her history. It is certain that, at an advanced age, she undertook a pilgrimage to Palestine, visited the holy places, and founded several churches. She was still living at the time of the murder of Crispus (326). Constantine had coins struck with the effigy of his mother. The name of Helena is intimately connected with the commonly received story of the discovery of the Cross. But the accounts which connect her with the discovery are much later than the date of the event. The Pilgrim of Bordeaux (333), Eusebius and Cyril of Jerusalem were unaware of this important episode in the life of the empress. It was only at the end of the 4th century and in the West that the legend appeared. The principal centre of the cult of St Helena in the West seems to be the abbey of Hautvilliers, near Reims, where since the 9th century they have claimed to be in possession of her body. In England legends arose representing her as the daughter of a prince of Britain. Following these Geoffrey of Monmouth makes her the daughter of Coel, the king who is supposed to have given his name to the town of Colchester. These legends have doubtless not been without influence on the cult of the saint in England, where a great number of churches are dedicated either to St Helena alone, or to St Cross and St Helena. Her festival is celebrated in the Latin Church on the 18th of August. The Greeks make no distinction between her festival and that of Constantine, the 21st of May.

See _Acta sanctorum_, Augusti iii. 548-580; Tixeront, _Les Origines de l'eglise d'Edesse_ (Paris, 1888); F. Arnold-Forster, _Studies in Church Dedications or England's Patron Saints_, i. 181-189, iii. 16, 365-366 (1899). (H. De.)

HELENA, a city and the county-seat of Phillips county, Arkansas, U.S.A., situated on and at the foot of Crowly's Ridge, about 150 ft. above sea-level, in the alluvial bottoms of the Mississippi river, about 65 m. by rail S.W. of Memphis, Tennessee. Pop. (1890) 5189, (1900) 5550, of whom 3400 were negroes; (1910) 8772. It is served by the Yazoo & Mississippi Valley (Illinois Central), the St Louis, Iron Mountain & Southern (Missouri Pacific), the Arkansas Midland, and the Missouri & North Arkansas railways. Built in part upon "made land," well protected by levees, and lying within the richest cotton-producing region of the south, the rich timber country of the St Francis river, and the Mississippi "bottom lands," Helena concentrates its economic interests in cotton-compressing and shipping, the manufacture of cotton-seed products, lumbering and wood-working. The city was founded about 1821, but so late as 1860 the population was only 800. During the Civil War the place was of considerable strategic importance. It was occupied in July 1862 by the Union forces, who strongly fortified it to guard their communications with the lower Mississippi; on the 4th of July 1863, when occupied by General Benjamin M. Prentiss (1819-1901) with 4500 men, it was attacked by a force of 9000 Confederates under General Theophilus H. Holmes (1804-1880), who hoped to raise the siege of Vicksburg or close the river to the Union forces. The attack was repulsed, with a loss to the Confederates of one-fifth their numbers, the Union loss being slight.

HELENA, a city and the county-seat of Lewis and Clark county, Montana, U.S.A., and the capital of the state, at the E. base of the main range of the Rocky Mountains, 80 m. N.E. of Butte, at an altitude of about 4000 ft. Pop. (1880) 3624; (1890) 13,834; (1900) 10,770, of whom 2793 were foreign-born; (1910 census) 12,515. It is served by the Great Northern and the Northern Pacific railways. Helena is delightfully situated with Mt Helena as a background in the hollow of the Prickly Pear valley, a rich agricultural region surrounded by rolling hills and lofty mountains, and contains many fine buildings, including the state capitol, county court house, the Montana club house, high school, the cathedral of St Helena, a federal building, and the United States assay office. It is the seat of the Montana Wesleyan University (Methodist Episcopal), founded in 1890; St Aloysius College and St Vincent's Academy (Roman Catholic); and has a public library with about 35,000 volumes, the Montana state library with about 40,000 volumes, and the state law library with about 24,000 volumes. The city is the commercial and financial centre of the state (Butte being the mining centre), and is one of the richest cities in the United States in proportion to its population. It has large railway car-shops, extensive smelters and quartz crushers (at East Helena), and various manufacturing establishments; the value of the factory product in 1905 was $1,309,746, an increase of 68.7% over that of 1900. The surrounding country abounds in gold- and silver-bearing quartz deposits, and it is estimated that from the famous Last Chance Gulch alone, which runs across the city, more than $40,000,000 in gold has been taken. The street railway and the lighting system of the city are run by power generated at a plant and 40 ft. dam at Canyon Ferry, on the Missouri river, 18 m. E. of Helena. There is another great power plant at Hauser Plant, 20 m. N. of Helena. Three miles W. of the city is the Broadwater Natatorium with swimming pool, 300 ft. long and 100 ft. wide, the water for which is furnished by hot springs with a temperature at the source of 160 deg. Fort Harrison, a United States army post, is situated 3 m. W. of the city. Helena was established as a placer mining camp in 1864 upon the discovery of gold in Last Chance Gulch. The town was laid out in the same year, and after the organization of Montana Territory it was designated as the capital. Helena was burned down in 1869 and in 1874. It was chartered as a city in 1881.

HELENSBURGH, a municipal and police burgh and watering-place of Dumbartonshire, Scotland, on the N. shore of the Firth of Clyde, opposite Greenock, 24 m. N.W. of Glasgow by the North British railway. Pop. (1901) 8554. There is a station at Upper Helensburgh on the West Highland railway, and from the railway pier at Craigendoran there is steamer communication with Garelochhead, Dunoon and other pleasure resorts on the western coast. In 1776 the site began to be built upon, and in 1802 the town, named after Lady Helen, wife of Sir James Colquhoun of Luss, the ground landlord, was erected into a burgh of barony, under a provost and council. The public buildings include the burgh hall, municipal buildings, Hermitage schools and two hospitals. On the esplanade stands an obelisk to Henry Bell, the pioneer of steam navigation, who died at Helensburgh in 1830.

HELENUS, in Greek legend, son of Priam and Hecuba, and twin-brother of Cassandra. He is said to have been originally called Scamandrius, and to have received the name of Helenus from a Thracian soothsayer who instructed him in the prophetic art. In the _Iliad_ he is described as the prince of augurs and a brave warrior; in the _Odyssey_ he is not mentioned at all. Various details concerning him are added by later writers. It is related that he and his sister fell asleep in the temple of Apollo Thymbraeus and that snakes came and cleansed their ears, whereby they obtained the gift of prophecy and were able to understand the language of birds. After the death of Paris, Helenus and his brother Deiphobus became rivals for the hand of Helen. Deiphobus was preferred, and Helenus withdrew in indignation to Mount Ida, where he was captured by the Greeks, whom he advised to build the wooden horse and carry off the Palladium. According to other accounts, having been made prisoner by a stratagem of Odysseus, he declared that Philoctetes must be fetched from Lemnos before Troy could be taken; or he surrendered to Diomedes and Odysseus in the temple of Apollo, whither he had fled in disgust at the sacrilegious murder of Achilles by Paris in the sanctuary. After the capture of Troy, he and his sister-in-law Andromache accompanied Neoptolemus (Pyrrhus) as captives to Epirus, where Helenus persuaded him to settle. After the death of Neoptolemus, Helenus married Andromache and became ruler of the country. He was the reputed founder of Buthrotum and Chaonia, named after a brother or companion whom he had accidentally slain while hunting. He was said to have been buried at Argos, where his tomb was shown. When Aeneas, in the course of his wanderings, reached Epirus, he was hospitably received by Helenus, who predicted his future destiny.

Homer, _Iliad_, vi. 76, vii. 44, xii. 94, xiii. 576; Sophocles, _Philoctetes_, 604, who probably follows the _Little Iliad_ of Lesches; Pausanias i. 11, ii. 23; Conon, _Narrationes_, 34; Dictys Cretensis iv. 18; Virgil, _Aeneid_, iii. 294-490; Servius on _Aeneid_, ii. 166, iii. 334.

HELGAUD, or HELGALDUS (d. c. 1048), French chronicler, was a monk of the Benedictine abbey of Fleury. Little else is known about him save that he was chaplain to the French king, Robert II. the Pious, whose life he wrote. This _Epitoma vitae Roberti regis_, which is probably part of a history of the abbey of Fleury, deals rather with the private than with the public life of the king, and its value is not great either from the literary or from the historical point of view. The only existing manuscript is in the Vatican, and the _Epitoma_ has been printed by J. P. Migne in the _Patrologia Latina_, tome cxli. (Paris, 1844); and by M. Bouquet in the _Recueil des historiens des Gaules_, tome x. (Paris, 1760).

See _Histoire litteraire de la France_, tome vii. (Paris, 1865-1869); and A. Molinier, _Les Sources de l'histoire de France_, tome ii. (Paris, 1902).

HELGESEN, POVL,[1] Danish humanist, was born at Varberg in Halland about 1480, of a Danish father and a Swedish mother. Helgesen was educated first at the Carmelite monastery of his native place and afterwards at another monastery at Elsinore, where he devoted himself to humanistic studies and adopted Erasmus as his model. None had a keener eye for the abuses of the Church; long before the appearance of Luther, he denounced the ignorance and immorality of the clergy, and, as lector at the university of Copenhagen, gathered round him a band of young enthusiasts, the future leaders of the Danish Reformation. But Helgesen desired an orderly, methodical, rational reformation, and denounced Luther, whose ablest opponent in Denmark he subsequently became, as a hot-headed revolutionist. Christian II. was also an object of Helgesen's detestation, and so boldly did he oppose that monarch's measures that, to save his life, he had to flee to Jutland. Under Frederick I. (1523-1533) he returned to Copenhagen and resumed his chair at the university, becoming soon afterwards provincial of the Carmelite Order for Scandinavia. But like all moderate men in a time of crisis, Helgesen could gain the confidence of neither party, and was frequently attacked as bitterly by the Catholics as by the Protestants. From 1530 to 1533 he and the Protestant champion Hans Tausen exhausted the whole vocabulary of vituperation in their fruitless polemics. In October 1534, however, Helgesen issued an eirenicon in which he attempted to reconcile the two contending confessions. After that every trace of him is lost. For a long time he was unjustly regarded as a turn-coat, but he was too superior to the prejudices of his age to be understood by his contemporaries. His ideal was a moral internal reformation of the Church on a rational basis, conducted not by ill-informed fanatics, but by an enlightened and well-educated clergy; and from this standpoint he never diverged. Helgesen was indisputably the greatest master of style of his age in Denmark, and as a historian he also occupies a prominent position. He always endeavours to probe down to the very soul of things, though his passionate nature made it very difficult for him to be impartial. His chief works are _Danmark's Kongers Historie_ and _Skibby Kroniken_.

See Ludwig Schmitt, _Der Karmeliter Paulus Helia_ (Freiburg, 1893); _Danmarks Riges Historie_ (Copenhagen, 1897-1905), vol. iii.

FOOTNOTE:

[1] He wrote his name Heliae or Eliae.

HELIACAL, relating to the sun ([Greek: helios]), a term applied in the ancient astronomy to the first rising of a star which could be seen after it emerged from the rays of the sun, or the last setting that could be seen before it was lost from sight by proximity to the sun.

HELIAND. The 9th-century poem on the Gospel history, to which its first editor, J. A. Schmeller, gave the appropriate name of _Heliand_ (the word used in the text for "Saviour," answering to the O. Eng. _haelend_ and the Ger. _Heiland_), is, with the fragments of a version of the story of Genesis believed to be by the same author, all that remains of the poetical literature of the old Saxons, i.e. the Saxons who continued in their original home. It contained when entire about 6000 lines, and portions of it are preserved in four MSS. The Cotton MS. in the British Museum, written probably late in the 10th century, is nearly complete, ending in the middle of the story of the journey to Emmaus. The Munich MS., formerly at Bamberg, begins at line 85, and has many lacunae, but continues the history down to the last verse of St Luke's Gospel, ending, however, in the middle of a sentence. A MS. discovered at Prague in 1881 contains lines 958-1106, and another, in the Vatican library, discovered by K. Zangemeister in 1894, contains lines 1279-1358. The poem is based, not directly on the New Testament, but on the pseudo-Tatian's harmony of the Gospels, and it shows acquaintance with the commentaries of Alcuin, Baeda and Hrabanus Maurus.

The questions relating to the _Heliand_ cannot be adequately discussed without considering also the poem on the history of Genesis, which, on the grounds of similarity in style and vocabulary, and for other reasons afterwards to be mentioned, may with some confidence be referred to the same author. A part of this poem, as is mentioned in the article CAEDMON, is extant only in an Old English translation. The portions that have been preserved in the original language are contained in the same Vatican MS. that includes the fragment of the _Heliand_ referred to above. In the one language or the other, there are in existence the following three fragments: (1) The passage which appears as lines 235-851 in the so-called "Caedmon's _Genesis_," on the revolt of the angels and the temptation and fall of Adam and Eve. Of this the part corresponding to lines 790-820 exists also in the original Old Saxon. (2) The story of Cain and Abel, in 124 lines. (3) The account of the destruction of Sodom, in 187 lines. The main source of the _Genesis_ is the Bible, but Professor E. Sievers has shown that considerable use was made of the two Latin poems by Alcimus Avitus, _De initio mundi_ and _De peccato originali_.

The two poems give evidence of genius and trained skill, though the poet was no doubt hampered by the necessity of not deviating too widely from the sacred originals. Within the limits imposed by the nature of his task, his treatment of his sources is remarkably free, the details unsuited for poetic handling being passed over, or, in some instances, boldly altered. In many passages his work gives the impression of being not so much an imitation of the ancient Germanic epic, as a genuine example of it, though concerned with the deeds of other heroes than those of Germanic tradition. In the _Heliand_ the Saviour and His Apostles are conceived as a king and his faithful warriors, and the use of the traditional epic phrases appears to be not, as with Cynewulf or the author of _Andreas_, a mere following of accepted models, but the spontaneous mode of expression of one accustomed to sing of heroic themes. The _Genesis_ fragments have less of the heroic tone, except in the splendid passage describing the rebellion of Satan and his host. It is noteworthy that the poet, like Milton, sees in Satan no mere personification of evil, but the fallen archangel, whose awful guilt could not obliterate all traces of his native majesty. Somewhat curiously, but very naturally, Enoch the son of Cain is confused with the Enoch who was translated to heaven--an error which the author of the Old English _Genesis_ avoids, though (according to the existing text) he confounds the names of Enoch and Enos.

Such external evidence as exists bearing on the origin of the _Heliand_ and the companion poem is contained in a Latin document printed by Flacius Illyricus in 1562. This is in two parts; the one in prose, entitled (perhaps only by Flacius himself) "_Praefatio ad librum antiquum in lingua Saxonica conscriptum_"; the other in verse, headed "_Versus de poeta et Interpreta hujus codicis_." The Praefatio begins by stating that the emperor Ludwig the Pious, desirous that his subjects should possess the word of God in their own tongue, commanded a certain Saxon, who was esteemed among his countrymen as an eminent poet, to translate poetically into the German language the Old and New Testaments. The poet willingly obeyed, all the more because he had previously received a divine command to undertake the task. He rendered into verse all the most important parts of the Bible with admirable skill, dividing his work into _vitteas_, a term which, the writer says, may be rendered by "_lectiones_" or "_sententias_." The Praefatio goes on to say that it was reported that the poet, till then knowing nothing of the art of poetry, had been admonished in a dream to turn into verse the precepts of the divine law, which he did with so much skill that his work surpasses in beauty all other German poetry (_ut cuncta Theudisca poemata suo vincat decore_). The _Versus_ practically reproduce in outline Baeda's account of Caedmon's dream, without mentioning the dream, but describing the poet as a herdsman, and adding that his poems, beginning with the creation, relate the history of the five ages of the world down to the coming of Christ.

The suspicion of some earlier scholars that the _Praefatio_ and the _Versus_ might be a modern forgery is refuted by the occurrence of the word _vitteas_, which is the Old Saxon _fittea_, corresponding to the Old English _fitt_, which means a "canto" of a poem. It is impossible that a scholar of the 16th century could have been acquainted with this word, and internal evidence shows clearly that both the prose and the verse are of early origin. The _Versus_, considered in themselves, might very well be supposed to relate to Caedmon; but the mention of the five ages of the world in the concluding lines is obviously due to recollection of the opening of the _Heliand_ (lines 46-47). It is therefore certain that the _Versus_, as well as the _Praefatio_, attribute to the author of the _Heliand_ a poetic rendering of the Old Testament. Their testimony, if accepted, confirms the ascription to him of the Genesis fragments, which is further supported by the fact that they occur in the same MS. with a portion of the _Heliand_. As the _Praefatio_ speaks of the emperor Ludwig in the present tense, the former part of it at least was probably written in his reign, i.e. not later than A.D. 840. The general opinion of scholars is that the latter part, which represents the poet as having received his vocation in a dream, is by a later hand, and that the sentences in the earlier part which refer to the dream are interpolations by this second author. The date of these additions, and of the _Versus_, is of no importance, as their statements are incredible. That the author of the _Heliand_ was, so to speak, another Caedmon--an unlearned man who turned into poetry what was read to him from the sacred writings--is impossible, because in many passages the text of the sources is so closely followed that it is clear that the poet wrote with the Latin books before him. On the other hand, there is no reason for rejecting the almost contemporary testimony of the first part of the _Praefatio_ that the author of the _Heliand_ had won renown as a poet before he undertook his great task at the emperor's command. It is certainly not impossible that a Christian Saxon, sufficiently educated to read Latin easily, may have chosen to follow the calling of a _scop_ or minstrel[1] instead of entering the priesthood or the cloister; and if such a person existed, it would be natural that he should be selected by the emperor to execute his design. As has been said above, the tone of many portions of the _Heliand_ is that of a man who was no mere imitator of the ancient epic, but who had himself been accustomed to sing of heroic themes.

The commentary on the gospel of Matthew by Hrabanus Maurus was finished about 821, which is therefore the superior limit of date for the composition of the _Heliand_. It is usually maintained that this work was written before the Old Testament poems. The arguments for this view are that the _Heliand_ contains no allusion to any foregoing poetical treatment of the antecedent history, and that the Genesis fragments exhibit a higher degree of poetic skill. This reasoning does not appear conclusive, and if it be set aside, the limit of date for the beginning of the work is carried back to A.D. 814, the year of the accession of Ludwig.

BIBLIOGRAPHY.--The first complete edition of the _Heliand_ was published by J. A. Schmeller in 1830; the second volume, containing the glossary and grammar, appeared in 1840. The standard edition is that of E. Sievers (1877), in which the texts of the Cotton and Munich MSS. are printed side by side. It is not provided with a glossary, but contains an elaborate and most valuable analysis of the diction, synonymy and syntactical features of the poem. Other useful editions are those of M. Heyne (3rd ed., 1903), O. Behaghel (1882) and P. Piper (1897, containing also the Genesis fragments). The fragments of the _Heliand_ and the _Genesis_ contained in the Vatican MS. were edited in 1894 by K. Zangemeister and W. Braune under the title _Bruchstucke der altsachsischen Bibeldichtung_. Among the works treating of the authorship, sources and place of origin of the poems, the most important are the following: E. Windisch, _Der Heliand und seine Quellen_ (1868); E. Sievers, _Der Heliand und die angelsachsische Genesis_ (1875); R. Kogel, _Deutsche Literaturgeschichte_, Bd. i. (1894) and _Die altsachsische Genesis_ (1895); R. Kogel and W. Bruckner, "Althoch- und altniederdeutsche Literatur," in Paul's _Grundriss der germanischen Philologie_, Bd. ii. (2nd ed., 1901), which contains references to many other works; Hermann Collitz, _Zum Dialekte des Heliand_ (1901). (H. Br.)

FOOTNOTE:

[1] The term _Volkssanger_, commonly used in German discussions of this question, is misleading; the audience for heroic poetry was not "the people" in the modern sense, but the nobles.

HELICON, a mountain range, of Boeotia in ancient Greece, celebrated in classical literature as the favourite haunt of the Muses, is situated between Lake Copais and the Gulf of Corinth. On the fertile eastern slopes stood a temple and grove sacred to the Muses, and adorned with beautiful statues, which, taken by Constantine the Great to beautify his new city, were consumed there by a fire in A.D. 404. Hard by were the famous fountains, Aganippe and Hippocrene, the latter fabled to have gushed from the earth at the tread of the winged horse Pegasus, whose favourite browsing place was there. At the neighbouring Ascra dwelt the poet Hesiod, a fact which probably enhanced the poetic fame of the region. Pausanias, who describes Helicon in his ninth book, asserts that it was the most fertile mountain in Greece, and that neither poisonous plant nor serpent was to be found on it, while many of its herbs possessed a miraculous healing virtue. The highest summit, the present Palaeovouni (old hill), rises to the height of about 5000 ft. Modern travellers, aided by ancient remains and inscriptions, and guided by the local descriptions of Pausanias, have succeeded in identifying many of the ancient classical spots, and the French excavators have discovered the temple of the Muses and a theatre.

See also Clarke, _Travels in Various Countries_ (vol. vii., 1818); Dodwell, _Classical and Topographical Tour through Greece_ (1818); W. M. Leake, _Travels in Northern Greece_ (vol. ii., 1835); J. G. Frazer's edition of _Pausanias_, v. 150.

HELICON (Fr. _helicon, bombardon circulaire_; Ger. _Helikon_), the circular form of the B[flat] contrabass tuba used in military bands, worn round the body, with the enormous bell resting on the left shoulder and towering above the head of the performer. The pitch of the helicon is an octave below that of the euphonium. The idea of winding the long tube of the contrabass tuba and of wearing it round the shoulders was suggested by the ancient Roman buccina and cornu, represented in mosaics and on the sculptured reliefs surrounding Trajan's Column. The buccina and cornu[1] differed in the diameter of their respective bores, the former having the narrow, almost cylindrical bore and harmonic series of the trumpet and trombone, whereas the cornu, having a bore in the form of a wide cone, was the prototype of the bugle and tubas.

FOOTNOTE:

[1] For illustrations of the cornu see the altar of Julius Victor ex Collegio, reproduced in Bartoli, Pict. Ant. p. 76; Bellori, _Pict. antiq. crypt. rom._ p. 76, pl. viii.; in Daremberg and Saglio, _Dict. des antiq. grecques et romaines_, under "Cornu," the buccina and cornu have not been distinguished.

HELIGOLAND (Ger. _Helgoland_), an island of Germany, in the North Sea, lying off the mouths of the Elbe and the Weser, 28 m. from the nearest point in the mainland. Pop. (1900) 2307. From 1807 to 1890 a British possession, it was ceded in 1890 to Germany, and since 1892 has formed part of the Prussian province of Schleswig-Holstein. It consists of two islets, the smaller, the Dunen-Insel, a quarter of a mile E. of the main, or Rock Island, connected until 1720, when it was severed by a violent irruption of the sea, with the other by a neck of land, and the main, or Rock Island. The latter is nearly triangular in shape and is surrounded by steep red cliffs, the only beach being the sandy spit near the south-east point, where the landing-stage is situated. The rocks composing the cliffs are worn into caves, and around the island are many fantastic arches and columns. The impression made by the red cliffs, fringed by a white beach and supporting the green Oberland, is commonly believed to have suggested the national colours, red, white and green, or, as the old Frisian rhyme goes:--

"Gron is dat Land, Rood is de Kant, Witt is de Sand, Dat is de Flagg vun't hillige Land."

The lower town of Unterland, on the spit, and the upper town, or Oberland, situated on the cliff above, are connected by a wooden stair and a lift. There is a powerful lighthouse, and since its cession by Great Britain to Germany, the main island has been strongly fortified, the old English batteries being replaced by armoured turrets mounting guns of heavy calibre. Inside the Dunen-Insel the largest ships can ride safely at anchor, and take in coal and other supplies. The greatest length of the main island, which slopes somewhat from west to east, is just a mile, and the greatest breadth less than a third of a mile, its average height 198 ft., and the highest point, crowned by the church, with a conspicuous spire, 216 ft. The Dunen-Insel is a sand-bank protected by groines. It is only about 200 ft. above the sea at its highest point, but the drifting sands make the height rather variable. The sea-bathing establishment is situated here; a shelving beach of white sand presenting excellent facilities for bathing. Most of the houses are built of brick, but some are of wood. There are a theatre, a Kurhaus, and a number of hotels and restaurants. In 1892 a biological institute, with a marine museum and aquarium (1900) attached, was opened.

During the summer some 20,000 people visit the island for sea-bathing. German is the official language, though among themselves the natives speak a dialect of Frisian, barely intelligible to the other islands of the group. There is regular communication with Bremen and Hamburg.

The winters are stormy. May and the early part of June are wet and foggy, so that few visitors arrive before the middle of the latter month.

The generally accepted derivation of Heligoland (or Helgoland) from _Heiligeland_, i.e. "Holy Land," seems doubtful. According to northern mythology, Forseti, a son of Balder and Nanna, the god of justice, had a temple on the island, which was subsequently destroyed by St Ludger. This legend may have given rise to the derivation "Holy Land." The more probable etymology, however, is that of Hallaglun, or Halligland, i.e. "land of banks, which cover and uncover." Here Hertha, according to tradition, had her great temple, and hither came from the mainland the Angles to worship at her shrine. Here also lived King Radbod, a pagan, and on this isle St Willibrord in the 7th century first preached Christianity; and for its ownership, before and after that date, many sea-rovers have fought. Finally it became a fief of the dukes of Schleswig-Holstein, though often hypothecated for loans advanced to these princes by the free city of Hamburg. The island was a Danish possession in 1807, when the English seized and held it until it was formally ceded to them in 1814. In the picturesque old church there are still traces of a painted Dannebrog.

In 1890 the island was ceded to Germany, and in 1892 it was incorporated with Prussia, when it was provided that natives born before the year 1880 should be allowed to elect either for British or German nationality, and until 1901 no additional import duties were imposed.

BIBLIOGRAPHY.--Von der Decken, _Philosophisch-historisch-geographische Untersuchungen uber die Insel Helgoland, oder Heiligeland, und ihre Bewohner_ (Hanover, 1826); Wiebel, _Die Insel Helgoland, Untersuchungen uber deren Grosse in Vorzeit und Gegenwart vom Standpunkte der Geschichte und Geologie_ (Hamburg, 1848); J. M. Lappenberg, _Uber den ehemaligen Umfang und die alte Geschichte Helgolands_ (Hamburg, 1831); F. Otker, _Helgoland. Schilderungen und Erorterungen_ (Berlin, 1855); E. Hallier, _Helgoland, Nordseestudien_ (Hamburg, 1893); A. W. F. Moller, _Rechtsgeschichte der Insel Helgoland_ (Weimar, 1904); W. G. Black, _Heligoland and the Islands of the North Sea_ (Glasgow, 1888); E. Lindermann, _Die Nordseeinsel Helgoland in topographischer, geschichtlicher, sanitarer Beziehung_ (Berlin, 1889); and Tittel, _Die naturlichen Veranderungen Helgolands_ (Leipzig, 1894).

HELIOCENTRIC, i.e. referred to the centre of the sun ([Greek: helios]) as an origin, a term designating especially co-ordinates or heavenly bodies referred to that origin.

HELIODORUS, of Emesa in Syria, Greek writer of romance. According to his own statement his father's name was Theodosius, and he belonged to a family of priests of the sun. He was the author of the _Aethiopica_, the oldest and best of the Greek romances that have come down to us. It was first brought to light in modern times in a MS. from the library of Matthias Corvinus, found at the sack of Buda (Ofen) in 1526, and printed at Basel in 1534. Other codices have since been discovered. The title is taken from the fact that the action of the beginning and end of the story takes place in Aethiopia. The daughter of Persine, wife of Hydaspes, king of Aethiopia, was born white through the effect of the sight of a marble statue upon the queen during pregnancy. Fearing an accusation of adultery, the mother gives the babe to the care of Sisimithras, a gymnosophist, who carries her to Egypt and places her in charge of Charicles, a Pythian priest. The child is taken to Delphi, and made a priestess of Apollo under the name of Chariclea. Theagenes, a noble Thessalian, comes to Delphi and the two fall in love with each other. He carries off the priestess with the help of Calasiris, an Egyptian, employed by Persine to seek for her daughter. Then follow many perils from sea-rovers and others, but the chief personages ultimately meet at Meroe at the very moment when Chariclea is about to be sacrificed to the gods by her own father. Her birth is made known, and the lovers are happily married. The rapid succession of events, the variety of the characters, the graphic descriptions of manners and of natural scenery, the simplicity and elegance of the style, give the _Aethiopica_ great charm. As a whole it offends less against good taste and morality than others of the same class. Homer and Euripides were the favourite authors of Heliodorus, who in his turn was imitated by French, Italian and Spanish writers. The early life of Clorinda in Tasso's _Jerusalem Delivered_ (canto xii. 21 sqq.) is almost identical with that of Chariclea; Racine meditated a drama on the same subject; and it formed the model of the _Persiles y Sigismunda_ of Cervantes. According to the ecclesiastical historian Socrates (_Hist. eccles._ v. 22), the author of the _Aethiopica_ was a certain Heliodorus, bishop of Tricca in Thessaly. It is supposed that the work was written in his early years before he became a Christian, and that, when confronted with the alternative of disowning it or resigning his bishopric, he preferred resignation. But it is now generally agreed that the real author was a sophist of the 3rd century A.D.

The best editions are: A. Coraes (1804), G. A. Hirschig (1856); see also M. Oeftering, _H. und seine Bedeutung fur die Literatur_, with full bibliographies (1901); J. C. Dunlop, _History of Prose Fiction_ (1888); and especially E. Rohde, _Der griechische Roman_ (1900). There are translations in almost all European languages: in English, in Bohn's _Classical Library_ and the "Tudor" series (v., 1895, containing the old translation by T. Underdowne, 1587, with introduction by C. Whibley); in French by Amyot and Zevort.

HELIOGABALUS (ELAGABALUS), Roman emperor (A.D. 218-222), was born at Emesa about 205. His real name was Varius Avitus. On the murder of Caracalla (217), Julia Maesa, Varius's grandmother and Caracalla's aunt, left Rome and retired to Emesa, accompanied by her grandsons (Varius and Alexander Severus). Varius, though still only a boy, was appointed high priest of the Syrian sun-god Elagabalus, one of the chief seats of whose worship was Emesa (Homs). His beauty, and the splendid ceremonials at which he presided, made him a great favourite with the troops stationed in that part of Syria, and Maesa increased his popularity by spreading reports that he was in reality the illegitimate son of Caracalla. Macrinus, the successor and instigator of the murder of Caracalla, was very unpopular with the army; an insurrection was easily set on foot, and on the 16th of May 218 Varius was proclaimed emperor as Marcus Aurelius Antoninus. The troops sent to quell the revolt went over to him, and Macrinus was defeated near Antioch on the 8th of June. Heliogabalus was at once recognized by the senate as emperor. After spending the winter in Nicomedia, he proceeded in 219 to Rome, where he made it his business to exalt the deity whose priest he was and whose name he assumed. The Syrian god was proclaimed the chief deity in Rome, and all other gods his servants; splendid ceremonies in his honour were celebrated, at which Heliogabalus danced in public, and it was believed that secret rites accompanied by human sacrifice were performed in his honour. In addition to these affronts upon the state religion, he insulted the intelligence of the community by horseplay of the wildest description and by childish practical joking. The shameless profligacy of the emperor's life was such as to shock even a Roman public. His popularity with the army declined, and Maesa, perceiving that the soldiers were in favour of Alexander Severus, persuaded Heliogabalus to raise his cousin to the dignity of Caesar (221), a step of which he soon repented. An attempt to murder Alexander was frustrated by the watchful Maesa. Another attempt in 222 produced a mutiny among the praetorians, in which Heliogabalus and his mother Soemias (Soaemias) were slain (probably in the first half of March).

AUTHORITIES.--Life by Aelius Lampridius in _Scriptores historiae Augustae_; Herodian v. 3-8; Dio Cassius lxxviii. 30 sqq., lxxix. 1-21; monograph by G. Duviquet, _Heliogabale_ (1903), containing a translation of the various accounts of Heliogabalus in Greek and Latin authors, notes, bibliography and illustrations; O. F. Butler, _Studies in the Life of Heliogabalus_ (New York, 1908); Gibbon, _Decline and Fall_, ch. 6; H. Schiller, _Geschichte der romischen Kaiserzeit_, i. pt. ii. (1883), p. 759 ff. On the Syrian god see F. Cumont in Pauly-Wissowa's _Realencyclopadie_, v. pt. ii. (1905).

HELIOGRAPH (from Gr. [Greek: elios], sun, and [Greek: graphein] to write), an instrument for reflecting the rays of the sun (or the light obtained from any other source) over a considerable distance. Its main application is in military signalling (see SIGNAL). A similar instrument is the heliotrope, used principally for defining distant points in geodetic surveys, such as in the triangulation of India, and in the verification of the African arc of the meridian. It is necessary to distinguish the method of signalling termed heliography from the photographic process of the same name (see PHOTOGRAPHY).

HELIOMETER (from Gr. [Greek: helios], sun, and [Greek: metron], a measure), an instrument originally designed for measuring the variation of the sun's diameter at different seasons of the year, but applied now to the modern form of the instrument which is capable of much wider use. The present article also deals with other forms of double-image micrometer.

The discovery of the method of making measures by double images is stated to have been first suggested by O. Roemer about 1768. But no such suggestion occurs in the _Basis Astronomiae_ of Peter Horrebow (Copenhagen, 1735), which contains the only works of Roemer that remain to us. It would appear that to Servington Savary is due the first invention of a micrometer for measurement by double image. His heliometer (described in a paper communicated to the Royal Society in 1743, and printed, along with a letter from James Short, in _Phil. Trans._, 1753, p. 156) was constructed by cutting from a complete lens abcd the equal portions aghc and acfe (fig. 1). The segments gbh and efd so formed were then attached to the end of a tube having an internal diameter represented by the dotted circle (fig. 2). The width of each of the portions aghc and acfe cut away from the lens was made slightly greater than the focal length of lens X tangent of sun's greatest diameter. Thus at the focus two images of the sun were formed nearly in contact as in fig. 3. The small interval between the adjacent limbs was then measured with a wire micrometer.

Savary also describes another form of heliometer, on the same principle, in which the segments aghc and acfe are utilized by cementing their edges gh and ef together (fig. 4), and covering all except the portion indicated by the unshaded circle. Savary expresses preference for this second plan, and makes the pertinent remark that in both these models "the rays of red light in the two solar images will be next to each other, which will render the sun's disk more easy to be observed than the violet ones." This he mentions "because the glasses in these two sorts are somewhat prismatical, but mostly those of the first model, which could therefore bear no great charge (magnifying power)."

A third model proposed by Savary consists of two complete lenses of equal focal length, mounted in cylinders side by side, and attached to a strong brass plate (fig. 5). Here, in order to fulfil the purposes of the previous models, the distance of the centres of the lenses from each other should only slightly exceed the tangent of sun's diameter X focal length of lenses. Savary dwells on the difficulty both of procuring lenses sufficiently equal in focus and of accurately adjusting and centring them.

In the _Mem. Acad. de Paris_ (1748), Pierre Bouguer describes an instrument which he calls a heliometer. Lalande in his _Astronomie_ (vol. ii. p. 639) mentions such a heliometer which had been in his possession from the year 1753, and of which he gives a representation on Plate XXVIII., fig. 186, of the same volume. Bouguer's heliometer was in fact similar to that of Savary's third model, with the important difference that, instead of both object-glasses being fixed, one of them is movable by a screw provided with a divided head. No auxiliary filar micrometer was required, as in Savary's heliometer, to measure the interval between the limbs of two adjacent images of the sun, it being only necessary to turn the screw with the divided head to change the distance between the object-glasses till the two images of the sun are in contact as in fig. 6. The differences of the readings of the screw, when converted into arc, afford the means of measuring the variations of the sun's apparent diameter.

On the 4th of April 1754 John Dollond communicated a paper to the Royal Society of London (_Phil. Trans._, vol. xlviii. p. 551) in which he shows that a micrometer can be much more easily constructed by dividing a single object-glass through its axis than by the employment of two object-glasses. He points out--(1) that a telescope with an object-glass so divided still produces a single image of any object to which it may be directed, provided that the optical centres of the segments are in coincidence (i.e. provided the segments retain the same relative positions to each other as before the glass was cut); (2) that if the segments are separated in any direction two images of the object viewed will be produced; (3) that the most convenient direction of separation for micrometric purposes is to slide these straight edges one along the other as the figure on the margin (fig. 7) represents them: "for thus they may be moved without suffering any false light to come in between them; and by this way of removing them the distance between their centres may be very conveniently measured, viz. by having a vernier's division fixed to the brass work that holds one segment, so as to slide along a scale on the plate to which the other part of the glass is fitted."

Dollond then points out three different types in which a glass so divided and mounted may be used as a micrometer:--

"1. It may be fixed at the end of a tube, of a suitable length to its focal distance, as an object-glass,--the other end of the tube having an eye-glass fitted as usual in astronomical telescopes.

"2. It may be applied to the end of a tube much shorter than its focal distance, by having another convex glass within the tube, to shorten the focal distance of that which is cut in two.

"3. It may be applied to the open end of a reflecting telescope, either of the Newtonian or the Cassegrain construction."

Dollond adds his opinion that the third type is "much the best and most convenient of the three"; yet it is the first type that has survived the test of time and experience, and which is in fact the modern heliometer. It must be remembered, however, that when Dollond expressed preference for this third type he had not then invented the achromatic object-glass.

Some excellent instruments of the second type were subsequently made by Dollond's eldest son Peter, in which for the "convex glass within the tube" was substituted an achromatic object-glass, and outside that a divided negative achromatic combination of long focus. In the fine example of this instrument at the Cape Observatory the movable negative lenses consist of segments of the shape gach and acfe (fig. 1) cut from a complete negative achromatic combination of 8(1/4) in. aperture and about 41 ft. focal length, composed of a double concave flint lens and a double convex crown. This was applied to an excellent achromatic telescope of 3(1/4) in. aperture and 42 in. focal length. In this instrument a considerable linear relative movement of the divided lens corresponds with a comparatively small separation of the double image, so that simple verniers reading to 1/1000 in. are sufficient for measurement.

With one of these instruments of somewhat smaller dimensions (telescope 2(1/2) in. aperture and 3(1/2) ft. focus), Franz von Paula Triesnecker made a series of measurements at the observatory of Vienna which has been reduced by Dr Wilhelm Schur of Strasburg (_Nova Acta der Ksl. Leop.-Carol. Deutschen Akademie der Natursforscher_, 1882, xlv. No. 3). The angle between the stars [zeta] and g Ursae maj. (708".55) was measured on four nights; the probable error of a measure on one night was [+-]0".44. Jupiter was measured on eleven nights in the months of June and July 1794; from these measures Schur derives the values 35".39 and 37".94 for the polar and equatorial diameter respectively, at mean distance, corresponding with a compression 1/14.44. These agree satisfactorily with the corresponding values 35".21, 37".60, 1/15.59 afterwards obtained by F. W. Bessel (_Konigsberger Beobachtungen_, xix. 102). From a series of measures of the angle between Jupiter's satellites and the planet, made in June and July 1794 and in August and September 1795, Schur finds the mass of Jupiter = 1/1048.55 [+-] 1.45, a result which accords well within the limits of its probable error with the received value of the mass derived from modern researches. The probable errors for the measures of one night are [+-]0".577, [+-]0".889, [+-]0".542, [+-]1".096, for Satellites I., II., III. and IV. respectively.

Considering the accuracy of these measures (an accuracy far surpassing that of any other contemporary observations), it is somewhat surprising that this form of micrometer was never systematically used in any sustained or important astronomical researches, although a number of instruments of the kind were made by Dollond. Probably the last example of its employment is an observation of the transit of Mercury (November 4, 1868) by Mann, at the Royal Observatory, Cape of Good Hope (_Monthly Notices R.A.S._ vol. xxix. p. 197-209). The most important part, however, which this type of instrument seems to have played in the history of astronomy arises from the fact that one of them was in the possession of Bessel at Konigsberg during the time when his new observatory there was being built. In 1812 Bessel measured with it the angle between the components of the double star 61 Cygni and observed the great comet of 1811. He also observed the eclipse of the sun on May 4, 1818. In the discussion of these observations (_Konigsberger Beobacht_, Abt. 5, p. iv.) he found that the index error of the scale changed systematically in different position angles by quantities which were independent of the direction of gravity relative to the position angle under measurement, but which depended solely on the direction of the measured position angle relative to a fixed radius of the object-glass. Bessel attributed this to non-homogeneity in the object-glass, and determined with great care the necessary corrections. But he was so delighted with the general performance of the instrument, with the sharpness of the images and the possibilities which a kindred construction offered for the measurement of considerable angles with micrometric accuracy, that he resolved, when he should have the choice of a new telescope for the observatory, to secure some form of heliometer.

Nor is it difficult to imagine the probable course of reasoning which led Bessel to select the model of his new heliometer. Why, he might ask, should he not select the simple form of Dollond's first type? Given the achromatic object-glass, why should not it be divided? This construction would give all the advantage of the younger Dollond's object-glass micrometer, and more than its sharpness of definition, without liability to the systematic errors which may be due to want of homogeneity of the object-glass; for the lenses will not be turned with respect to each other, but, in measurement, will always have the same relation in position angle to the line joining the objects under observation. It is true that the scale will require to be capable of being read with much greater accuracy than 1/1000th of an inch--for that, even in a telescope of 10 ft. focus, would correspond with 2" of arc. But, after all, this is no practical difficulty, for screws can be used to separate the lenses, and, by these screws, as in a Gascoigne micrometer, the separation of the lenses can be measured; or we can have scales for this purpose, read by microscopes, like the Troughton[1] circles of Piazzi or Pond, or those of the Carey circle, with almost any required accuracy.

Whether Bessel communicated such a course of reasoning to Fraunhofer, or whether that great artist arrived independently at like conclusions, we have been unable to ascertain with certainty. The fact remains that before 1820[2] Fraunhofer had completed one or more of the five heliometers (3 in. aperture and 39 in. focus) which have since become historical instruments. In 1824 the great Konigsberg heliometer was commenced, and it was completed in 1829.

To sum up briefly the history of the development of the heliometer. The first application of the divided object-glass and the employment of double images in astronomical measures is due to Savary in 1743. To Bouguer in 1748 is due the true conception of measurement by double image without the auxiliary aid of a filar micrometer, viz. by changing the distance between two object-glasses of equal focus. To Dollond in 1754 we owe the combination of Savary's idea of the divided object-glass with Bouguer's method of measurement, and the construction of the first really practical heliometers. To Fraunhofer, some time not long previous to 1820, is due, so far as we can ascertain, the construction of the first heliometer with an achromatic divided object-glass, i.e. the first heliometer of the modern type.

_The Modern Heliometer._

The Konigsberg heliometer is represented in fig. 8. No part of the equatorial mounting is shown in the figure, as it resembles in every respect the usual Fraunhofer mounting. An adapter h is fixed on a telescope-tube, made of wood, in Fraunhofer's usual fashion. To this adapter is attached a flat circular flange h. The slides carrying the segments of the divided object-glass are mounted on a plate, which is fitted and ground to rotate smoothly on the flange h. Rotation is communicated by a pinion, turned by the handle c (concealed in the figure), which works in teeth cut on the edge of the flange h. The counterpoise w balances the head about its axis of rotation. The slides are moved by the screws a and b, the divided heads of which serve to measure the separation of the segments. These screws are turned from the eye-end by bevelled wheels and pinions, the latter connected with the handles a', b'. The reading micrometers e, f also serve to measure, independently, the separation of the segments, by scales attached to the slides; such measurements can be employed as a check on those made by the screws. The measurement of position angles is provided for by a graduated circle attached to the head. There is also a position circle, attached at m to the eye-end, provided with a slide to move the eye-piece radially from the axis of the telescope, and with a micrometer to measure the distance of an object from that axis. The ring c, which carries the supports of the handles a', b', is capable of a certain amount of rotation on the tube. The weight of the handles and their supports is balanced by the counterpoise z. This ring is necessary in order to allow the rods to follow the micrometer heads when the position angle is changed. Complete rotation of the head is obviously impossible because of the interference of the declination axis with the rods, and therefore, in some angles, objects cannot be measured in two positions of the circle. The object-glass has an aperture of 6(1/2) in. and 102 in. focal length.

There are three methods in which this heliometer can be used.

_First Method._--One of the segments is fixed in the axis of the telescope, and the eye-piece is also placed in the axis. Measures are made with the moving segment displaced alternately on opposite sides of the fixed segment.

_Second Method._--One segment is fixed, and the measures are made as in the first method, excepting that the eye-piece is placed symmetrically with respect to the images under measurement. For this purpose the position angle of the eye-piece micrometer is set to that of the head, and the eye-piece is displaced from the axis of the tube (in the direction of the movable segment) by an amount equal to half the angle under measurement.

_Third Method._--The eye-piece is fixed in the axis, and the segments are symmetrically displaced from the axis each by an amount equal to half the angle measured.

Of these methods Bessel generally employed the first because of its simplicity, notwithstanding that it involved a resetting of the right ascension and declination of the axis of the tube with each reversal of the segments. The chief objections to the method are that, as one star is in the axis of the telescope and the other displaced from it, the images are not both in focus of the eye-piece,[3] and the rays from the two stars do not make the same angle with the optical axis of each segment. Thus the two images under measurement are not defined with equal sharpness and symmetry. The second method is free from the objection of non-coincidence in focus of the images, but is more troublesome in practice from the necessity for frequent readjustment of the position of the eye-piece. The third method is the most symmetrical of all, both in observation and reduction; but it was not employed by Bessel, on the ground that it involved the determination of the errors of two screws instead of one. On the other hand it is not necessary to reset the telescope after each reversal of the segments.[4]

When Bessel ordered the Konigsberg heliometer, he was anxious to have the segments made to move in cylindrical slides, of which the radius should be equal to the focal length of the object-glass. Fraunhofer, however, did not execute this wish, on the ground that the mechanical difficulties were too great.

M. L. G. Wichmann states (_Konigsb. Beobach._ xxx. 4) that Bessel had indicated, by notes in his handbooks, the following points which should be kept in mind in the construction of future heliometers: (1) The segments should move in cylindrical slides;[5] (2) the screw should be protected from dust;[6] (3) the zero of the position circle should not be so liable to change;[7] (4) the distance of the optical centres of the segments should not change in different position angles or otherwise;[8] (5) the points of the micrometer screws should rest on ivory plates;[9] (6) there should be an apparatus for changing the screen.[10]

Wilhelm Struve, in describing the Pulkowa heliometer,[11] made by Merz in 1839 on the model of Bessel's heliometer, submits the following suggestions for its improvement:[12] (1) to give automatically to the two segments simultaneous equal and opposite movement;[13] and (2) to make the tube of metal instead of wood; to attach the heliometer head firmly to this tube; to place the eye-piece permanently in the axis of the telescope; and to fix a strong cradle on the end of the declination axis, in which the tube, with the attached head and eye-piece, could rotate on its axis.

Both suggestions are important. The first is originally the idea of Dollond; its advantages were overlooked by his son, and it seems to have been quite forgotten till resuggested by Struve. But the method is not available if the separation is to be measured by screws; it is found, in that case, that the direction of the final motion of turning of the screw must always be such as to produce motion of the segment against gravity, otherwise the "loss of time" is apt to be variable. Thus the simple connexion of the two screws by cog-wheels to give them automatic opposite motion is not an available method unless the separation of the segments is independently measured by scales.

Struve's second suggestion has been adopted in nearly all succeeding heliometers. It permits complete rotation of the tube and measurement of all angles in reversed positions of the circle; the handles that move the slides can be brought down to the eye-end, inside the tube, and consequently made to rotate with it; and the position circle may be placed at the end of the cradle next the eye-end where it is convenient of access. Struve also points out that by attaching a fine scale to the focusing slide of the eye-piece, and knowing the coefficient of expansion of the metal tube, the means would be provided for determining the absolute change of the focal length of the object-glass at any time by the simple process of focusing on a double star. This, with a knowledge of the temperature of the screw or scale and its coefficient of expansion, would enable the change of screw-value to be determined at any instant.

It is probable that the Bonn heliometer was in course of construction before these suggestions of Struve were published or discussed, since its construction resembles that of the Konigsberg and Pulkowa instruments. Its dimensions are similar to those of the former instrument. Bessel, having been consulted by the celebrated statesman, Sir Robert Peel, on behalf of the Radcliffe trustees, as to what instrument, added to the Radcliffe Observatory, would probably most promote the advancement of astronomy, strongly advised the selection of a heliometer. The order for the instrument was given to the Repsolds in 1840, but "various circumstances, for which the makers are not responsible, contributed to delay the completion of the instrument, which was not delivered before the winter of 1848."[14] The building to receive it was commenced in March 1849 and completed in the end of the same year. This instrument has a superb object-glass of 7(1/2) in. aperture and 126 in. focal length. The makers availed themselves of Bessel's suggestion to make the segments move in cylindrical slides, and of Struve's to have the head attached to a brass tube; the eye-piece is set permanently in the axis, and the whole rotates in a cradle attached to the declination axis. They provided a splendid, rigidly mounted, equatorial stand, fitted with every luxury in the way of slow motion, and scales for measuring the displacement of the segments were read by powerful micrometers from the eye-end.[15] It is somewhat curious that, though Struve's second suggestion was adopted, his first was overlooked by the makers. But it is still more curious that it was not afterwards carried out, for the communication of automatic symmetrical motion to both segments only involves a simple alteration previously described. But, as it came from the hands of the makers in 1849, the Oxford heliometer was incomparably the most powerful and perfect instrument in the world for the highest order of micrometric research. It so remained, unrivalled in every respect, till 1873.

As the transit of Venus of 1874 approached, preparations were set on foot by the German Government in good time; a commission of the most celebrated astronomers was appointed, and it was resolved that the heliometer should be the instrument chiefly relied on. The four long-neglected small heliometers made by Fraunhofer were brought into requisition. Fundamental alterations were made upon them: their wooden tubes were replaced by tubes of metal; means of measuring the focal point were provided; symmetrical motion was given to the slides; scales on each slide were provided instead of screws for measuring the separation of the segments, and both scales were read by the same micrometer microscope; a metallic thermometer was added to determine the temperature of the scales. These small instruments have since done admirable work in the hands of Schur, Hartwig, Kustner, Elkin, Auwers and others.

The Russian Government ordered three new heliometers (each of 4 in. aperture and 5 ft. focal length) from the Repsolds, and the design for their construction was superintended by Struve, Auwers and Winnecke, the last-named making the necessary experiments at Carlsruhe. Fig. 9 represents the resulting type of instrument which was finally designed and constructed by Repsolds. The brass tube, strengthened at the bearing points by strong truly turned collars, rotates in the cast iron cradle q attached to the declination axis, a is the eye-piece fixed in the optical axis, b the micrometer for reading both scales, c and d are telescopes for reading the position circle p, e the handle for quick motion in position angle, f the slow motion in position angle, g the handle for changing the separation of the segments by acting on the bevel-wheel g' (fig. 10). h is a milled head connected by a rod with h' (fig. 10), for the purpose of interposing at pleasure the prism [pi] in the axis of the reading micrometer; this enables the observer to view the graduations on the face of the metallic thermometer [tau tau] (composed of a rod of brass and a rod of zinc), i is a milled head connected with the wheel i'i' (fig. 10), and affords the means of placing the screen s (fig. 9), counterpoised by w over either half of the object-glass. k clamps the telescope in declination, n clamps it in right ascension, and the handles m and l provide slow motion in declination and right ascension respectively.

The details of the interior mechanism of the "head" will be almost evident from fig. 10 without description. The screw, turned by the wheels at g', acts in a toothed arc, whence, as shown in the figure, equal and opposite motion is communicated to the slides by the jointed rods v, v. The slides are kept firmly down to their bearings by the rollers r, r, r, r, attached to axes which are, in the middle, very strong springs. Side-shake is prevented by the screws and pieces k, k, k, k. The scales are at n, n; they are fastened only at the middle, and are kept down by the brass pieces t, t.

A similar heliometer was made by the Repsolds to the order of Lord Lindsay for his Mauritius expedition in 1874. It differed only from the three Russian instruments in having a mounting by the Cookes in which the declination circle reads from the eye-end.[16] This instrument was afterwards most generously lent by Lord Lindsay to Gill for his expedition to Ascension in 1877.[17]

These four Repsold heliometers proved to be excellent instruments, easy and convenient in use, and yielding results of very high accuracy in measuring distances. Their slow motion in position angle, however, was not all that could be desired. When small movements were communicated to the handle e (fig. 9) by the tangent screw f, acting on a small toothed wheel clamped to the rod connected with the driving pinion, there was apt to be a torsion of the rod rather than an immediate action. Thus the slow motion would take place by jerks instead of with the necessary smoothness and certainty. When the heliometer-part of Lord Lindsay's heliometer was acquired by Gill in 1879, he changed the manner of imparting the motion in question. A square toothed racked wheel was applied to the tube at r (fig. 9). This wheel is acted on by a tangent screw whose bearings are attached to the cradle; the screw is turned by means of a handle supported by bearings attached to the cradle, and coming within convenient reach of the observer's hand. The tube turns smoothly in the racked wheel, or can be clamped to it at the will of the observer. This alteration and the new equatorial mounting have been admirably made by Grubb; the result is completely successful. The instrument so altered was in use at the Cape Observatory from March 1881 till 1887 in determining the parallax of some of the more interesting southern stars. The instrument then passed, by purchase from Gill, to Lord McLaren, by whom it was presented to the Royal Observatory, Edinburgh.

Still more recently the Repsolds have completed a new heliometer for Yale College, New Haven, United States. The object-glass is of 6 in. aperture and 98 in. focal length. The mounting, the tube, objective-cell, slides, &c., are all of steel.[18] The instrument is shown in fig. 11. The circles for position angle and declination are read by micrometer-microscopes illuminated by the lamp L; the scales are illuminated by the lamp l. T is part of the tube proper, and turns with the head. The tube V, on the contrary, is attached to the cradle, and merely forms a support for the finder Q, the handles at f and p, and the moving ring P. The latter gives quick motion in position angle; the handles at p clamp and give slow motion in position angle, those at f clamp and give slow motion in right ascension and declination. a is the eye-piece, b the handle for moving the segments, c the micrometer microscope for reading the scales and scale micrometer, d the micrometer readers of the position and declination circles, e the handle for rotating the large wheel E which carries the screens. The hour circle is also read by microscopes, and the instrument can be used in both positions (tube preceding and following) for elimination of the effect of flexure on the position angles. Elkin found that the chief drawbacks to speed and convenience in working this heliometer were: (1) The loss of time involved in entering the corresponding readings of the micrometer pointings on two scales. (2) That an additional motion intermediate between the quick and slow motion in position angle was necessary, because, whilst the slow motion provided by Repsolds was admirably adapted for adjusting the pointings in position angle, it was too slow for causing the images to "cross through" each other in the process of measuring distances. To remedy drawback (1) Repsolds devised the form of printing micrometer which is shown in figs. 12 and 13. This micrometer is provided with two pairs of parallel webs. One fixed pair of webs is attached to the micrometer-box, the other pair is moved by the screw S. The whole micrometer-box is moved by the screw attached to the heads. Accordingly, in reading the scales A and B (attached to the slides which carry the two halves of the object-glass), it is only necessary to turn the screws until the fixed double web is pointed symmetrically on one of the divisions of scale A, then to move the other double web by the screw S until it is symmetrically pointed on the adjoining division of scale B. By turning the quick acting screw P (fig. 13) to the right, the cushion C (which is faced with india-rubber) presses the paper ribbon (shown in fig. 13) against the index-edge and type-wheels, and thus the beautifully cut divisions of the micrometer-head, the numbers marking the 1/100 parts of the head, the index and the total number of revolutions are all sharply embossed together upon the paper ribbon. Fig. 14 shows the record of several successive paintings on the same scale as that given by the micrometer. The reverse motion of P automatically moves the paper ribbon forward, ready to receive the next impression. It must be mentioned that the pressure of the cushion C on the type-wheels has no influence whatever upon the micrometer-screw, because the type-wheels are mounted on a hollow cylindrical axis, concentric with the axis of the screw, but entirely disconnected from the screw itself. The only connexion between the type-wheel and the screw-head S is by the pin p (which is screwed into S), the cylindrical end of which acts in a slot cut in the type-wheel. To remedy drawback (2) Repsolds provided for the Yale heliometer an additional handle for motion in position angle, intermediate in velocity between the original quick and slow motions.

In the 7-in. heliometer, completed in 1887 for the Royal Observatory at the Cape of Good Hope, Repsolds, on Gill's suggestion, introduced the following improvements: (a) Four different speeds of motion in position angle were provided. The quickest movement is given by the hand-ring, 73 (fig. 15). This ring runs between friction wheels and is provided with teeth on its inner periphery, and these teeth transmit motion to a pinion on a spindle having at its other end another pinion which, through an intermediate wheel, rotates the heliometer tube. The transmission spindle, just mentioned, carries at its end a head, 74, which, if turned directly, gives the second speed. The slowest speed is given by means of a tangent screw which is carried by a ball-bearing on the flange of the telescope-sleeve, whilst its nut is double-jointed to a ring that encircles the flange of the heliometer-tube. This ring is provided with a clamping screw, which, through the intervention of bevel-gear and rods, is operated by means of the hand-wheel 78. With similar bevel-gear and rods the tangent screw is connected to the hand-wheel, 79, by which the observer communicates the fourth or slowest motion in position angle. Finally the hand-wheel 80 is connected by gearing to the rod carrying the hand-wheel 79, and it can thus be used to give the latter a more rapid motion than if used direct; this constitutes the third speed of movement.

(b) In lieu of oil-lamps, small, conveniently placed incandescent electric 6-volt lamps are employed; and these are fitted with suitable switches and variable resistances. Thus the scales, the position- and declination-circles, the field of view, the heads of all the micrometer-microscopes, the focusing scale, &c., are read without the aid of a hand-lamp and with an amount of illumination that can be regulated at the observer's pleasure.

(c) A button in the centre of the position-angle handle (74) connects with a chronograph which enables the observer to record the instant of observation. Little card-holders (81) (also illuminated) enable the astronomer to enter beforehand the R.A. and Dec. of the object to be observed, the scale divisions to be pointed upon, and thus, in measures of distance, with the aid of the chronograph and printing micrometer, enable the observer to adjust the instrument for observation and obtain a record of his observations without the aid of a hand-lamp or the necessity to make any records in his notebook. In observations of position angle one of the two tablets 81 can be used to record the readings.

(d) The scales are made of iridio-platinum instead of silver, and the magnifying power of the reading microscope is increased fourfold (viz. to 100 diameters). A special microscope is introduced for determining the division errors of the scales. It enables the observer to compare any division-interval on one half of either scale with any corresponding interval on the other scale. With this apparatus Gill was enabled (_Annals Cape Obs._ vii. 29-42, and _Monthly Notices, R.A.S._, xlix. 105-115) to determine the division error of every line on both scales with a probable error corresponding to [+-]0".0092 arc.

(e) A position-micrometer is attached to the finder to enable the observer to select comparison stars for observation with some unexpected object. Thus a comet may be encountered in the morning dawn or evening twilight, and without such an adjunct the astronomer may lose the whole available opportunity for observation in the vain endeavour to find a suitable comparison-star. But with such a position-micrometer of large field he has no difficulty. Directing the finder to the comet, he has at once in the field of view all available comparison stars. Having selected the most suitable one he directs the axis of the finder to the estimated middle point between the comet and the star, turns the finder-micrometer in position angle until the images of comet and star lie symmetrically between the parallel position wires, and then turns the micrometer screw (which moves the distance-wires symmetrically from the centre in opposite directions) till one wire bisects the comet and the other the star. The reading of the position-circle of the finder is then the reading to which the position-circle of the heliometer should be set, and from the readings of the micrometer-screw he finds, by a convenient table, the proper settings of the heliometer scales in distance. When the scales and position-circle of the heliometer have been set to these readings, the comet and the selected comparison-star appear together in the field of view.

Fig. 15 shows the very convenient arrangement of the eye-end of the instrument. The disk, 30 with its small projecting handle enables the 2 segments of the divided object to be moved rapidly or with any required delicacy relative to each other. The disk 32 operates the wire gauze screens for equalizing the brightness of the two stars under observation. The dial between 30 and 32 indicates the screen in use. 18 clamps and 19 gives slow motion in declination; 20 clamps and 21 gives slow motion in right ascension. The two handles 82 serve for manipulating the instrument. The microscopes adjoining 82 read the position and declination circles; for, by an ingenious arrangement of prisms and screens, the images of both circles can be read by each single microscope as shown in fig. 16, thus avoiding the necessity for the employment of two additional micrometers.

Experience has shown that there is little that can be advantageously changed to improve this instrument either in convenience or precision of working. A series of observations can be easily and more accurately accomplished with the Cape heliometer in half an hour; with the Oxford heliometer it would occupy 2 hours, and with the 4 in. Repsold heliometer (fig. 9) 1 hour. Heliometers of 6 to 8 in. aperture have subsequently been constructed by Repsolds on these plans for Gottingen, Bamberg, Leipzig and the Kuffner Observatory (near Vienna), and all of them have made important contributions to astronomy of precision.

Heliometer observations of distance in their most refined sense cannot be considered absolute measures of angles. Essentially the scale-value of the instrument depends on the relation of the focal length of the object-glass to the length of the unit of the scale. But _the eye is tolerant of small changes in the focal adjustment which sensibly affect the scale-value_. These changes may and do arise from the following causes: (i.) The focal length of the object-glass and the length of the tube are affected by temperature. (ii.) The focal length is sensibly different for objects of different colour. (iii.) The length of the scale is affected by temperature. (iv.) The state of adaptation of the observer's eye is dependent on his state of health, on a condition of greater or less fatigue, or on the inclination of the head in consequence of the altitude of the object observed. (v.) The temperature of the object-glass, of the scale and of the tube, cannot be assumed to be identical.

Thus, for refined purposes, it cannot be assumed with any certainty that the instantaneous scale-value of the heliometer is known, or that it is a function of the temperature. Of course, for many purposes, mean conditions may be adopted and mean scale-values be found which are applicable with considerable precision to small angles or to comparatively crude observations of large distances; but the highest refinement is lost unless means are provided for determining the scale-value for each observer at each epoch of observation.

In determinations of stellar or solar parallax, comparison stars, symmetrically situated with respect to the object whose parallax is sought, should be employed, in which case the instantaneous scale-value may be regarded as an unknown quantity which can be derived in the process of the computation of the results. Examples of this mode of procedure will be found, in the case of stellar parallax in the _Mem. R.A.S._ vol. xlviii. pp. 1-194, and in the _Annals of the Cape Observatory_, vol. viii. parts 1 and 2; and in the case of planetary parallax in the _Mem. R.A.S._ vol. xlvi. pp. 1-171, and in the _Annals of the Cape Observatory_, vol. vi. In other operations, such as the triangulation of large groups of stars, it is necessary to select a pair of standard stars, if possible near the middle of the group, and to determine the scale-value by measures of this standard distance at frequent intervals during the night (see _Annals of the Cape Observatory_, vol. vi. pp. 3-224). In other cases, such as the measurement of the mutual distances and position angles of the satellites of Jupiter, for derivation of the elements of the orbits of the satellites and the mass of Jupiter, reference must also be made to measures of standard stars whose relative distance and position angle is accurately determined by independent methods (see _Annals of the Cape Observatory_, vol. xii. part 2).

Gill introduced a powerful auxiliary to the accuracy of heliometer measures in the shape of a reversing prism placed in front of the eye-piece, between the latter and the observer's eye. If measures are made by placing the image of a star in the centre of the disk of a planet, the observer may have a tendency to do so systematically in error from some acquired habit or from natural astigmatism of the eye. But by rotating the prism 90 deg. the image is presented entirely reversed to the eye, so that in the mean of measures made in two such positions personal error is eliminated. Similarly the prism may be used for the study and elimination of personal errors depending on the angle made by a double star with the vertical. The best plan of mounting such a prism has been found to be the following. l^1, l^2 (fig. 17) are the eye lens and field lens respectively of a Merz positive eye-piece. In this construction the lenses are much closer together and the diaphragm for the eye is much farther from the lenses than in Ramsden's eye-piece. The prism p is fitted accurately into brass slides (care has to be taken in the construction to place the prism so that an object in the centre of the field will so remain when the eye-piece is rotated in its adapter). There is a collar, clamped by the screw at S, which is so adjusted that the eye-piece is in focus when pushed home, in its adapter, to this collar. The prism and eye-piece are then rotated together in the adapter.

_The Double Image Micrometer._--Thomas Clausen in 1841 (_Ast. Nach._ No. 414) proposed a form of micrometer consisting of a divided plate of parallel glass placed within the cone of rays from the object-glass at right angles to the telescope axis. One-half of this plane remains fixed, the other half is movable. When the inclination of the movable half with respect to the axis of the telescope is changed by rotation about an axis at right angles to the plane of division, two images are produced. The amount of separation is very small, and depends on the thickness of the glass, the index of refraction and the focal length of the telescope. Angelo Secchi (_Comptes rendus_, xli., 1855, p. 906) gives an account of some experiments with a similar micrometer; and Ignarjio Porro (_Comptes rendus_, xli. p. 1058) claims the original invention and construction of such a micrometer in 1842. Clausen, however, has undoubted priority. Helmholtz in his "Ophthalmometer" has employed Clausen's principle, but arranges the plates so that both move symmetrically in opposite directions with respect to the telescope axis. Should Clausen's micrometer be employed as an astronomical instrument, it would be well to adopt the improvement of Helmholtz.

_Double-Image Micrometers with Divided Lenses._--Various micrometers have been invented besides the heliometer for measuring by double image. Ramsden's dioptric micrometer consists of a divided lens placed in the conjugate focus of the innermost lens of the erecting eye-tube of a terrestrial telescope. The inventor claimed that it would supersede the heliometer, but it has never done anything for astronomy. Dollond claims the independent invention and first construction of a similar instrument (Pearson's _Practical Astronomy_, ii. 182). Of these and kindred instruments only two types have proved of practical value. G. B. Amici of Modena (_Mem. Soc. Ital._ xvii., 1815, pp. 344-359) describes a micrometer in which a negative lens is introduced between the eye-piece and the object-glass. This lens is divided and mounted like a heliometer object-glass; the separation of the lenses produces the required double image, and is measured by a screw. W. R. Dawes very successfully used this micrometer in conjunction with a filar micrometer, and found that the precision of the measures was in this way greatly increased (_Monthly Notices_, vol. xviii. p. 58, and _Mem. R.A.S._ vol. xxxv. p. 147).

In the improved form[19] of Airy's divided eye-glass micrometer (_Mem. R.A.S._ vol. xv. pp. 199-209) the rays from the object-glass pass successively through lenses as follows:

+-----------------------------------+---------------+---------------+ | Lens. | Distance from | Focal Length. | | | next Lens. | | +-----------------------------------+---------------+---------------+ | a. An equiconvex lens | p | arbitrary = p | | b. " " | 2 | 5 | | c. Plano-convex, convex towards b | 1(3/4) | 1 | | d. Plano-convex, convex towards c | " | 1 | +-----------------------------------+---------------+---------------+

The lens b is divided, and one of the segments is moved by a micrometer screw. The magnifying power is varied by changing the lens a for another in which p has a different value. The magnifying power of the eye-piece is that of a single lens of focus = 4/5p.

In 1850 J. B. Valz pointed out that the other optical conditions could be equally satisfied if the divided lens were made concave instead of convex, with the advantage of giving a larger field of view (_Monthly Notices_, vol. x. p. 160).

The last improvement on this instrument is mentioned in the _Report_ of the R.A.S. council, February 1865. It consists in the introduction by Simms of a fifth lens, but no satisfactory description has ever appeared. There is only one practical published investigation of Airy's micrometer that is worthy of mention, viz. that of F. Kaiser (_Annalen der Sternwarte in Leiden_, iii. 111-274). The reader is referred to that paper for an exhaustive history and discussion of the instrument.[20] It is somewhat surprising that, after Kaiser's investigations, observers should continue, as many have done, to discuss their observations with this instrument as if the screw-value were constant for all angles.

Steinheil (_Journal savant de Munich_, Feb. 28, 1843) describes a "heliometre-oculaire" which he made for the great Pulkowa refractor, the result of consultations between himself and the elder Struve. It is essentially the same in principle as Amici's micrometer, except that the divided lens is an achromatic positive instead of a negative lens. Struve (_Description de l'Observatoire Central de Pulkowa_, pp. 196, 197) adds a few remarks to Steinheil's description, in which he states that the images have not all desirable precision--a fault perhaps inevitable in all micrometers with divided lenses, and which is probably in this case aggravated by the fact that the rays falling upon the divided lens have considerable convergence. He, however, successfully employed the instrument in measuring double stars, so close as 1" or 2", and using a power of 300 diameters, with results that agreed satisfactorily amongst themselves and with those obtained with the filar micrometer. If Struve had employed a properly proportioned double circular diaphragm, fixed symmetrically with the axis of the telescope in front of the divided lens and turning with the micrometer, it is probable that his report on the instrument would have been still more favourable. This particular instrument has historical interest, having led Struve to some of those criticisms of the Pulkowa heliometer which ultimately bore such valuable fruit (see _ante_).

Ramsden (_Phil. Trans._ vol. xix. p. 419) suggested the division of the small speculum of a Cassegrain telescope and the production of double image by micrometric rotation of the semispecula in the plane passing through their axis. Brewster (_Ency. Brit._ 8th ed. vol. xiv. p. 749) proposed a plan on a like principle, by dividing the plane mirror of a Newtonian telescope. Again, in an ocular heliometer by Steinheil double image is similarly produced by a divided prism of total reflection placed in parallel rays. But practically these last three methods are failures. In the last the field is full of false light, and it is not possible to give sufficiently minute and steady separation to the images; and there are of necessity a collimator, two prisms of total reflection, and a small telescope through which the rays must pass; consequently there is great loss of light.

_Micrometers Depending on Double Refraction._--To the Abbe Rochon (_Jour. de phys._ liii., 1801, pp. 169-198) is due the happy idea of applying the two images formed by double refraction to the construction of a micrometer. He fell upon a most ingenious plan of doubling the amount of double refraction of a prism by using two prisms of rock-crystal, so cut out of the solid as to give each the same quantity of double refraction, and yet to double the quantity in the effect produced. The combination so formed is known as Rochon's prism. Such a prism he placed between the object-glass and eye-piece of a telescope. The separation of the images increases as the prism is approached to the object-glass, and diminishes as it is approached towards the eye-piece.

D. F. J. Arago (_Comptes rendus_, xxiv., 1847, pp. 400-402) found that in Rochon's micrometer, when the prism was approached close to the eye-piece for the measurement of very small angles, the smallest imperfections in the crystal or its surfaces were inconveniently magnified. He therefore selected for any particular measurement such a Rochon prism as when fixed between the eye and the eye-piece (i.e. where a sunshade is usually placed) would, combined with the normal eye-piece employed, bring the images about to be measured nearly in contact. He then altered the magnifying power by sliding the field lens of the eye-piece (which was fitted with a slipping tube for the purpose) along the eye-tube, till the images were brought into contact. By a scale attached to the sliding tube the magnifying power of the eye-piece was deduced, and this combined with the angle of the prism employed gave the angle measured. If p" is the refracting angle of the prism, and n the magnifying power of the eye-piece, then p"/n will be the distance observed. Arago made many measures of the diameters of the planets with such a micrometer.

Dollond (_Phil. Trans._, 1821, pp. 101-103) describes a double-image micrometer of his own invention, in which a sphere of rock-crystal is substituted for the eye-lens of an ordinary eye-piece. In this instrument (figs. 18, 19) a is the sphere, placed in half-holes on the axis bb, so that when its principal axis is parallel to the axis of the telescope it gives only one image of the object. In a direction perpendicular to that axis it must be so placed that when it is moved by rotation of the axis bb the separation of the images shall be parallel to that motion. The angle of rotation is measured on the graduated circle C. The angle between the objects measured is = r sin 2[theta], where r is a constant to be determined for each magnifying power employed,[21] and [theta] the angle through which the sphere has been turned from zero (i.e. from coincidence of its principal axis with that of the telescope). The maximum separation is consequently at 45 deg. from zero. The measures can be made on both sides of zero for eliminating index error. There are considerable difficulties of construction, but these have been successfully overcome by Dollond; and in the hands of Dawes (_Mem. R.A.S._ xxxv. p. 144 seq.) such instruments have done valuable service. They are liable to the objection that their employment is limited to the measurement of very small angles, viz. 13" or 14" when the magnifying power is 100, and varying inversely as the power. Yet the beautiful images which these micrometers give permit the measurement of very difficult objects as a check on measures with the parallel-wire micrometer.

On the theory of the heliometer and its use consult Bessel, _Astronomische Untersuchungen_, vol. i.; Hansen, _Ausfuhrliche Methode mit dem Fraunhoferschen Heliometer anzustellen_ (Gotha, 1827); Chauvenet, _Spherical and Practical Astronomy_, vol. ii. (Philadelphia and London, 1876); Seeliger, _Theorie des Heliometers_ (Leipzig, 1877); Lindsay and Gill, _Dunecht Publications_, vol. ii. (Dunecht, for private circulation, 1877); Gill, _Mem. R.A.S._ vol. xlvi. pp. 1-172, and references mentioned in the text. (D. Gi.)

FOOTNOTES:

[1] The circles by Reichenbach, then almost exclusively used in Germany, were read by verniers only.

[2] The diameter of Venus was measured with one of these heliometers at the observatory of Breslau by Brandes in 1820 (_Berlin Jahrbuch_, 1824, p. 164).

[3] The distances of the optical centres of the segments from the eye-piece are in this method as 1; secant of the angle under measurement. In Bessel's heliometer this would amount to a difference of 15/1000th of an inch when an angle of 1 deg. is measured. For 2 deg. the difference would amount to nearly 1/10th of an inch. Bessel confined his measures to distances considerably less than 1 deg.

[4] In criticizing Bessel's choice of methods, and considering the loss of time involved in each, it must be remembered that Fraunhofer provided no means of reading the screws or even the heads from the eye-end. Bessel's practice was to unclamp in declination, lower and read off the head, and then restore the telescope to its former declination reading, the clockwork meanwhile following the stars in right ascension. The setting of both lenses symmetrically would, under such circumstances, be very tedious.

[5] This most important improvement would permit any two stars under measurement each to be viewed in the optical axis of each segment. The optical centres of the segments would also remain at the same distance from the eye-piece at all angles of separation. Thus, in measuring the largest as well as the smallest angles, the images of both stars would be equally symmetrical and equally well in focus. Modern heliometers made with cylindrical slides measure angles over 2 deg., the images remaining as sharp and perfect as when the smallest angles are measured.

[6] Bessel found, in course of time, that the original corrections for the errors of his screw were no longer applicable. He considered that the changes were due to wear, which would be much lessened if the screws were protected from dust.

[7] The tube, being of wood, was probably liable to warp and twist in a very uncertain way.

[8] We have been unable to find any published drawing showing how the segments are fitted in their cells.

[9] We have been unable to ascertain the reasons which led Bessel to choose _ivory_ planes for the end-bearings of his screws. He actually introduced them in the Konigsberg heliometer in 1840, and they were renewed in 1848 and 1850.

[10] A screen of wire gauze, placed in front of the segment through which the fainter star is viewed, was employed by Bessel to equalize the brilliancy of the images under observation. An arrangement, afterwards described, has been fitted in modern heliometers for placing the screen in front of either segment by a handle at the eye-end.

[11] This heliometer resembles Bessel's, except that its foot is a solid block of granite instead of the ill-conceived wooden structure that supported his instrument. The object-glass is of 7.4 in. aperture and 123 in. focus.

[12] _Description de l'observatoire central de Pulkowa_, p. 208.

[13] Steinheil applied such motion to a double-image micrometer made for Struve. This instrument suggested to Struve the above-mentioned idea of employing a similar motion for the heliometer.

[14] Manuel Johnson, M.A., Radcliffe observer, _Astronomical Observations made at the Radcliffe Observatory, Oxford, in the Year 1850_, Introduction, p. iii.

[15] The illumination of these scales is interesting as being the first application of electricity to the illumination of astronomical instruments. Thin platinum wire was rendered incandescent by a voltaic current; a small incandescent electric lamp would now be found more satisfactory.

[16] For a detailed description of this instrument see _Dunecht Publications_, vol. ii.

[17] _Mem. Royal Astronomical Society_, xlvi., 1-172.

[18] The primary object was to have the object-glass mounted in steel cells, which more nearly correspond in expansion with glass. It became then desirable to make the head of steel for sake of uniformity of material, and the advantages of steel in lightness and rigidity for the tube then became evident.

[19] For description of the earliest form see _Cambridge Phil. Trans._ vol. ii., and _Greenwich Observations_ (1840).

[20] Dawes (_Monthly Notices_, January 1858, and _Mem. R.A.S._ vol. xxxv. p. 150) suggested and used a valuable improvement for producing round images, instead of the elongated images which are otherwise inevitable when the rays pass through a divided lens of which the optical centres are not in coincidence, viz. "the introduction of a diaphragm having two circular apertures touching each other in a point coinciding with the line of collimation of the telescope, and the diameter of each aperture _exactly equal_ to the semidiameter of the cone of rays at the distance of the diaphragm from the local point of the object-glass." Practically the difficulty of making these diaphragms for the different powers of the _exact_ required equality is insuperable; but, if the observer is content to lose a certain amount of light, we see no reason why they may not readily be made slightly less. Dawes found the best method for the purpose in question was to limit the aperture of the object-glass by a diaphragm having a double circular aperture, placing the line joining the centres of the circles approximately in the position angle under measurement. Dawes successfully employed the double circular aperture also with Amici's micrometer. The present writer has successfully used a similar plan in measuring position angles of a Centauri with the heliometer, viz. by placing circular diaphragms on the two segments of the object-glass.

[21] Dollond provides for changing the power by sliding the lens d nearer to or farther from a.

HELIOPOLIS, one of the most ancient cities of Egypt, met with in the Bible under its native name On. It stood 5 m. E. of the Nile at the apex of the Delta. It was the principal seat of sun-worship, and in historic times its importance was entirely religious. There appear to have been two forms of the sun-god at Heliopolis in the New Kingdom--namely, Ra-Harakht, or Re'-Harmakhis, falcon-headed, and Etom, human-headed; the former was the sun in his mid-day strength, the latter the evening sun. A sacred bull was worshipped here under the name Mnevis (Eg. _Mreu_), and was especially connected with Etom. The sun-god Re' (see EGYPT: _Religion_) was especially the royal god, the ancestor of all the Pharaohs, who therefore held the temple of Heliopolis in great honour. Each dynasty might give the first place to the god of its residence--Ptah of Memphis, Ammon of Thebes, Neith of Sais, Bubastis of Bubastis, but all alike honoured Re'. His temple became in a special degree a depository for royal records, and Herodotus states that the priests of Heliopolis were the best informed in matters of history of all the Egyptians. The schools of philosophy and astronomy are said to have been frequented by Plato and other Greek philosophers; Strabo, however, found them deserted, and the town itself almost uninhabited, although priests were still there, and cicerones for the curious traveller. The Ptolemies probably took little interest in their "father" Re', and Alexandria had eclipsed the learning of Heliopolis; thus with the withdrawal of royal favour Heliopolis quickly dwindled, and the students of native lore deserted it for other temples supported by a wealthy population of pious citizens. In Roman times obelisks were taken from its temples to adorn the northern cities of the Delta, and even across the Mediterranean to Rome. Finally the growth of Fostat and Cairo, only 6 m. to the S.W., caused the ruins to be ransacked for building materials. The site was known to the Arabs as _'Ayin esh shems_, "the fountain of the sun," more recently as Tel Hisn. It has now been brought for the most part under cultivation, but the ancient city walls of crude brick are to be seen in the fields on all sides, and the position of the great temple is marked by an obelisk still standing (the earliest known, being one of a pair set up by Senwosri I., the second king of the Twelfth Dynasty) and a few granite blocks bearing the name of Rameses II.

See Strabo xvii. cap. 1. 27-28; Baedeker's _Egypt_. (F. Ll. G.)

HELIOSTAT (from Gr. [Greek: helios], the sun, [Greek: statos], fixed, set up), an instrument which will reflect the rays of the sun in a fixed direction notwithstanding the motion of the sun. The optical apparatus generally consists of a mirror mounted on an axis parallel to the axis of the earth, and rotated with the same angular velocity as the sun. This construction assumes that the sun describes daily a small circle about the pole of the celestial sphere, and ignores any diurnal variation in the declination. This variation is, however, so small that it can be neglected for most purposes.

Many forms of heliostats have been devised, the earliest having been described by Wilhelm Jacob s' Gravesande in the 3rd edition of his _Physices elementa_ (1742). One of the simplest consists of a plane mirror rigidly connected with a revolving axis so that the angle between the normal to the mirror and the axis of the instrument equals half the sun's polar distance, the mirror being adjusted so that the normal has the same right ascension as the sun. It is easily seen that if the mirror be rotated at the same angular velocity as the sun the right ascensions will remain equal throughout the day, and therefore this device reflects the rays in the direction of the earth's axis; a second fixed mirror reflects them in any other fixed direction. Foucault's heliostat reflects the rays horizontally in any required direction. The principle of the apparatus may be explained by reference to fig. 1. The axis of rotation AB bears a rigidly attached rod DBC inclined to it at an angle equal to the sun's polar distance. By adjusting the right ascension of the plane ABC and rotating the axis with the angular velocity of the sun, it follows that BC will be the direction of the solar rays throughout the day. X is the mirror rotating about the point E, and placed so that (if EB is the horizontal direction in which the rays are to be reflected) (1) the normal CE to the mirror is jointed to BC at C and is equal in length to BE, (2) the rod DBC passes through a slot in a rod ED fixed to, and in the plane of, the mirror. Since CE equals BE these directions are equally inclined to, and coplanar with, the normal to the mirror. Hence light incident along the direction BC will be reflected along CE. Silbermann's heliostat reflects the rays in any direction. The principle may be explained by means of fig. 2. AB is the axis of rotation, BC an adjustable rod as in Foucault's construction, and BD is another rod which can be set to the direction in which the rays are to be reflected. The rods BC and DB carry two small rods EF, GF jointed at F; at this joint there is a pin which slides in a slot on the rod BH, which is normal to the mirror X. The rods EF, GF are such that BEFG is a rhombus. It is easy to show that rays falling on the mirror in the direction BC will be reflected along BD. One construction of the instrument, described in Jamin's _Cours de physique_, is shown in fig. 3. The mirror mm is attached to the framework _pafe_, the members of which are parallel to the incident and reflected rays SO, OR, and the diagonal pf is perpendicular to the mirror. The framework is attached to two independent circular arcs Cs and rr' having their centres at O and provided with clamps D and A on the axis F of the instrument. The arc Cs is graduated, and is set so that the angle COD equals the complement of the sun's declination. This can be effected (after setting the axis) by rotating Cs until a needle indicates true time on the hour dial B. The arc rr' is set so as to reflect the rays in the required direction. The axis F of the instrument is set at an angle equal to the latitude of the place of observation and in the meridian by means of the screw K, and rotated by clockwork contained in the barrel H. The setting in the meridian is effected by turning the instrument after setting for latitude until a pin-hole aperture s and a small screen P, placed so that Ps is parallel to CO, are in a line with the sun.

Many other forms of heliostats have been designed, the chief difference consisting in the mechanical devices for maintaining the constant direction of the reflecting ray. One of the most important applications of the heliostat is as an adjunct to the newer forms of horizontal telescopes (q.v.) and in conjunction with spectroscopic telescopes in observations of eclipses.

HELIOTROPE, or TURNSOLE, _Heliotropium_ (Gr. [Greek: heliotropion], i.e. a plant which follows the sun with its flowers or leaves, or, according to Theophrastus (_Hist, plant_, vii. 15), which flowers at the summer solstice), a genus of usually more or less hairy herbs or undershrubs of the tribe _Heliotropieae_ of the natural order Boraginaceae, having alternate, rarely almost opposite leaves; small white, lilac or blue flowers, in terminal or lateral one-sided simple or once or twice forked spikes, with a calyx of five deeply divided segments, a salver-shaped, hypogynous, 5-lobed corolla, and entire 4-celled ovary; fruit 2- to 4-sulcate or lobed, at length separable into four 1-seeded nutlets or into two hard 2-celled carpels. The genus contains 220 species indigenous in the temperate and warmer parts of both hemispheres. A few species are natives of Europe, as _H. europaeum_, which is also a naturalized species in the southern parts of North America.

The common heliotrope of English hothouses, _H. peruvianum_, popularly known as "cherry-pie," is on account of the delicious odour of its flowers a great favourite with florists. It was introduced into Europe by the younger Jussieu, who sent seed of it from Peru to the royal garden at Paris. About the year 1757 it was grown in England by Philip Miller from seed obtained from St Germains. _H. corymbosum_ (also a native of Peru), which was grown in Hammersmith nurseries as early as 1812, has larger but less fragant flowers than _H. peruvianum_. The species commonly grown in Russian gardens is _H. suaveolens_, which has white, highly fragrant flowers.

Heliotropes may be propagated either from seed, or, as commonly, by means of cuttings of young growths taken an inch or two in length. Cuttings when sufficiently ripened, are struck in spring or during the summer months; when rooted they should be potted singly into small pots, using as a compost fibry loam, sandy peat and well-decomposed stable manure from an old hotbed. The plants soon require to be shifted into a pot a size larger. To secure early-flowering plants, cuttings should be struck in August, potted off before winter sets in, and kept in a warm greenhouse. In the spring larger pots should be given, and the plants shortened back to make them bushy. They require frequent shiftings during the summer, to induce them to bloom freely.

The heliotrope makes an elegant standard. The plants must in this case be allowed to send up a central shoot, and all the side growths must be pinched off until the necessary height is reached, when the shoot must be stopped and lateral growths will be produced to form the head. During winter they should be kept somewhat dry, and in spring the ball of soil should be reduced and the plants repotted, the shoots being slightly pruned, so as to maintain a symmetrical head. When they are planted out against the walls and pillars of the greenhouse or conservatory an abundance of highly perfumed blossoms will be supplied all the year round. From the end of May till October heliotropes are excellent for massing in beds in the open air by themselves or with other plants. Many florists' varieties of the common heliotrope are known in cultivation.

Pliny (_Nat. hist._ xxii. 29) distinguishes two kinds of "heliotropium," the _tricoccum_, and a somewhat taller plant, the _helioscopium_; the former, it has been supposed, is _Croton tinctorium_, and the latter the [Greek: heliotropion mikron] of Dioscorides or _Heliotropium europaeum_. The helioscopium, according to Pliny, was variously employed in medicine; thus the juice of the leaves with salt served for the removal of warts, whence the term _herba verrucaria_ applied to the plant. What, from the perfume of its flowers, is sometimes called winter heliotrope, is the fragrant butterbur, or sweet-scented coltsfoot, _Petasites_ (_Tussilago_) _fragrans_, a perennial Composite plant.

HELIOTROPE, in mineralogy, is the mineral commonly called "bloodstone" (q.v.), and sometimes termed girasol--a name applied also to fire-opal. The name, like those of many ancient names of minerals, seems to have had a fanciful origin. According to Pliny the stone was so called because when thrown into the water it turned the sun's light falling upon it into a reflection like that of blood.

HELIOZOA, in zoology, a group of the Sarcodina (q.v.) so named by E. Haeckel, 1866. They are characterized by the radiate pseudopods, finely tapering at the apex, springing abruptly from the superficial protoplasm, containing a denser, rather permanent axial rod (figs. 1 (1), 2 (2)); protoplasm without a clear ectoplasm or pellicle, often frothy with large vacuoles, like the alveoli of Radiolaria; nucleus 1 or numerous; skeleton absent, gelatinous or of separate siliceous fibres, plates or spicules, rarely complete and latticed; reproduction by simple fission or by brood-formation, often syngamous; form usually nearly spherical, rarely changing slowly. This group was formerly included with the Rhizopoda; but was separated from it by Haeckel on account of the character of its pseudopods, and its general adaptation to a semipelagic existence correlated with the frothy cytoplasm (fig. 1 (1)). _Actinophrys sol_ and _Actinosphaerium eichhornii_ (fig. 2), known as sun animalcules to the older microscopists, float freely in stagnant or slow-flowing waters, and _Myriophrys_ is able by an investment of long flagelliform cilia to swim freely. The majority, however, lurk among confervae or the light debris of the bottom ooze; and come under the head of "sapropelic" rather than pelagic organisms. The body is usually of constant spherical form in relation to the floating habit. _Nuclearia_, however, shows amoeboid changes of general outline. The pseudopods are retractile, the axial filament being absorbed as the filament grows shorter and thicker and disappearing when the pseudopod merges into the ectoplasm, to be reformed at the same time with the pseudopod. There is often a distinction, clear, but never sharp, between the richly vacuolate, almost frothy ectoplasm and the denser endoplasm. One or more contractile vacuoles may protrude from the ectoplasm. The endoplasm contains the nucleus or nuclei. The nucleus when single may be central or excentric: in the latter case, the endoplasm contains a clear central sphere ("centrosome") on which abut the axial filaments of the pseudopods. The ectoplasm contains, in some species, constantly (_Raphidiophrys viridis_) or occasionally (_Actinosphaerium_), green cells belonging to the genera _Zoochlorella_ and _Sphaerocystis_, both probably--the latter certainly--vegetative stages of a Chlamydomonad (FLAGELLATA, q.v.) and of symbiotic significance.

The Heliozoa can move by rolling over on their extended pseudopods; _Acanthocystis ludibunda_ traversing a path of as much as twenty times its diameter in a minute, according to Penard. Several species (e.g. _Raphidiophrys elegans_) remain associated by the union of their pseudopods, whether into social aggregates (due to approximation) or "colonies" due to lack of separation after fission, is not accurately known. The multinuclear species _Actinosphaerium eichhornii_ (fig. 2), normally apocytial (i.e. the nuclei divide repeatedly without division of the cytoplasm), may increase in size by the fusion ("plastogamic") of small individuals. If a large specimen be cut up or fragment itself under irritation, the small ones so produced soon approach one another and fuse completely.

_Reproduction._--Binary fission has been repeatedly observed; in some cases one or both of the daughter cells may swim for a time as a biflagellate zoospore (fig. 1 (6, 7)). The process may take place when the cell is naked or after preliminary encystment. Budding has been well studied in _Acanthocystis_; the cell nucleus divides repeatedly and most of the daughter nuclei pass to the periphery, aggregate part of the cytoplasm, and with it are constricted off as independent cells; one nucleus remains central and the process may be repeated. The detached bud may assume the typical character after a short amoeboid (lobose) stage, sometimes preceded by rest, or it may develop 2 flagella and swim off (fig. 1 (6)).

Brood formation is only known here in relation to a syngamic process; this is a sharp contrast to Proteomyxa (q.v.) where brood formation is the commonest mode of reproduction, and plasmodium-formation, rare indeed, is the nearest approach to syngamy observed. Indeed, if we knew the life-history of all the species this difference in the life cycle would be a convenient critical character.

Equal conjugation was demonstrated fully by F. Schaudinn in _Actinophrys_; two individuals approach and enter into close contact, and are surrounded by a common cyst wall. The nucleus of either male divides; and one nucleus passes to the surface at either side, and is budded off with a small portion of the cytoplasm as an abortive cell; the two remaining nuclei which are "first cousins" in cellular relationship now fuse, as is the case with the cytoplasts. The resulting coupled cell or zygote divides into two, which again encyst.

_Actinosphaerium_ (fig. 2) shows a still more remarkable process, fully studied by R. Hertwig. The large multinucleate animal withdraws its pseudopods, its vacuoles disappear, it encysts and its nuclei diminish in number to about 1/20th partly by fusion, 2 and 2, probably by digestion of the majority. Within the primary cyst the body is now resolved into nuclear cells, which again surround themselves with secondary cysts. The cell in each secondary cyst divides (by karyokinesis), and these sister cells, or rather their offspring, pair in much the same way as the individual cells of _Actinophrys_--the chief difference is that after the first division and budding off of a rudimentary cell, a second division of the same character takes place, with the formation of a second rudimentary cell, which is the niece of the first, absolutely in the same way as the 1st and 2nd polar bodies are formed in the maturation of the ovum in Metazoa. The actual pairing cells are thus second cousins, great-granddaughters of the original cell of the secondary cysts. Complete fusion now takes place to form the coupled cell, which is now contracted and forms a gelatinous wall within the siliceous secondary cyst wall (fig. 2 (14)), During a resting stage nuclear divisions occur and finally a brood of young 1-nuclear _Actinosphaerium_ leave the cyst.

_Classification._

Aphrothoraca. Body naked. Actinophrys Ehrb. (fig. 1 (1)) (nucleate), Actinosphaerium Stein plurinucleate (fig. 2 (1)), Camptonema (plurinucleate) Schaud., Dimorpha Gruber (sometimes 2 flagellate).

I. Chlamydophora. Investment gelatinous. Astrodiscus.

II. Chalarothoraca. Body protected by an investment of spicules or fibre scattered or approximated, never fused into a continuous skeleton.

S 1. Spicules netted or free in the protoplasm. Heterophrys Arch. (fig. 1 (3)), Raphidiophrys Arch. (fig. 1 (4)), Pinacodocystis, Hertw. and Less.

S 2. Spicules approximated radially. Pinaciophora Greeff, Pompholyxophrys Arch., Lithocolla F. E. Schultze, Elaeorhanis Greeff (in the two foregoing genera the spicules represented by sand granules), Acanthocystis Carter (fig. 1 (5)), Pinacocystis (?) Hertw. and Less, Myriophrys Penard. (Astrodisculus).

III. Desmothoraca. S 1 attached by a stalk. Clathrulina Cienk. (fig. 1 (2, 7)), Hedriocystis, Hertw. and Less.

S 2. Free Elaster, Grimin, Choanocystis.

_Literature._--The most important English original papers on this group are those by W. Archer, "On some Freshwater Rhizopoda, new, or little known," _Quarterly Journal of Microscopic Science_, N.S. ix.-xi. (1869-1871), and "Resume of Recent Contributions to the Knowledge of Freshwater Rhizopods," _ibid._ xvi., xvii. (1876-1877). See also R. Hertwig and Lesser, "Uber Rhizopoda und denselben nahestehenden Organismen," in _Archiv fur mikroscopische Anatomie_, x. (1874), p. 35; R. Schaudinn, "Heliozoa" in _Tierreich_ (1896); E. Penard, _Les Heliozoaires d'eau douce_ (1904); the two last named contain full bibliographies. (M. Ha.)

HELIUM (from Gr. [Greek: helios], the sun), a gaseous chemical element, the modern discovery of which followed closely on that of argon (q.v.). The Investigations of Lord Rayleigh and Sir William Ramsay had shown that indifference to chemical reagents did not sufficiently characterize an unknown gas as nitrogen, and it became necessary to reinvestigate other cases of the occurrence of "nitrogen" in nature. H. Miers drew Ramsay's attention to the work of W. F. Hillebrand, who had noticed, in examining the mineral uraninite, that an inert gas was evolved when the mineral was decomposed with acid. Ramsay, repeating these experiments, found that the inert gas emitted refused to oxidize when sparked with oxygen, and on examining it spectroscopically he saw that the spectrum was not that of argon, but was characterized by a bright yellow line near to, but not identical with, the D line of sodium. This was afterwards identified with the D3 line of the solar chromosphere, observed in 1868 by Sir J. Norman Lockyer, and ascribed by him to a hypothetical element _helium_. This name was adopted for the new gas.

Helium is relatively abundant in many minerals, all of which are radioactive, and contain uranium or thorium as important constituents. (For the significance of this fact see RADIOACTIVITY.) The richest known source is thorianite, which consists mainly of thorium oxide, and contains 9.5 cc. of helium per gram. Monazite, a phosphate of thorium and other rare earths, contains on the average about 1 cc. per gram. Cleveite, samarskite and fergusonite contain a little more than monazite. The gas also occurs in minute quantities in the common minerals of the earth's crust. In this case too it is associated with radioactive matter, which is almost ubiquitous. In two cases, however, it has been found in the absence of appreciable quantities of uranium and thorium compounds, namely in beryl, and in sylvine (potassium chloride). Helium is contained almost universally in the gases which bubble up with the water of thermal springs. The proportion varies greatly. In the hot springs of Bath it amounts to about one-thousandth part of the gas evolved. Much larger percentages have been recorded in some French springs (_Compt. rend._, 1906, 143, p. 795, and 146, p. 435), and considerable quantities occur in some natural gas (_Journ. Amer. Chem. Soc._ 29, p. 1524). R. J. Strutt has suggested that helium in hot springs may be derived from the disintegration of common rocks at great depths.

Helium is present in the atmosphere, of which it constitutes four parts in a million. It is conspicuous by its absorption spectrum in many of the white stars. Certain stars and nebulae show a bright line helium spectrum.

Much the best practical source of helium is thorianite, a mineral imported from Ceylon for the manufacture of thoria. It dissolves readily in strong nitric acid, and the helium contained is thus liberated. The gas contains a certain amount of hydrogen and oxides of carbon, also traces of nitrogen. In order to get rid of hydrogen, some oxygen is added to the helium, and the mixture exploded by an electric spark. All remaining impurities, including the excess of oxygen, can then be taken out of the gas by Sir James Dewar's ingenious method of absorption with charcoal cooled in liquid air. Helium alone refuses to be absorbed, and it can be pumped off from the charcoal in a state of absolute purity. In the absence of liquid air the helium must be purified by the methods employed for argon (q.v.). If thorianite cannot be obtained, monazite, which is more abundant, may be utilized. A part of the helium contained in minerals can be extracted by heat or by grinding (J. A. Gray, _Proc. Roy. Soc._, 1909, 82A, p. 301).

_Properties._--All attempts to make helium enter into stable chemical union have hitherto proved unsuccessful. The gas is in all probability only mechanically retained in the minerals in which it is found. Jacquerod and Perrot have found that quartz-glass is freely permeable to helium below a red-heat (_Compt. rend._, 1904, 139, p. 789). The effect is even perceptible at a temperature as low as 220 deg. C. Hydrogen, and, in a much less degree, oxygen and nitrogen, will also permeate silica, but only at higher temperatures. They have made this observation the basis of a practical method of separating helium from the other inert gases. M. Travers has suggested that it may explain the liberation of helium from minerals by heat, the gas being enabled to permeate the siliceous materials in which it is enclosed. Thorianite, however, contains no silica, and until it is shown that metallic oxides behave in the same way this explanation must be accepted with reserve.

The density of helium has been determined by Ramsay and Travers as 1.98. Its ratio of specific heats has very nearly the ideal value 1.666, appropriate to a monatomic molecule. The accepted atomic weight is accordingly double the density, i.e. approximately four times that of hydrogen. The refractivity of helium is 0.1238 (air = 1). The solubility in water is the lowest known, being, at 18.2 deg., only .0073 vols. per unit volume of water. The viscosity is .96 (air = 1).

The spectrum of helium as observed in a discharge tube is distinguished by a moderate number of brilliant lines, distributed over the whole visual spectrum. The following are the approximate wave-lengths of the most brilliant lines:

Red 7066 Red 6678 Yellow 5876 Green 4922 Blue 4472 Violet 4026

When the discharge passes through helium at a pressure of several millimetres, the yellow line 5876 is prominent. At lower pressures the green line 4922 becomes more conspicuous. At atmospheric pressure the discharge is able to pass through a far greater distance in helium than in the common gases.

M. Travers, G. Senter and A. Jacquerod (_Phil. Trans._ A. 1903, 200, p. 105) carefully examined the behaviour of a constant volume gas thermometer filled with helium. For the pressure coefficient per degree, between 0 deg. and 100 deg. C., they give the value .00366255, when the initial pressure is 700 mm. This value is indistinguishable from that which they find for hydrogen. Thus at high temperatures a helium thermometer is of no special advantage. At low temperatures, on the other hand, they find, using an initial pressure of 1000 mm., that the temperatures on the helium scale are measurably higher than on the hydrogen scale, owing to the more perfectly gaseous condition of helium. This difference amounts to about 1/10 deg. at the temperature of liquid oxygen, and about 1/5 deg. at that of liquid hydrogen.

The liquefaction of helium was achieved by H. Kamerlingh Onnes at Leiden in 1908. According to him its boiling point is 4.3 deg. abs. (-268.7 deg. C.), the density of the liquid 0.154, the critical temperature 5 deg. abs., and the critical pressure 2.3 atmospheres (_Communications from the Physical Laboratory at Leiden_, No. 108; see also LIQUID GASES).

REFERENCES.--A bibliography and summary of the earlier work on helium will be found in a paper by Ramsay, _Ann. chim. phys._ (1898) [7], 13, p. 433. See also M. Travers, _The Study of Gases_ (1901). (R. J. S.)

HELIX (Gr. [Greek: helix], a spiral or twist), an architectural term for the spiral tendril which is carried up to support the angles of the abacus of the Corinthian capital; from the same stalk springs a second helix rising to the centre of the capital, its junction with one on the opposite side being sometimes marked by a flower. Sometimes the term "volute" is given to the angle helix, which is incorrect, as it is of a different design and rises from the same stalk as the central helices. Its origin is probably metallic, that is to say, it was copied from the conventional treatment in Corinthian bronze of the tendrils of a plant.

HELL (O. Eng. _hel_, a Teutonic word from a root meaning "to cover," cf. Ger. _Holle_, Dutch _hel_), the word used in English both of the place of departed spirits and of the place of torment of the wicked after death. It is used in the Old Testament to translate the Hebrew _Sheol_, and in the New Testament the Greek [Greek: hades], Hades, and [Greek: geenna], Hebrew _Gehenna_ (see ESCHATOLOGY).

HELLANICUS of Lesbos, Greek logographer, flourished during the latter half of the 5th century B.C. According to Suidas, he lived for some time at the court of one of the kings of Macedon, and died at Perperene, a town on the gulf of Adramyttium opposite Lesbos. Some thirty works are attributed to him--chronological, historical and episodical. Mention may be made of: _The Priestesses of Hera at Argos_, a chronological compilation, arranged according to the order of succession of these functionaries; the _Carneonikae_, a list of the victors in the Carnean games (the chief Spartan musical festival), including notices of literary events; an _Atthis_, giving the history of Attica from 683 to the end of the Peloponnesian War (404), which is referred to by Thucydides (i. 97), who says that he treated the events of the years 480-431 briefly and superficially, and with little regard to chronological sequence: _Phoronis_, chiefly genealogical, with short notices of events from the times of Phoroneus the Argive "first man" to the return of the Heraclidae; _Troica_ and _Persica_, histories of Troy and Persia.

Hellanicus marks a real step in the development of historiography. He transcended the narrow local limits of the older logographers, and was not content to repeat the traditions that had gained general acceptation through the poets. He tried to give the traditions as they were locally current, and availed himself of the few national or priestly registers that presented something like contemporary registration. He endeavoured to lay the foundations of a scientific chronology, based primarily on the list of the Argive priestesses of Hera, and secondarily on genealogies, lists of magistrates (e.g. the archons at Athens), and Oriental dates, in place of the old reckoning by generations. But his materials were insufficient and he often had recourse to the older methods. On account of his deviations from common tradition, Hellanicus is often called an untrustworthy writer by the ancients themselves, and it is a curious fact that he appears to have made no systematic use of the many inscriptions which were ready to hand. Dionysius of Halicarnassus censures him for arranging his history, not according to the natural connexion of events, but according to the locality or the nation he was describing; and undoubtedly he never, like his contemporary Herodotus, rose to the conception of a single current of events wider than the local distinction of race. His style, like that of the older logographers, was dry and bald.

Fragments in Muller, _Fragmenta historicorum Graecorum_, i. and iv.; see among older works L. Preller, _De Hellanico Lesbio historico_ (1840); Mure, _History of Greek Literature_, iv.; late criticism in H. Kullmer, "Hellanikos" in _Jahrbucher fur klass. Philologie_ (Supplementband, xxvii. 455 sqq.) (1902), which contains new edition and arrangement of fragments; C. F. Lehmann-Haupt, "Hellanikos, Herodot, Thukydides," in _Klio_ vi. 127 sqq. (1906); J. B. Bury, _Ancient Greek Historians_ (1909), pp. 27 sqq.

HELLEBORE (Gr. [Greek: helleboros]: mod. Gr. also [Greek: skaphe]: Ger. _Nieswurz_, _Christwurz_; Fr. _hellebore_, and in the district of Avranche, _herbe enragee_), a genus (_Helleborus_) of plants of the natural order Ranunculaceae, natives of Europe and western Asia. They are coarse perennial herbs with palmately or pedately lobed leaves. The flowers have five persistent petaloid sepals, within the circle of which are placed the minute honey-containing tubular petals of the form of a horn with an irregular opening. The stamens are very numerous, and are spirally arranged; and the carpels are variable in number, sessile or stipitate and slightly united at the base and dehisce by ventral suture.

_Helleborus niger_, black hellebore, or, as from blooming in mid-winter it is termed the Christmas rose (Ger. _Schwarze Nieswurz_; Fr., _rose de Noel_ or _rose d'hiver_), is found in southern and central Europe, and with other species was cultivated in the time of Gerard (see _Herball_, p. 977, ed. Johnson, 1633) in English gardens. Its knotty root-stock is blackish-brown externally, and, as with other species, gives origin to numerous straight roots. The leaves spring from the top of the root-stock, and are smooth, distinctly pedate, dark-green above, and lighter below, with 7 to 9 segments and long petioles. The scapes, which end the branches of the rhizome, have a loose entire bract at the base, and terminate in a single flower, with two bracts, from the axis of one of which a second flower may be developed. The flowers have 5 white or pale-rose, eventually greenish sepals, 15 to 18 lines in breadth; 8 to 13 tubular green petals containing honey; and 5 to 10 free carpels. There are several forms, the best being _maximus_. The Christmas rose is extensively grown in many market gardens to provide white flowers forced in gentle heat about Christmas time for decorations, emblems, &c.

_H. orientalis_, the Lenten rose, has given rise to several fine hybrids with _H. niger_, some of the best forms being clear in colour and distinctly spotted. _H. foetidus_, stinking hellebore, is a native of England, where like _H. viridis_, it is confined chiefly to limestone districts; it is common in France and the south of Europe. Its leaves have 7- to 11-toothed divisions, and the flowers are in panicles, numerous, cup-shaped and drooping, with many bracts, and green sepals tinged with purple, alternating with the five petals.

_H. viridis_, or green hellebore proper, is probably indigenous in some of the southern and eastern counties of England, and occurs also in central and southern Europe. It has bright yellowish-green flowers, 2 to 4 on a stem, with large leaf-like bracts. O. Brunfels and H. Bock (16th century) regarded the plant as the black hellebore of the Greeks.

_H. lividus_, holly-leaved hellebore, found in the Balearic Islands, and in Corsica and Sardinia, is remarkable for the handsomeness of its foliage. White hellebore is _Veratrum album_ (see VERATRUM), a liliaceous plant.

Hellebores may be grown in any ordinary light garden mould, but thrive best in a soil of about equal parts of turfy loam and well-rotted manure, with half a part each of fibrous peat and coarse sand, and in moist but thoroughly-drained situations, more especially where, as at the margins of shrubberies, the plants can receive partial shade in summer. For propagation cuttings of the rhizome may be taken in August, and placed in pans of light soil, with a bottom heat of 60 deg. to 70 deg. Fahr.; hellebores can also be grown from seed, which must be sown as soon as ripe, since it quickly loses its vitality. The seedlings usually blossom in their third year. The exclusion of frost favours the production of flowers; but the plants, if forced, must be gradually inured to a warm atmosphere, and a free supply of air must be afforded, without which they are apt to become much affected by greenfly. For potting, _H. niger_ and its varieties, and _H. orientalis_, _atrorubens_ and _olympicus_ have been found well suited. After lifting, preferably in September, the plants should receive plenty of light, with abundance of water, and once a week liquid manure, not over-strong. The flowers are improved in delicacy of hue, and are brought well up among the leaves, by preventing access of light except to the upper part of the plants. Of the numerous species of hellebore now grown, the deep-purple-flowered _H. colchicus_ is one of the handsomest; by crossing with _H. guttatus_ and other species several valuable garden forms have been produced, having variously coloured spreading or bell-shaped flowers, spotted with crimson, red or purple.

The rhizome of _H. niger_ occurs in commerce in irregular and nodular pieces, from about 1 to 3 in. in length, white and of a horny texture within. Cut transversely it presents internally a circle of 8 to 12 cuneiform ligneous bundles, surrounded by a thick bark. It emits a faint odour when cut or broken, and has a bitter and slightly acrid taste. The drug is sometimes adulterated with the rhizome of baneberry, _Actaea spicata_, which, however, may be recognized by the distinctly cruciate appearance of the central portion of the attached roots when cut across, and by its decoction giving the chemical reactions for tannin.[1] The rhizome is darker in colour in proportion to its degree of dryness, age and richness in oil. A specimen dried by Schroff lost in eleven days 65% of water.

_H. niger_, _orientalis_, _viridis_, _foetidus_, and several other species of hellebore contain the glucosides _helleborin_, C36H42O6, and _helleborein_, C23H20O15, the former yielding glucose and _helleboresin_, C30H38O4, and the latter glucose and a violet-coloured substance _helleboretin_, C14H20O3. Helleborin is most abundant in _H. viridis_. A third and volatile principle is probably present in _H. foetidus_. Both helleborin and helleborein act poisonously on animals, but their decomposition-products helleboresin and helleboretin seem to be devoid of any injurious qualities. Helleborin produces excitement and restlessness, followed by paralysis of the lower extremities or whole body, quickened respiration, swelling and injection of the mucous membranes, dilatation of the pupil, and, as with helleborein, salivation, vomiting and diarrhoea. Helleborein exercises on the heart an action similar to that of digitalis, but more powerful, accompanied by at first quickened and then slow and laboured respiration; it irritates the conjunctiva, and acts as a sternutatory, but less violently than veratrine. Pliny states that horses, oxen and swine are killed by eating "black hellebore"; and Christison (_On Poisons_, p. 876, 11th ed., 1845) writes: "I have known severe griping produced by merely tasting the fresh root in January." Poisonous doses of hellebore occasion in man singing in the ears, vertigo, stupor, thirst, with a feeling of suffocation, swelling of the tongue and fauces, emesis and catharsis, slowing of the pulse, and finally collapse and death from cardiac paralysis. Inspection after death reveals much inflammation of the stomach and intestines, more especially the rectum. The drug has been observed to exercise a cumulative action. Its extract was an ingredient in Bacher's pills, an empirical remedy once in great repute in France. In British medicine the rhizome was formerly official. _H. foetidus_ was in past times much extolled as an anthelmintic, and is recommended by Bisset (_Med. Ess._, pp. 169 and 195, 1766) as the best vermifuge for children; J. Cook, however, remarks of it (_Oxford Mag._, March 1769, p. 99): "Where it killed not the patient, it would certainly kill the worms; but the worst of it is, it will sometimes kill both." This plant, of old termed by farriers ox-heel, setter-wort and setter-grass, as well as _H. viridis_ (Fr. _Herbe a seton_), is employed in veterinary surgery, to which also the use of _H. niger_ is now chiefly confined in Britain.

In the early days of medicine two kinds of hellebore were recognized, the white or _Veratrum album_ (see VERATRUM), and the black, including the various species of _Helleborus_. The former, according to Codronchius (_Comm.... de elleb._, 1610), Castellus (_De helleb. epist._, 1622), and others, is the drug usually signified in the writings of Hippocrates. Among the hellebores indigenous to Greece and Asia Minor, _H. orientalis_, the rhizome of which differs from that of _H. niger_ and of _H. viridis_ in the bark being readily separable from the woody axis, is the species found by Schroff to answer best to the descriptions given by the ancients of black hellebore, the [Greek: helleboros melas] of Dioscorides. The rhizome of this plant, if identical, as would appear, with that obtained by Tournefort at Prusa in Asia Minor (_Rel. d'un voy. du Levant_, ii. 189, 1718), must be a remedy of no small toxic properties. According to an early tradition, black hellebore administered by the soothsayer and physician Melampus (whence its name _Melampodium_), was the means of curing the madness of the daughters of Proetus, king of Argos. The drug was used by the ancients in paralysis, gout and other diseases, more particularly in insanity, a fact frequently alluded to by classical writers, e.g. Horace (_Sat._ ii. 3. 80-83, _Ep. ad Pis._ 300). Various superstitions were in olden times connected with the cutting of black hellebore. The best is said by Pliny (_Nat. hist._ xxv. 21) to grow on Mt Helicon. Of the three Anticyras that in Phocis was the most famed for its hellebore, which, being there used combined with "sesamoides," was, according to Pliny, taken with more safety than elsewhere.

The British Pharmaceutical Conference has recommended the preparation which it terms _the tinctura veratri viridis_, as the best form in which to administer this drug. It may be given in doses of 5-15 minims. The tincture is prepared from the dried rhizome and rootlets of green hellebore, containing the alkaloids jervine, veratrine and veratroidine. It is recommended as a cardiac and nervous sedative in cerebral haemorrhage and puerperal eclampsia. Black hellebore is a purgative and uterine stimulant.

FOOTNOTE:

[1] For the microscopical characters and for figures of transverse sections of the rhizome, see Lanessan, _Hist. des drogues_, i. 6 (1878).

HELLENISM (from Gr. [Greek: hellenizein], to imitate the Greeks, who were known as [Greek: Hellenes], after [Greek: Hellen], the son of Deucalion). The term "Hellenism" is ambiguous. It may be used to denote ancient Greek culture in all its phases, and even those elements in modern civilization which are Greek in origin or in spirit; but, while Matthew Arnold made the term popular in the latter connexion as the antithesis of "Hebraism," the German historian J. G. Droysen introduced the fashion (1836) of using it to describe particularly the latter phases of Greek culture from the conquests of Alexander to the end of the ancient world, when those over whom this culture extended were largely not Greek in blood, i.e. _Hellenes_, but peoples who had adopted the Greek speech and way of life, _Hellenistai_. Greek culture had, however, both in "Hellenic" and "Hellenistic" times, a common essence, just as light is light whether in the original luminous body or in a reflection, and to describe this by the term Hellenism seems most natural. But whilst using the term in the larger sense, this article, in deference to the associations which have come to be specially connected with it, will devote its principal attention to Hellenism as it appeared in the world after the Macedonian conquests. But it will be first necessary to indicate briefly what Hellenism in itself implied.

No verbal formula can really enclose the life of a people or an age, but we can best understand the significance of the old Greek cities and the life they developed, when, looking at the history of mankind as a whole, we see the part played by reason, active and critical, in breaking down the barriers by which custom hinders movement, in guiding movement to definite ends, in dissipating groundless beliefs and leading onwards to fresh scientific conquests--when we see this and then take note that among the ancient Greeks such an activity of reason began in an entirely novel degree and that its activity in Europe ever since is due to their impulsion. When Hellenism came to stand in the world for something concrete and organic, it was, of course, no mere abstract principle, but embodied in a language, a literature, an artistic tradition. In the earliest existing monument of the Hellenic genius, the Homeric poems, one may already observe that regulative sense of form and proportion, which shaped the later achievements of the race in the intellectual and artistic spheres. It was not till the great colonizing epoch of the 8th and 7th centuries B.C., when the name "Hellene" came into use as the antithesis of "barbarian," that the Greek race came to be conscious of itself as a peculiar people; it was yet some three centuries more before Hellenism stood fully declared in art and literature, in politics and in thought. There was now a new thing in the world, and to see how the world was affected by it is our immediate concern.

I. THE EXPANSION OF HELLENISM BEFORE ALEXANDER.--In the 5th century B.C. Greek cities dotted the coasts of the Mediterranean and the Black Sea from Spain to Egypt and the Caucasus, and already Greek culture was beginning to pass beyond the limits of the Greek race. Already in the 7th century B.C., when Hellenism was still in a rudimentary stage, the citizens of the Greek city-states had been known to the courts of Babylon and Egypt as admirable soldiers, combining hardihood with discipline, and Greek mercenaries came to be in request throughout the Nearer East. But as Hellenism developed, its social and intellectual life began to exercise a power of attraction. The proud old civilizations of the Euphrates and the Nile might ignore it, but the ruder barbarian peoples in East and West, on whose coasts the Greek colonies had been planted, came in various degrees under its spell. In some cases an outlying colony would coalesce with a native population, and a fusion of Hellenism with barbarian customs take place, as at Emporium in Spain (Strabo iii. p. 160) and at Locri in S. Italy (Polyb. xii. 5. 10). Perinthus included a Thracian phyle. The stories of Anacharsis and Scylas (Herod, iv. 76-80) show how the leading men of the tribes in contact with the Greek colonies in the Black Sea might be fascinated by the appeal which the exotic culture made to mind and to eye.

The great developments of the century and a half before Alexander set the Greek people in a very different light before the world. In the sphere of material power the repulse of Xerxes and the extension of Athenian or Spartan supremacy in the eastern Mediterranean were large facts patent to the most obtuse. The kings of the East leant more than ever upon Greek mercenaries, whose superiority to barbarian levies was sensibly brought home to them by the expedition of Cyrus. But the developments within the Hellenic sphere itself were also of great consequence for its expansion outwards. The political disunion of the Greeks was to some extent neutralized by the rise of Athens to a leading position in art, in literature and in philosophy. In Athens the Hellenic genius was focussed, its tendencies drawn together and combined; nor was it a circumstance of small moment that the Attic dialect attained, for prose, a classical authority; for if Hellenism was to be propagated in the world at large, it was obviously convenient that it should have some one definite form of speech to be its medium.

1. _The Persians._--The ruling race of the East, the Persian, was but little open to the influences of the new culture. The military qualities of the Greeks were appreciated, and so, too, was Greek science, where it touched the immediately useful; a Greek captain was entrusted by Darius with the exploration of the Indus; a Greek architect bridged the Bosporus for him; Greek physicians (e.g. Democedes, Ctesias) were retained for enormous fees at the Persian court. The brisk diplomatic intercourse between the Great King and the Greek states in the 4th century may have produced effects that were not merely political. We certainly find among those members of the Persian aristocracy, who came by residence in Asia Minor into closer contact with the Greeks, some traces of interest in the more ideal side of Hellenism. A man like the younger Cyrus invited Greek captains to his friendship for something more than their utility in war, and procured Greek hetaerae for something more than sensual pleasure. There is the Mithradates who presented the Academy with a statue of Plato by Silanion, not improbably identical (though the supposition implies a correction in the text of Diogenes Laertius) with that Mithradates who, together with his father Ariobarzanes, received the citizenship of Athens (Dem. xxiii. 141, 202). Exactly how far Greek influence can be traced in the remains of Persian art, such as the royal palaces of Persepolis and Susa may be doubtful (see Gayet, _L'Art persan_; R. Phene Spiers, _Architecture East and West_, p. 245 f.), but it is certain that the engraved gems for which there was a demand in the Persian empire were largely the work of Greek artists (Furtwangler, _Antike Gemmen_, iii. p. 116 f.).

2. _The Phoenicians._--As early as the first half of the 4th century we find communities of Phoenician traders established in the Peiraeus (_C.I.A._ ii. 86). In Cyprus, on the frontier between the Greek and Semitic worlds, a struggle for ascendancy went on. The Phoenician element seems to have been dominant in the island when Evagoras made himself king of Salamis in 412, and restored Hellenism with a strong hand. The words of Isocrates (even allowing for their rhetorical colour) give us a vivid insight into what such a process meant. "Before Evagoras established his rule, they were so hostile and exclusive, that those of their rulers were actually held to be the best who were the fiercest adversaries of the Greeks; but now such a change has taken place, that it is a matter of emulation who shall show himself the most ardent phil-hellen, that for the mothers of their children most of them choose wives from amongst us, and that they take pride in having Greek things about rather than native, in following the Greek fashion of life, whilst our masters of the fine arts and other branches of culture now resort to them in greater numbers than were once to be found in those quarters they specially frequented" (Isoc. 199 = _Evag._ SS 49, 50). Even into the original seats of the Phoenicians Hellenism began to intrude. Evagoras at one time (about 386) made himself master of Tyre (Isoc. _Evag._ S 62; Diod. xv. 2, 4). His grandson Evagoras II. is found as governor of Sidon for the Persian king 349-346. (Babelon, _Perses Achemenides_, p. cxxii.; cf. Diod. xvi. 46, 3).

Abdashtart, king of Sidon (374-362 B.C.), called Straton by the Greeks, had already entered into close relations with the Greek states, and imitated the Hellenic princes of Cyprus (_Athen._ xii. 531; _C.I.A._ ii. 86; _Corp. inscr. Semit._ i. 114). The Phoenician colonists in Sardinia purchased or imitated the work of Greek artists (Furtwangler, _Antike Gemmen_, iii. 109).

3. _The Carians and Lycians._--The seats of the Greeks in the East touched peoples more or less nearly related to the Hellenic stock, with native traditions not so far remote from those of the Greeks in a more primitive age, the Carians and the Lycians. It came about in the last century preceding Alexander that the first of these peoples was organized as a strong state under native princes, the line founded by Hecatomnus of Mylasa. Hecatomnus made himself master of Caria in the first decade of the 4th century, but it was under his son Mausolus, who succeeded him in 377-376 that the house rose to its zenith. These Carian princes ruled as satraps for the Great King, but they modelled themselves upon the pattern of the Greek tyrant. The capital of Mausolus was a Greek city, Halicarnassus, and all that we can still trace of his great works of construction and adornment shows conformity to the pure Hellenic type. His famous sepulchre, the Mausoleum (the remains of it are now in the British Museum), was a monument upon which the most eminent Greek sculptors of the time worked in rivalry (Plin. _N.H._ xxxvi. 5, S 30; Vitruv. vii. 13). His court gave a welcome to the vagrant Greek philosopher (Diog. Laert. viii. 8, S 87). Even the Carian town of Mylasa now shows the forms of a Greek city and records its public decrees in Greek (_C.I.G._ 2691 c, d, e = Michel 471). In Lycia, which in spite of "the son of Harpagus" and King Pericles, had never been brought under one man's rule, the Greek influence is more limited. Here, for the most part in the inscriptions, the native language maintains itself against Greek. The proper names are (if not native) mainly Persian. But the Greek language makes an occasional appearance; Greek names are borne by others beside Pericles. The coins are Greek in type. And above all the monumental remains of Lycia show strong Greek influence, especially the well-known "Nereid Monument" in the British Museum, whose date is held to go back to the 5th century (Gardner, _Handbook of Gk. Sculp._ p. 344).

4. _South Russia._--Hellenic influences continued to penetrate the Scythian peoples from the Greek colonies of the Black Sea, at any rate in the matter of artistic fabrication. Our evidence is the actual objects recovered from the soil. (See SCYTHIA.)

5. _Egypt._--From the time of Psammetichus (d. 610 B.C.) Greek mercenaries had been used to prop Pharaoh's throne. At the same time Greek merchants had begun to find their way up the Nile and even to the Oases. A Greek city Naucratis (q.v.) was allowed to arise at the Bolbitinic mouth of the Nile. But the racial repugnance to the Greek, which forbade an Egyptian even to eat an animal which had been carved with a Greek's knife (Hdt. ii. 41), probably kept the soul of the people more shut against Hellenic influences than was that of the other races of the East.

6. _Macedonia._--In Macedonia the native chiefs had been attracted by the rich Hellenic life at any rate from the beginning of the 5th century, when Alexander I., surnamed "Phil-hellen," persuaded the judges at Olympia that the Temenid house was of good Argive descent (Hdt. v. 22). And, although their enemies might stigmatize them as barbarians, the Macedonian kings maintained that they were not Macedonians, but Greeks (cf. [Greek: aner Hellen Makedonon hyparchos], Hdt. v. 20). It was not probably till the reorganization of the kingdom by Archelaus (413-399) that Greek culture found any abundant entrance into Macedonia. Now all that was most brilliant in Greek literature and Greek art was concentrated in the court of Aegae; the palace was decorated by Zeuxis; Euripides spent there the end of his days. From that time, no doubt, a certain degree of literary culture was general among the Macedonian nobility; their names in the days of Philip are largely Greek; the Macedonian service was full of men from the Greek cities within Philip's dominions. The values recognized at the court would naturally be recognized in noble families generally, and Philip chose Aristotle to be the educator of his son. How far the country generally may be regarded as Hellenized is a problem which involves the vexed question what right the Macedonian people itself has to be classed among the Hellenes, and Macedonian to be considered a dialect of Greek.[1] As the literary and official language, Greek alone would seem to have had any status.

7. _In the West: the Native Races of Sicily._--Italy and the south of Gaul had not remained unaffected by the neighbourhood of the Greek colonies. Under the rule of the elder and younger Dionysius in the 4th century, the hellenization of the Sicels in the interior of Sicily seems to have become complete (Freeman, _History of Sicily_, ii. 387, 388, 422-424; Beloch, _Griech. Gesch._ iii. [i.] 261).

The alphabets used by the various Italian races from the 5th century were directly or indirectly learnt from the Greeks. The peoples of the south (Lucanians, Bruttians, Mamertines) show a Greek principle of nomenclature (Mommsen, _Unterital. Dialekt_, p. 240 f.). The Pythagorean philosophy, whose seat was in southern Italy, won adherents among the native chiefs (Cic. _De senec._ 12, cf. Dio Chrys. _Orat. Cor._ 37, S 24). From the Greeks of southern Gaul Hellenic influences penetrated the Celtic races so far that imitations of Greek coins were struck even on the coasts of the Atlantic.

II. AFTER ALEXANDER THE GREAT.--When we review generally the extent to which Hellenism had penetrated the outer world in the middle of the 4th century B.C., it must be admitted that it had not seriously affected any but the more primitive races which dwelt upon the borders of the Hellenic lands, and here it would seem, with the doubtful exception of the Macedonians, to have been an affair rather of the courts than of the life of the people. On the other hand it must be taken into account that Hellenism had as yet only been a very short while in the world. What would have happened had it continued to depend upon its spiritual force only for propagation we cannot say. Everything was changed when by the conquests of Alexander (334-323) it suddenly rose to material supremacy in all the East as far as India, and when cities of Greek speech and constitution were planted by the might of kings at all the cardinal points of intercourse within those lands. The values honoured by the rulers of the world must naturally impress themselves upon the subject multitudes. The Macedonian chiefs found their pride in being champions of Hellenism. Of Alexander there is no need to speak. The courts of his successors in Asia Minor, Syria and Egypt were Greek in language and atmosphere. All kings liked to win the good word of the Greeks by munificence bestowed upon Greek cities and Greek institutions. All of them in some degree patronized Greek art and letters, and some sought fame for themselves as authors. Even the barbarian courts, their neighbours or vassals, were swayed by the dominant fashion to imitation. But by the courts alone Hellenism could never have been propagated far. Greek culture had been the product of the city-state, and Hellenism could not be dissevered from the city. It was upon the system of Greek and Macedonian cities, planted by Alexander and his successors, that their work rested, and though their dynasties crumbled, their work remained. Rome, when it stepped into their place, did no more than safeguard its continuance; in the East Rome acted as a Hellenistic power, and if, when the legions had thundered past, the brooding East "plunged in thought again," that thought was largely directed by the Greek schoolmaster who followed in the legions' train. From our present point of view we may therefore regard this work of Hellenism as one continuous process, initiated by the Macedonians and carried on under Roman protection, and ask in the first place what the institution of a Greek city implied.

_The Character of the New Greek Cities._--The citizen bodies at the outset were really of Greek or Macedonian blood--soldiers who had served in the royal armies, or men attracted from the older Greek cities to the new lands thrown open to commerce. To fix their European soldiery upon the new soil was an obvious necessity for the Macedonian chiefs who had set up kingdoms among the barbarians, and the lots of the veterans (except in Egypt) were naturally attached to various urban centres. The cities, of course, drew in numbers beside of the people of the land; Alexander is specially said to have incorporated large bodies of natives in some of the new cities of the Eastern provinces (Arr. iv. 4, 1; Diod. xvii. 83, 2; Curtius ix. 10, 7). It may generally be taken for granted that the lower strata of the city-populations was mainly native; to be included in the city population was not, however, to be included in the citizen body, and it remains a question how far the latter admitted members of other than European origin (Beloch iii. [i.] 414). The statements, for instance, of Josephus that the Jews were given full citizen rights in the new foundations are probably false (Willrich, _Juden und Griechen vor der makkabaischen Erhebung_, 1895, p. 19 f.). The social organization of the citizen-body conformed to the regular Hellenic type with a division into _phylae_ and, in Egypt, at any rate, into _demi_ (Liban. Or. xix. 62; Satyrus, frag. 21 = _F.H.G._ iii. 164; Sir W. M. Ramsay, _Cities and Bishoprics_, i. 60; Kenyon, _Archiv f. Papyr._ ii. 74; Jonguet, _Bull. corr. hell._ xxi., 1897, 184 f.; Liebenam, _Stadteverwaltung_, 220 f.). The cities appear equally Hellenic in their political organs and functions with _boule_ and _demos_ and popularly elected magistrates. Life was filled with the universal Hellenic interests, which centred in the gymnasium and the religious festivals, these last including, of course, not only athletic contests but performances of the classical dramas or later imitations of them. The wandering sophist and rhetorician would find a hearing no less than the musical artist. The language of the upper classes was Greek; and the material background of building and decoration, of dress and furniture, was of Greek design. A greater regularity in the street-plans seems to have distinguished the new cities from the older slowly grown cities of the Greek lands, just as it distinguishes the cities of the New World to-day from those of Europe. Alexandria and Antioch were both traversed from end to end by one long straight street, crossed by shorter ones at right angles; Nicaea was a square from the centre of which all the four gates could be seen at the ends of the intersecting thoroughfares (Strabo xii. 565); similar characteristics are noted in the rebuilt Smyrna (ib. xiv. 646).

Sometimes the Greek city was not an absolutely new foundation, but an old Oriental city, re-colonized and transformed. And in such cases the old name was often replaced by a Greek one. Thus Celaenae in Phrygia became Apamea; Haleb (Aleppo) in Syria became Beroea; Nisibis in Mesopotamia, Antioch; Rhagae (Rai) in Media, Europus. In some cases the old name was left unchallenged, e.g. Thyatira, Damascus and Samaria. Even where there was no new foundation the older cities of Phoenicia and Syria became transformed from the overwhelming prestige of Hellenic culture. In Tyre and Sidon, no less than in Antioch or Alexandria, Greek literature and philosophy were seriously cultivated, as we may see by the great names which they contributed. The process by which Hellenism thus leavened an older city we may trace with peculiar vividness in the case of Jerusalem; we see there the younger generation captivated by its ideals, the appearance of gymnasium and theatre, the eager adoption of Greek political forms (1 Macc. i. 13 f.; 2 Macc. 4., 10 f.).

A. _Characteristics of Hellenism after Alexander._--To the number of Greek city-states existing before Alexander were now therefore added those which extended Hellas as far as India. With the enormous extension of Greek territory a great shifting took place in the old centres of gravity. What changes in the character of Greek culture did the new conditions of the world bring about?

Government.

Hellenism had been the product of the free life of the Greek city-state, and after Chaeronea the great days of the city-state were past. Not that all liberty was everywhere extinguished. Under Alexander himself the Greek states were restive, and Aetolia unsubdued; and, with the break-up of the empire at Alexander's death, there was once more scope for the action of the individual cities among the rival great powers. In the history of the next two or three centuries the cities are by no means ciphers. Rhodes takes a great part in _Weltpolitik_, as a sovereign ally of one or other of the royal courts. In Greece itself the overlordship to which the Macedonian king aspires is imperfect in extent and only maintained to that extent by continual wars. The Greek states on their side show that they are capable even of progressive political development, the needs of the time being met by the federal system, by larger unions of equal members than the leading cities of the past would have tolerated, with their extreme unwillingness to forego the least shred of sovereign independence. The Achaean and Aetolian Leagues are independent powers, which the Macedonian can indeed check by garrisons in Corinth, Chalcis and elsewhere, but which keep a field clear for Hellenic freedom within their borders. Sparta also is a power which can cross swords with the Macedonian king, and Cleomenes III. aspires to unite the Peloponnesus under his headship. As to the cities outside Greece, within or around the royal realms, Seleucid, Ptolemaic or Attalid, their degree of freedom probably differed widely according to circumstances. At one end of the scale, cities of old renown, e.g. Lampsacus or Smyrna, could still make good their independence against Antiochus III. at the beginning of the 2nd century B.C. At the other end of the scale the cities which were royal capitals, e.g. Alexandria, Antioch and Pergamum, were normally controlled altogether by royal nominees. At Pergamum indeed and (at any rate after Antiochus IV.) at Antioch, forms of self-government subsisted upon which, of course, the court had its hand, whilst at Alexandria even such forms were wanting. Between the two extremes there was variation not only between city and city, but, no doubt, in one and the same city at different times. In Syria the independent action of the cities greatly increased during the last weakness of the Seleucid monarchy. With the extension of the single strong rule of Rome over this Hellenistic world, the conditions were changed. Just as the Macedonian conquest, whilst increasing the domain of Greek culture, had straitened Greek liberty, so Rome, whilst bringing Hellenism finally into secure possession of the nearer East, extinguished Greek freedom altogether. Even now the old forms were long religiously respected. Formally, the most illustrious Greek states, Athens, for instance, or Marseilles, or Rhodes, were not subjects of Rome, but free allies. Even in the case of _civitates stipendiariae_ (tribute-paying states), municipal autonomy, subject indeed to interference on the part of the Roman governor, was allowed to go on. _Boule_ and _demos_ long continued to function. The old catchword, "autonomy of the Hellens," was still heard and indeed was solemnly proclaimed by Nero at the Isthmian games of A.D. 67. But during the first centuries of the Christian era, this municipal autonomy, by a process which can only be imperfectly traced in detail, decayed. The _demos_ first sank into political annihilation and the council, no longer popularly elected but an aristocratic order, concentrated the whole administration in its hands. By the end of the 2nd century A.D., claims made by the imperial government upon the municipal senate are more and more changing membership of the order from an honour into an intolerable burden, and financial disorganization is calling on imperial officials in one place after another to undertake the business of government. After Diocletian and under the Eastern Empire the Greek world is organized on the principles of a vast bureaucracy.

Social changes.

With this long process of political decline from Alexander to Diocletian correspond the inner changes in the temper of the Hellenic and Hellenistic peoples. There were, of course, marked differences between one region and another. But certain general characteristics distinguished at once Greek society after the Macedonian conquests from the society of the earlier age. When the vast field of the East was opened to Hellenic enterprise and the bullion of its treasuries flung abroad, fortunes were made on a scale before unparalleled. A new standard of sumptuousness and splendour was set up in the richest stratum of society. This material elaboration of life was furthered by the existence of Hellenistic courts, where the great ministers amassed fabulous riches (e.g. Dionysius, the state secretary of Antiochus IV., Polyb. xxxi. 3, 16; Hermias, the chief minister of Seleucus III., and Antiochus III., Polyb. v. 50. 2; cf. Plutarch, _Agis_ 9), and of huge cities like Alexandria, Antioch and the enlarged Ephesus. It is significant that whereas the earlier Greeks had used precious stones only as a medium for the engraver's art, unengraven gems, valuable for their mere material, now came to be used in profusion for adornment. Already before Alexander pan-hellenic feeling had in various ways overridden the internal divisions of the Greek race, but now, with the vast mingling of Greeks of all sorts in the newly-conquered lands, a generalized Greek culture in which the old local characteristics were merged, came to overspread the world. The gradual supersession of the old dialects by the Koine the common speech of the Greeks, a modification of the Attic idiom coloured by Ionic, was one obvious sign of the new order of things (see GREEK LANGUAGE).

Art and literature.

In its artistic, its literary, its spiritual products the age after Alexander gave evidence of the change. In no department did activity immediately stop; but the old freshness and creative exuberance was gone. Artistic pleasure, grown less delicate, required the stimulus of a more sensational effect or a more striking realism, as we may see by the Pergamene and Rhodian schools of sculpture, by the bas-reliefs with the _genre_ subjects drawn from the life of the countryside, or, in literature by the sort of historical writing which became popular with Cleitarchus and Duris, by the studied emotional or rhetorical point of Callimachus, and by the portrayal of country life in Theocritus. At the same time, artists and men of letters were now addressing themselves in most cases, not to their fellow-citizens in a free city, but to kings and courtiers, or the educated class generally of the Greek world. In those departments of intellectual activity which demand no high ideal faculty, in the study of the world of fact, the centuries immediately following Alexander witnessed notable advance. Scientific research might prosper, just as poetry withered, under the patronage of kings, and such research had now a vast amount of new material at its disposal and could profit by the old Babylonian and Egyptian traditions. The medical schools, especially that of Alexandria, really enlarged knowledge of the animal frame. Knowledge of the earth gained immensely by the Macedonian conquests. The literary schools of Alexandria and Pergamum built up grammatical science, and brought literary and artistic criticism to a fine point. If indeed the earlier ages had been those of creative and spontaneous life, the Hellenistic age was that of conscious criticism and book-learning. The classical products were registered, studied, assorted and commented upon. Men travelled and read more. Books were in demand and were multiplied. Libraries became a feature of the age, the kings leading the way as collectors, of books, especially the rival dynasties of Egypt and Pergamum. The library attached to the Museum at Alexandria is said to have contained at the time of its destruction in 47 B.C. as many as 700,000 rolls (Aul. Gell. vi. 17. 3). Even smaller cities, like Aphrodisias in Caria, had public libraries for the instruction of their youth (Le Bas, III. No. 1618).

With the general decay of ancient civilization under the Roman empire, even scientific research ceased, and though there were literary revivals, like that connected with the new Atticism under the Antonine emperors, these were mainly imitative and artificial, and even learning became at last under the Byzantine emperors a jejune and formal tradition (see GREEK LITERATURE).

Religion and philosophy.

The diffusion of the Greek race far from the former centres of its life, the mingling of citizens of many cities, the close contact between Greek and barbarian in the conquered lands--all this had made the old sanctions of civic religion and civic morality of less account than ever. New guides of life were needed. The Stoic philosophy, with its cosmopolitan note, its fixed dogmas and plain ethical precepts, came into the world at the time of the Macedonian conquests to meet the needs of the new age. Its ideas became popular among ordinary men as the older philosophies had never been. The Stoic or Cynic preacher, attacking the ways of society, in pungent, often coarse, phrase, became a familiar figure of the Greek market-place (P. Wendland, _Beitrage zur Gesch. d. griech. Philosophie_, 1895).

Although the cults of the old Greek deities in the new cities, with their splendid apparatus of festivals and sacrifice might still hold the multitude, men turned ever in large numbers to alien religions, felt as more potent because strange, and the various gods of Egypt and the East began to find larger entrance in the Greek world. Even in the old Greek religion before Alexander there had been large elements of foreign origin, and that the Greeks should now do honour to the gods of the lands into which they came, as we find the Cilician and Syrian Greeks doing to Baal-tars and Baal-marcod and the Egyptian Greeks to the gods of Egypt, was only in accordance with the primitive way of thinking. But it was a sign of the times when Serapis and Isis, Osiris and Anubis began to take place among the popular deities in the old Greek lands. The origin of the cult of Serapis, which Ptolemy I. found, or established, in Egypt is disputed; the familiar type of the god is the invention of a Greek artist, but the name and religion came from somewhere in the East (see discussion under SERAPIS). Before the end of the 2nd century B.C. there were temples of Serapis in Athens, Rhodes, Delos and Orchomenos in Boeotia. Under the Roman empire the cult of Isis, now furnished with an official priesthood and elaborate ritual, became really popular in the Hellenistic world. King Asoka in the 3rd century B.C. sent Buddhist missionaries from India to the Mediterranean lands; their preaching has, it is true, left little or no trace in our Western records. But other religions of Oriental origin penetrated far, the worship of the Phrygian Great Mother, and in the 2nd century A.D. the religion of the Mithras (Lafaye, _Culte des divinites alexandrines_, 1884; Roscher, articles "Anubis," "Isis," &c.; F. Cumont, _Mysteres de Mithra_, Eng. trans., 1903; _Les Religions orientales dans le paganisme romain_, 1906).

The Jews, too, by the time of Christ were finding in many quarters an open door. Besides those who were ready to go the whole length and accept circumcision, numbers adopted particular Jewish practices, observing the Sabbath, for instance, or turned from polytheism to the doctrine of the One God. The synagogues in the Gentile cities had generally attached to them, in more or less close connexion a multitude of those "who feared God" and frequented the services (Schurer, _Gesch. d. jud. Volks_, iii. 102-135).

Christianity.

Among the religions which penetrated the Hellenistic world from an Eastern source, one ultimately overpowered all the rest and made that world its own. The inter-action of Christianity and Hellenism opens large fields of inquiry. The teaching of Christ Himself contained, as it is given to us, no Hellenic element; so far as He built with older material, that material was exclusively the sacred tradition of Israel. So soon, however, as the Gospel was carried in Greek to Greeks, Hellenic elements began to enter into it, in the writings, for instance, of St Paul, the appeal to what "nature" teaches would be generally admitted to be the adoption of a Greek mode of thought. It was, of course, impossible that speaking in Greek and living among Greeks, Christians should not to some extent use current conceptions for the expression of their faith. There was, at the same time, in the early Church a powerful current of feeling hostile to Greek culture, to the wisdom of the world. What the attitude of the New People should be to it, whether it was all bad, or whether there were good things in it which Christians should appropriate, was a vital question that always confronted them. The great Christian School of Alexandria represented by Clement and Origen effected a durable alliance between Greek education and Christian doctrine. In proportion as the Christian Church had to go deeper into metaphysics in the formulation of its belief as to God, as to Christ, as to the soul, the Greek philosophical terminology, which was the only vehicle then available for precise thought, had to become more and more an essential part of Christianity. At the same time Christian ethics incorporated much of the current popular philosophy, especially large Stoical elements. In this way the Church itself, as we shall see, became a propagator of Hellenism (see Hatch, _Hibbert Lectures_, 1888; Wendland, "Christentum u. Hellenismus" in _Neue Jahrb. f. kl. Alt._ ix. 1902, p. 1 f.; and _Die hellenistisch-romische Kultur in ihren Beziehungen zu Judentum u. Christentum_, 1907).

B. _Effect upon non-Hellenic Peoples._--Hellenism secured by the Macedonian conquest _points d'appui_ from the Mediterranean to India, and brought the system of commerce and intercourse into Greek hands. What effect did it produce in these various countries? What effect again in the lands of the West which fell under the sway of Rome?

Greek cities.

Greek art.

(i.) _India._--In India (including the valleys of the Kabul and its northern tributaries, then inhabited by an Indian, not, as now, by an Iranian, population) Alexander planted a number of Greek towns. Alexandria "under the Caucasus" commanded the road from Bactria over the Hindu-Kush; it lay somewhere among the hills to the north of Kabul, perhaps at Opian near Charikar (MacCrindle, _Ancient India_, p. 87, note 4); that it is the city meant by "Alasadda the capital of the Yona (Greek) country" in the Buddhist Mahavanso, as is generally affirmed, seems doubtful (Tarn, loc. cit. below, p. 269, note 7). We hear of a Nicaea in the Kabul valley itself (near Jalalabad?), another Nicaea on the Hydaspes (Jhelum) where Alexander crossed it, with Bucephala (see BUCEPHALUS) opposite, a city (unnamed) on the Acesines (Chenab) (Arr.