Chapter 59

groups. The first of these comprises explosives in bulk, made-up cartridges for cannon, and filled quick- firing cartridges; Group II. contains small-arm cartridges, fuzes, primers, tubes, filled shells (fuzed or unfuzed), &c. Each group is subdivided, and arrangements are made for storing certain divisions of Group I. in a magazine in separate compartments. All the divisions of Group II. are, and the remaining divisions of Group I. (comprising wet gun-cotton, picric acid and Q.F. cartridges) may be, stored in ammunition stores.

These general conditions apply to the storage of ammunition in fortresses. Here the positions for the magazine and ammunition stores are so chosen as to afford the best means of protection from an enemy's fire. Huge earth parapets cover these buildings, which are further strengthened, where possible, by traverses protecting the entrances. For the purpose of filling, emptying and examining cannon cartridges and shell, a laboratory is generally provided at some distance from the magazine. The various stores for explosives are classified into those under magazine conditions (viz. magazines, laboratories and cartridge stores) and those with which these restrictions need not be observed (viz. ammunition and shell stores). The interior walls of a magazine are lined and the floors laid so that there may be no exposed iron or steel. At the entrance there is a lobby or barrier, inside which persons about to enter the magazine change their clothes for a special suit, and their boots for a pair made without nails. In an ammunition or shell store these precautions need not be taken except where the shell store and the adjacent cartridge store have a common entrance; persons entering may do so in their ordinary clothes. A large work may have a main magazine and several subsidiary magazines, from which the stock of cartridges is renewed in the cartridge stores attached to each group of guns or in the expense cartridge stores and cartridge recesses. The same applies to main ammunition stores which supply the shell stores, expense stores and recesses.

The supply of ammunition may be divided roughly into (a) that for guns forming the movable armament, (b) that for guns placed in permanent positions. The movable armament will consist of guns and howitzers of small and medium calibre, and it is necessary to arrange suitable expense cartridge stores and shell stores in close proximity to the available positions. They can generally be constructed to form part of the permanent work in the projected face of traverses or other strong formations, and should be arranged for a twenty-four hours' supply of ammunition. These stores are refilled from the main magazine every night under cover of darkness. Light railways join the various positions. The guns mounted in permanent emplacements are divided into groups of two or three guns each, and usually each group will require but one calibre of ammunition. A cartridge store, shell store and a general store, all well ventilated, are arranged for the especial service of such a group of guns. In the cartridge store the cylinders containing the cartridges are so placed and labelled that the required charge, whether reduced or full, can be immediately selected. In the shell store also for the same reason the common shell are separated from the armour-piercing or shrapnel. Each nature of projectile is painted in a distinctive manner to render identification easy. The fuzes, tubes, &c., are placed in the general store with the tools and accessories belonging to the guns. The gun group is distinguished by some letter and the guns of the group by numerals; thus, A/1 is No. I gun of group A. The magazine and shell stores are also indicated by the group letter, and so that mistakes, even by those unaccustomed to the fort, may be avoided, the passages are pointed out by finger posts and direction boards. For the immediate service of each gun a few cartridges and projectiles are stored in small receptacles--called cartridge and shell recesses respectively--built in the parapet as near the gun position as practicable. In some cases a limited number of projectiles may be placed close underneath the parapet if this is conveniently situated near the breech of the gun and not exposed to hostile fire.

In order to supply the ammunition sufficiently rapidly for the efficient service of modern guns, hydraulic, electric or hand-power hoists are employed to raise the cartridges and shell from the cartridge store and shell store to the gun floor, whence they are transferred to a derrick or loading tray attached to the mounting for loading the gun.

Projectiles for B.L. guns above 6-in. calibre are stored in shell stores ready filled and fuzed standing on their bases, except shrapnel and high-explosive shell, which are fuzed only when about to be used. Smaller sizes of shells are laid on their sides in layers, each layer pointing in the opposite direction to the one below to prevent injury to the driving bands. Cartridges are stored in brass corrugated cases or in zinc cylinders. The corrugated cases are stacked in layers in the magazine with the mouth of the case towards a passage between the stacks, so that it can be opened and the cartridges removed and transferred to a leather case when required for transport to the gun. Cylinders are stacked, when possible, vertically one above the other. The charges are sent to the gun in these cylinders, and provision is made for the rapid removal of the empty cylinders.

The number and nature of rounds allotted to any fortress depends on questions of policy and location, the degrees of resistance the nature of the works and personnel could reasonably be expected to give, and finally on the nature of the armament. That is to say, for guns of large calibre three hundred to four hundred rounds per gun might be sufficient, while for light Q.F. guns it might amount to one thousand or more rounds per gun. (A. G. H.)

Supply of ammunition in the field.

With every successive improvement in military arms there has necessarily been a corresponding modification in the method of supplying ammunition and in the quantity required to be supplied. When hand-to-hand weapons were the principal implements of battle, there was, of course, no such need, but even in the middle ages the archers and crossbowmen had to replenish the shafts and bolts expended in action, and during a siege stone bullets of great size, as well as heavy arrows, were freely used. The missiles of those days were, however, interchangeable, and at the battle of Towton (1461) the commander of the Yorkist archers, by inducing the enemy to waste his arrows, secured a double supply of ammunition for his own men. This interchangeability of war material was even possible for many centuries after the invention of firearms. At the battle of Liegnitz (1760) a general officer was specially commissioned by Frederick the Great to pack up and send away, for Prussian use, all the muskets and ammunition left on the field of battle by the defeated Austrians. Captured material is, of course, utilized whenever possible, at the present time, and in the Chino-Japanese War the Japanese went so far as to prepare beforehand spare parts for the Chinese guns they expected to capture (Wei-Hai-Wei, 1895), but it is rare to find a modern army trusting to captures for arms and ammunition; almost the only instance of the practice is that of the Chilean civil war of 1891, in which the army of one belligerent was almost totally dependent upon this means of replenishing stores of arms and cartridges. But what was possible with weapons of comparatively rough make is no longer to be thought of in the case of modern arms. The Lee-Metford bullet of .303 in. diameter can scarcely be used in a rifle of smaller calibre, and in general the minute accuracy of parts in modern weapons makes interchangeability almost impossible. Further, owing to the rapidity with which, in modern arms, ammunition is expended, and the fact that, as battles are fought at longer ranges than formerly, more shots have to be fired in order to inflict heavy losses, it is necessary that the reserves of ammunition should be as close as possible to the troops who have to use them. This was always the case even with the older firearms, as, owing to the great weight of the ammunition, the soldier could carry but few rounds on his person. Nevertheless it is only within the past seventy years that there has grown up the elaborate system of ammunition supply which now prevails in all regularly organized armies. That which is described in the present article is the British, as laid down in the official Combined Training (1905) and other manuals. The new system designed for stronger divisions, and others, vary only in details and nomenclature.

Infantry.--The infantry soldier generally carries, in pouches, bandoliers, &c., one hundred rounds of small-arms ammunition (S.A.A.), and it is usual to supplement this, when an action is imminent, from the regimental reserve (see below). It is to be noticed that every reduction in the calibre of the rifle means an increase in the number of rounds carried. One hundred rounds of the Martini-Henry ammunition weighed 10lb. 10 oz.; the same weight gives 155 with .303 ammunition (incl. charges), and if a .256 calibre is adopted the number of rounds will be still greater. It is, relatively, a matter of indifference that the reserves of ammunition include more rounds than formerly; it is of the highest importance that the soldier should, as far as possible, be independent of fresh supplies, because the bringing up of ammunition to troops closely engaged is laborious and costly in lives. The regimental reserves are carried in S.A.A. carts and on pack animals. Of the former each battalion has six, of the latter eight. The six carts are distributed, one as reserve to the machine gun, three as reserve to the battalion itself, and two as part of the brigade reserve, which consists therefore of eight carts. The brigade reserve communicates directly with the brigade ammunition columns of the artillery (see below). The eight pack animals follow the eight companies of their battalion. These, with two out of the three battalion carts, endeavour to keep close to the firing line, the remaining cart being with the reserve companies. Men also are employed as carriers, and this duty is so onerous that picked men only are detailed. Gallantry displayed in bringing up ammunition is considered indeed to justify special rewards. The amount of S.A.A. in regimental charge is 100 rounds in the possession of each soldier, 2000 to 2200 on each pack animal, and 16,000 to 17,600 in each of four carts, with, in addition, about 4000 rounds with the machine gun and 16,000 more in the fifth cart.

Artillery.--The many vehicles which accompany batteries (see ARTILLERY) carry a large quantity of ammunition, and with the contents of two wagons and the limber each gun may be considered as well supplied, more especially as fresh rounds can be brought up with relatively small risk, owing to the long range at which artillery fights and the use of cover. Each brigade of artillery has its own ammunition column, from which it draws its reserve in the first instance.

Ammunition Columns.--An ammunition column consists of military vehicles carrying gun and S.A. ammunition for the combatant unit to which the column belongs. Thus the ammunition columns of a division, forming part of the brigades of field artillery, carry reserve ammunition for the guns, the machine guns of the infantry and the rifles of all arms. Generally speaking, the ammunition column of each of the artillery brigades furnishes spare ammunition for its own batteries and for one of the brigades of infantry. All ammunition columns are officered and manned by the Royal Artillery. They are not reserved exclusively to their own brigades, divisions, &c., but may be called upon to furnish ammunition to any unit requiring it during an action. The officers and men of the R.A. employed with the ammunition column are, as a matter of course, immediately available to replace casualties in the batteries. Teams, wagons and materiel generally are also available for the same purpose. The horse artillery, howitzer and heavy brigades of artillery have each their own ammunition columns, organized in much the same way and performing similar duties. The ammunition column of the heavy brigade is divisible into three sections, so that the three batteries, if operating independently, have each a section at hand to replenish the ammunition expended. The horse artillery brigade ammunition columns carry, besides S.A.A. for all corps troops other than artillery, the reserve of pom-pom ammunition. In action these columns are on the battlefield itself. Some miles to the rear are the divisional and corps troops columns, which on the one hand replenish the empty wagons of the columns in front, and on the other draw fresh supplies from the depots on the line of communication. These also are in artillery charge; a divisional column is detailed to each division (i.e. to replenish each set of brigade ammunition columns), and the corps troops column supplies the columns attached to the heavy, howitzer and horse artillery brigades. The ammunition thus carried includes ordinarily seven or eight kinds at least. S.A.A., field, horse, howitzer and heavy gun shrapnel, howitzer and heavy gun lyddite shells, cartridges for the four different guns employed and pom-pom cartridges for the cavalry,--in all twelve distinct types of stores would be carried for a complete army corps. Consequently the rounds of each kind in charge of each ammunition column must vary in accordance with the work expected of the combatant unit to which it belongs. Thus pom-pom ammunition is out of place in the brigade ammunition columns of field artillery, and S.A.A. is relatively unnecessary in that attached to a heavy artillery brigade. Under these circumstances a column may be unable to meet the particular wants of troops engaged in the vicinity; for instance, a cavalry regiment would send in vain to a heavy artillery ammunition section for pom-pom cartridges. The point to be observed in this is that the fewer the natures of weapons used, the more certain is the ammunition supply. (C. F. A.)

The first projectiles fired from cannon were the darts and stone shot which had been in use with older weapons. These darts ("garros") had iron heads or were of iron wrapped with leather to fit the bore of small guns, and continued in use up to nearly the end of the 16th century. Spherical stone shot were chosen on account of cheapness; forged iron, bronze and lead balls were tried, but the expense prevented their general adoption. Further, as the heavy metal shot necessitated the use of a correspondingly large propelling charge, too great a demand was made on the strength of the feeble guns of the period. Stone shot being one-third the weight of those of iron the powder charge was reduced in proportion, and this also effected an economy. Both iron and stone shot were occasionally covered with lead, probably to preserve the interior of the bore of the gun. Cast iron, while known in the 14th century, was not sufficiently common to be much used for the manufacture of shot, although small ones were made about that time. They were used more frequently at the latter part of the following century. Towards the end of the 16th century nearly all shot were of iron, but stone shot were still used with guns called Petrieroes (hence the name) or Patararoes, for attacking weak targets like ships at short range.

Case shot are very nearly as ancient as spherical shot. They can be traced back to the early part of the 15th century, and they have practically retained their original form up to the present date. They are intended for use at close quarters when a volley of small shot is required. With field guns they are not of much use at ranges exceeding about four hundred yards; those for heavy guns are effective up to one thousand yards. In the earlier forms lead or iron shot were packed in wood casks or in canvas bags tied up with twine like the later quilted shot. In the present (fig. 2) type small shot are placed in a cylindrical case of sheet iron, with iron ends, one end being provided with handles. For small guns the bullets are made of lead and antimony--like shrapnel bullets--while for larger calibres they are of cast iron weighing from two ounces to three and a half pounds each.

Grape shot is now obsolete. It consisted generally of three tiers of cast-iron balls separated by iron plates and held in place by an iron bolt which passed through the centre of the plates.

There was also another type called quilted shot which consisted of a number of small shot in a canvas covering tied up by rope. Chain shot, in the days of sailing ships, was much in favour as a means of destroying rigging. Two spherical shot were fastened together by a short length of chain. On leaving the gun they began gyrating around each other and made a formidable missile.

Red-hot shot were invented in 1579 by Stephen Batory, king of Poland. They were used with great effect by the English during the siege of Gibraltar, especially on the 13th of September 1782, when the French floating batteries were destroyed, together with a large part of the Spanish fleet. Martin's shell was a modified form; here a cast-iron shell was filled with molten cast iron and immediately fired. On striking the side of a ship the shell broke up, freeing the still molten iron, which set fire to the vessel.

Rotation.--Projectiles intended for R.M.L. guns were at first fitted with a number of gun-metal studs arranged around them in a spiral manner corresponding to the twist of rifling. This was defective, as it allowed, as in the old smooth-bore guns, the powder gas to escape by the clearance (called "windage") between the projectile and the bore, with a consequent loss of efficiency; it also quickly eroded the bore of the larger guns. Later the rotation was effected by a cupped copper disc called a "gas check" attached to the base end of the projectile. The powder gas pressure expanded the rim of the gas check into the rifling grooves and prevented the escape of gas; it also firmly fixed the gas check to the projectile, thus causing it to rotate. A more regular and efficient action of the powder gas was thus ensured, with a corresponding greater range and an improvement in accuracy. With the earlier Armstrong (R.B.L.) guns the projectiles were coated with lead (the late Lord Armstrong's system), the lead being forced through the rifling grooves by the pressure of the exploded powder gas. The lead coating is, however, too soft with the higher velocities of modern B.L. guns. Mr Vavasseur, C.B., devised the plan of fitting by hydraulic pressure a copper "driving band" into a groove cut around the body of the projectile. This is now universal. It not only fulfils the purpose of rotating the projectile, but renders possible the use of large charges of slow- burning explosive. The copper band, on being forced through the gun, gives rise to considerable resistance, which allows the propelling charge to burn properly and thus to exert its enormous force on the projectile.

The laws which govern the designs of projectiles are not well defined. Certain formulae are used which give the thickness of the walls of the shell for a known chamber pressure in the gun, and for a particular stress on the material of the shell. The exact proportions of the shell depend, however, greatly on experimental knowledge.

Armour-piercing Shot and Shell.--On the introduction of iron ships it was found that the ordinary cast-iron projectile readily pierced the thin plating, and in order to protect the vital parts of the vessel wrought-iron armour of considerable thickness was placed on the sides. It then became necessary to produce a projectile which would pierce this armour. This was effected by Sir W. Palliser, who invented a method of hardening the head of the pointed cast-iron shot. By casting the projectile point downwards and forming the head in an iron mould, the hot metal was suddenly chilled and became intensely hard, while the remainder of the mould being formed of sand allowed the metal to cool slowly and the body of the shot to be made tough.

These shot proved very effective against wrought-iron armour, but were not serviceable against compound and steel armour. A new departure had, therefore, to be made, and forged steel shot with points hardened by water, &c., took the place of the Palliser shot. At first these forged steel shot were made of ordinary carbon steel, but as armour improved in quality the projectiles followed suit, and, for the attack of the latest type of cemented steel armour, the projectile is formed of steel--either forged or cast--containing both nickel and chromium. Tungsten steel has also been used with success.

Armour-piercing shot or shell are generally cast from a special mixture of chrome steel melted in pots; they are afterwards forged into shape. The shell is then thoroughly annealed, the core bored and the exterior turned up in the lathe. The shell is finished in a similar manner to others described below. The final or tempering treatment is very important, but details are kept strictly secret. It consists in hardening the head of the projectile and tempering it in a special manner, the rear portion being reduced in hardness so as to render it tough. The cavity of these projectiles is capable of receiving a small bursting charge of about 2% of the weight of the complete projectile, and when this is used the projectile is called an armour-piercing shell. The shell, whether fuzed or unfuzed, will burst on striking a medium thickness of armour. Armour-piercing shells, having a bursting charge of about 3% of the weight of the complete projectile, are now often fitted with a soft steel cap (fig. 3) for the perforation of hard steel armour. For the theory of the action of the cap see ARMOUR PLATES.

Even with these improvements the projectile cannot, with a reasonable velocity, be relied upon to pierce one calibre in thickness of modern cemented steel armour.

Explosive shells do not appear to have been in general use before the middle of the 16th century. About that time hollow balls of stone or cast iron were fired from mortars. The balls were nearly filled with gunpowder and the remaining space with a slow-burning composition. This plan was unsatisfactory, as the composition was not always ignited by the flash from the discharge of the gun, and moreover the amount of composition to burn a stipulated time could not easily be gauged. The shell was, therefore, fitted with a hollow forged iron or copper plug, filled with slow-burning powder. It was impossible to ignite with certainty this primitive fuze simply by firing the gun; the fuze was consequently first ignited and the gun fired immediately afterwards. This entailed the use of a mortar or a very short piece, so that the fuze could be easily reached from the muzzle without unduly endangering the gunner. Cast-iron spherical common shell (fig. 4) were in use up to 1871. For guns they were latterly fitted with a wooden disc called a sabot, attached by a copper rivet, intended to keep the fuze central when loading. They were also supposed to reduce the rebounding tendency of the shell as it travelled along the bore on discharge. Mortar shell (fig. 5) were not fitted with sabots.

Cast iron held its own as the most convenient material for projectiles up to recent years, steel supplanting it, first for projectiles intended for piercing armour, and afterwards for common shell for high-velocity guns where the shock of discharge has been found too severe for cast iron.

Common shell is essentially a material destructor. Filled with ordinary gunpowder, the larger natures are formidable projectiles for the attack of fortifications and the unarmoured portions of warships. On bursting they break up into somewhat large pieces, which carry destruction forward to some distance from the point of burst. For the attack of buildings common shell are superior to shrapnel and they are used to attack troops posted behind cover where it is impossible for shrapnel to reach them; their effect against troops is, however, generally insignificant. When filled with lyddite, melinite, &c., they are called high-explosive (H.E.) shell (see below). Common shell for modern high-velocity guns may be made of cast steel or forged steel; those made of cast iron are now generally made for practice, as they are found to break up on impact, even against earthworks, before the fuze has time to act; the bursting charge is, therefore, not ignited or only ignited after the shell has broken up, the effect of the bursting charge being lost in either case. So long as the shell is strong enough to resist the shocks of discharge and impact against earth or thin steel plates, it should be designed to contain as large a bursting charge as possible and to break up into a large number of medium-sized pieces. Their effect between decks is generally more far-reaching than lyddite shell, but the purely local effect is less. Light structures, which, at a short distance from the point of burst, successfully resist lyddite shell and confine the effect of the explosion, may be destroyed by the shower of heavy pieces produced by the burst of a large common shell.

To prevent the premature explosion of the shell, by the friction of the grains of powder on discharge, it is heated and coated internally with a thick lacquer, which on cooling presents a smooth surface. Besides this the bursting charge of all shell of 4-in. calibre and upwards (also with all other natures except shrapnel) is contained in a flannel or canvas bag. The bag is inserted through the fuze hole and the bursting charge of pebble and fine grain powder gradually poured in. The shell is tapped on the outside by a wood mallet to settle the powder down. When all the powder has been got in, the neck of the bag is tied and pushed through the fuze hole. A few small shalloon primer bags, filled with seven drams of fine grain powder, are then inserted to fill up the shell and carry the flash from the fuze through the burster bag.

In the United States specially long common shell called torpedo shell, about 4.7 calibres in length, are employed with the coast artillery 12-in. mortars. They were made of cast steel, but owing to a premature explosion in a mortar, supposed to be due to weakness of the shell, they are now made of forged steel. The weight of the usual projectile for this mortar is 850 lb. . The torpedo shell, however, weighs 1000 lb. and contains 137 lb. of high explosive; it is not intended for piercing armour but for producing a powerful explosion on the armoured deck of a warship. The compression, and consequent generation of heat on discharge of the charge in these long shell, render them liable to premature explosion if fired with high velocities. Some inventors have, therefore, sought to overcome this by dividing the shell transversely into compartments and so making each portion of the charge comparatively short.

Cast-steel common shell (fig. 6) are cast in sand moulds head downwards from steel of the required composition to give the proper tenacity. A large head, which is subsequently removed, is cast on the base to give solidity and soundness to the castings. The castings are annealed by placing them in a furnace or oven until red hot, then allowing them to cool gradually. The process of casting is very similar to that for the old cast-iron common shell, which, however, were cast base downwards. The steel castings after being annealed are dressed and carefully examined for defects. The exterior of the body is generally ground by an emery wheel or turned in a lathe; the groove for the driving band is also turned and the fuze hole fitted with a gun-metal bush. Forged-steel common shell are made from solid steel billets. These are heated to redness and shaped by a series of punches which force the heated metal through steel dies by hydraulic pressure. If the shell is intended for a nose fuze the base end is shaped by the press and the head subsequently formed by a properly shaped die, or, in the case of small shell, the head can, when red hot, be spun up in a lathe by a properly formed tool. For a base fuze shell the head is produced by the punches and dies, and the base is subsequently formed by pressing in the metal to the desired shape. The shell is then completed as described above.

High-explosive shell (fig. 7), as used in the English service, are simply forged-steel common shell filled with lyddite and having a special nose fuze and exploder. The base end of lyddite shell is made solid to prevent the possibility of the gas pressure in the gun producing a premature explosion. In filling the shell great precautions are necessary to prevent the melted lyddite (picric acid) from coming in contact with certain materials such as combinations of lead, soda, &c., which produce sensitive picrates. The shell are consequently painted externally with a special non-lead paint and lacquered inside with special lacquer. The picric acid is melted in an oven, the temperature being carefully limited. The melted material is poured into the shell by means of a bronze funnel, which also forms the space for the exploder of picric powder. On cooling, the material solidifies into a dense, hard mass (density 1.6), in which state it is called lyddite. The fuze on striking ignites the exploder and in turn the lyddite. When properly detonated a dense black smoke is produced and the projectile is broken up into small pieces, some of which are almost of the fineness of grains of sand. The radius of the explosion is about 25 yds., but the local effect is intense, and hence on light structures in a confined space the destruction is complete. The shell is only of use against thin plates; against modern armour it is ineffective. When detonation has not been complete, as sometimes happens with small shells, the smoke is yellowish and the pieces of the exploded shell are as large as when a powder burster is used.

The French high-explosive shell obus torpille or obus a melinite was adopted in 1886. The melinite was originally filled into the ordinary cast-iron common shell (obus ordinaire) with thick walls, but soon afterwards a forged-steel thin-walled shell (obus allonge) was introduced. To explode the shell a steel receptacle (called a gaine) is screwed into the nose of the shell. It is filled with explosive and fitted with a detonator which is exploded by a percussion fuze. Except for the means adopted to ensure detonation this shell is practically the same as the lyddite shell.

Picric acid in some form or other is used in nearly all countries for filling high-explosive shell. In some the explosive is melted and poured into cardboard cases instead of being poured directly into the shell. The cases are placed in the shell either by the head of the shell unscrewing from the body or by a removable base plug. The French melinite and the Italian pertite are believed to be forms of picric acid. Russia and the United States use compressed wet gun-cotton (density 1.2) as the charge for their high-explosive shell. The gun-cotton is packed in a thin zinc or copper case and is placed in the shell either by the head or base of the shell being removable. The gun-cotton is detonated by a powerful exploder, the form of which differs in each country. Ammonal is also used in high-explosive shell, but owing to its light density it is not in great favour. For field-gun and other small high-explosive shells, ordinary smokeless powder is often used.

Double shell is a term given to a common shell which was made abnormally long, so as to receive a large bursting charge. They were intended to be fired with a reduced charge at short range. They are now practically obsolete; their place with modern B.L. guns has been taken by high-explosive shell. Star shell are intended for illuminating the enemy's position. They are very similar to shrapnel shell, composition stars made up in cylindrical paper cases taking the place of the bullets. The shell on bursting, blows off the head and scatters the ignited stars. This shell is only supplied to mountain guns and howitzers, and takes the place of the older types of illuminating shell, viz. the ground light ball and the parachute light ball.

Hand grenades were used at the assault of entrenchments or in boat attacks. Although generally regarded as obsolete, they were much used by the Japanese at the siege of Port Arthur, 1904. In the British service they were small, thin, spherical common shell weighing 3 lb. for land service and 6 lb. for sea service, filled with powder. They were fitted with a small wood time fuze to burn 7.5 seconds. The grenade was held in the hand and the fuze lighted by a port-fire. It was then thrown some 20 to 30 yds. at the enemy's works or boats. Sometimes a number were fired from a mortar at an elevation of about 30 deg. so that none should strike the ground too near the mortar. New types of grenades filled with high explosives detonated by a percussion fuze have been produced of late years, and it is probable that they will be again introduced into most countries.

Shrapnel shell were invented by Lieutenant (afterwards Lieutenant- General) Henry Shrapnel, R.A. (1761-1842), in 1784. They were spherical common shell with lead bullets mixed with the bursting charge. Although far superior to common shell in man-killing effect, their action was not altogether satisfactory, as the shell on bursting projected the bullets in all directions, and there was a liability of premature explosion. In order to overcome these defects Colonel Boxer, R.A., separated the bullets from the bursting charge by a sheet-iron diaphragm--hence the name of "diaphragm shell" (fig. 8). The bullets were hardened by the addition of antimony, and, as the bursting charge was small, the shell was weakened by four grooves made inside the shell extending from the fuze hole to the opposite side.

With rifled guns the form of the shell altered, but its character remained. The body of the shell was still made of cast iron with a cavity at the base for the bursting charge; on this was placed a thick steel diaphragm with a hollow brass tube which communicated the flash from the nose fuze to the bursting charge. The body was filled with hard lead bullets, and a wood head covered with sheet iron or steel surmounted it and carried the fuze. By making the body of toughened steel (fig. 9) and by slightly reducing the diameter of the bullets, the number of bullets contained was much increased. In the older field shrapnel, bullets of 18 and 34 to the lb. were used; for later patterns see table in ORDNANCE: Field Equipments. Thus with the cast-iron body the percentage of useful weight, i.e. the proportion of the weight of the bullets to the total weight of the shell, was from 26 to 28%, while with modern steel shell it is from 47 to 53%. The limit of the forward effect of shrapnel at effective range is about 300 yds. and the extent of front covered 25 yds.

[Fig. 10 shows in plan the different effects of (a) shrapnel and of (b) high-explosive, burst in the air with a time fuze in the usual way. It will be seen that the shrapnel bullets sweep an area of about 250 yds. by 30 yds., half the bullets falling on the first 50 yds. of the beaten zone. With the high-explosive shell, however, the fragments strike the ground closer to the point of burst and beat a shallow, but broad, area of ground (about 7 yds. by 55 yds.). These areas show the calculated performance of the German field gun (96 N.A.), firing at a range of 3300 yds. In the case of the high- explosive shell, the concussion of the burst is highly dangerous, quite apart from the actual distribution of the fragments of the shell.]

The term "shooting shrapnel" is given to certain howitzer shrapnel, which are designed to contain a large bursting charge for the purpose of considerably augmenting the velocity of the bullets when the shell bursts.

High-explosive shell of a compound type have also lately appeared. Messrs Krupp have made a kind of ring shell with a steel body; a central tube conveys the flash from the fuze to a base magazine containing a smoke-producing charge, while surrounding the central tube is a bursting charge of ordinary smokeless nitro-powder. A shrapnel on somewhat similar lines has been made by Ehrhardt; in form (fig. 11) it is an ordinary shrapnel with base burster, but near the head is a second magazine filled with a high-explosive charge; this is attached to the end of the fuze and is so arranged that when the shell is burst as time shrapnel the flash from the fuze passes clear of the high-explosive magazine and ignites only the base magazine, the bullets being blown out in the usual manner. When, however, the fuze acts on graze, the percussion part detonates the high-explosive charge and the bullets are blown out sideways and thus reach men behind shields, &c. (fig. 10). There is some loss of bullet capacity in this shell, and it appears likely that the bullets will be materially deformed when detonation occurs; the advantages may, however, counterbalance their objections.

Segment and ring shell are varieties of shrapnel, the interior of the shell being built up of cast-iron segments or rings (which break up into segments) about a tinned-iron cylinder which formed the magazine of the shell. The shell was completed by a cast-iron body formed around the segments or rings. The German army in 1870 employed ring shell almost exclusively against the French. The French found that common shell (obus ordinaire) when made of cast iron broke up on bursting into a small number of irregularly shaped pieces, and in order to obtain a systematic fragmentation for small shells they adopted a variety of projectiles of the segment and shrapnel types. With the improvements made latterly these have become obsolete, and the French system does not now materially differ from that employed in England and other countries. The old shell are, however, of sufficient interest to be enumerated; thus the "double-walled shell" (obus a double parol) was built up of two shells, the internal portion had a cylindrical chamber for the bursting charge, but on the outside it was so shaped as to break up into well-defined pieces; the external portion of the shell was cast around the internal part, and also broke up into a number Of pieces; this shell was liable to premature explosion. The obus a couronnes de balles (1879) was practically a segment shell with cast-iron balls in lieu of segments; thin iron partitions separated each layer, and the balls were flattened where they came in contact with the plates. The obus a balles libres, adopted in 1880, were of the same type, but there were no separating plates. The obus a anneaux was simply a ring shell of the same type as used in England. The obus a mitraille adopted in 1883 for field and siege guns had a cast-iron disc for its base with the body built up of segments and steel balls; a hollow ogival head surmounted this and a thin steel envelope bound all together. The head was filled with powder and fitted with a fuze; on explosion the head burst and rupturing the envelope set free the balls and segments.

It is of importance in firing shrapnel shell that the position of the burst shall be plainly seen. With the larger patterns of shell this presents no difficulty, but with the shrapnel for field guns which contain a small bursting charge only, and at long range in certain states of the atmosphere, the difficulty becomes pronounced. The problem has been solved in some cases by packing the bullets in fine grain black powder (instead of resin) and compressing both bullets and powder in order to prevent the generation of heat when the bullets set back on the discharge of the gun. In Germany a mixture of red amorphous phosphorus and fine grain powder is used for the same purpose and produces a dense white cloud of smoke. In Russia a mixture of magnesium and antimony sulphide is used.

Fuzes.--The fuzes first used were short iron or copper tubes filled with slow-burning composition. They were roughly screwed on the exterior to fit a similar thread in the fuze hole of the shell. There was no means of regulating the length of time of burning, but later, about the end of the 17th century, the fuze case was made of paper or wood, so that, by boring a hole through the outer casing into the composition, the fuze could be made to burn approximately for a given time before exploding the shell--or the fuze could be cut to the correct length for the same purpose.

Early attempts to produce percussion fuzes were unsuccessful, but the discovery of fulminate of mercury in 1799 finally afforded the means of attaining this object. Some fifty years, however, elapsed before a satisfactory fuze was made. This was the Pettman fuze, in which a roughened ball covered with detonating composition was released by the discharge of the gun. When the shell hit any object, the ball struck against the interior walls of the fuze, the composition was exploded and thence the bursting charge of the shell. At present there are three types of percussion fuzes--(1) those which depend on the gas pressure in the gun setting the pellet of the fuze free--this type is necessarily a base fuze; (2) those which rely on the shock of discharge or the rotation of the shell setting the pellet free, as in various kinds of nose and base fuzes; (3) those relying on direct impact with the object.

The British base percussion fuze (fig. 12) illustrates type (1). In this, before firing, the needle pellet is held back by a central spindle with a pressure plate attached to its rear end. For additional safety a centrifugal bolt is added which is released by the rotation of the shell. On discharge, the gas pressure pushes the pressure plate in, the central spindle is carried forward with it and unlocks the centrifugal bolt; this is withdrawn by the rotation of the shell, and the needle pellet is then free to move forward and explode the detonating cap when the shell strikes.

Type (2) is that usually adopted in small base fuzes and in the percussion part of "time and percussion" fuzes. Here the ferrule, on shock of discharge, moves back relatively to the percussion pellet by collapsing the stirrup spring; this leaves the pellet free to move forward, on the shell striking, and its detonator to strike the needle fixed in the fuze body. A spiral spring prevents any movement of the pellet during flight.

The direct-action or impact fuzes of type (3) are very simple (see fig. 13 of direct-action fuze). They are made of such a strength that during discharge nothing happens, but on striking an object the needle disc is crushed in and the needle explodes the detonating composition and thence the powder.

The action of all time fuzes is started by the discharge of the gun. By this the pellet strikes the detonator and so ignites a length of slow-burning composition which is pressed into a wood tube or into a channel formed in a metal ring. To regulate the time of burning of the wood fuze, a hole is bored through into the composition as before stated, so that when it has burnt down to this hole one of the side channels filled with powder is ignited and explodes the shell. Wood fuzes are now only used for R.M.L. guns.

With modern long-burning fuzes (fig. 14), two composition time rings are used. The lower of these rings is made movable so that it can be turned to bring any desired place over a hole in the body of the fuze, which is filled with powder and communicates with the magazine. On the gun being fired the detonator is exploded and its flash ignites the upper time ring. This burns round to a passage made in the lower ring, when the lower ring begins to burn and continues to do so until the channel to the magazine is reached. The gases from the ignited composition escape from an external hole made in each time ring.

Mechanical time fuzes depending on the rotation of the shell to give a regular motion to clockwork have been tried, but so far no practicable form of these fuzes has been found.

It is important that all fuzes should be rigidly guarded against dampness, which tends to lengthen their time of burning; hence they are protected either by being kept in hermetically sealed tins holding one or more fuzes, or by some similar means.

Tubes and Primers.--In ancient times various devices were adopted to ignite the charge. Small guns were fired by thrusting a hot wire down the vent into the charge, or slow-burning powder was poured down the vent and ignited by a hot wire. Later the priming powder was ignited by a piece of slow match held in a lint-stock (often called linstock). About A.D. 1700 this was effected by means of a port-fire (this was a paper case about

FIG. 14.--Fuze, Time and Percussion, No. 80, Mk. I

16 in. long filled with slow-burning composition which burnt rather more than 1 in. per minute). Later again the charge was exploded by paper tubes (sometimes called Dutch tubes) filled with powder and placed in the vent and ignited by a port- fire. In comparatively modern times friction tubes have been used, while in the latest patterns percussion or electric tubes are employed.

In most B.L. guns it is essential to stop the erosion of the metal of the vent by preventing the escape of gas through it when the gun is fired. For this purpose the charges in such guns are ignited by ``vent-sealing tubes.'' For M.L. guns and small B.L. guns radially vented, especially those using black powder, the amount of erosion in the vent is not so serious. The charge is fired by ordinary friction tubes, which are blown away by the escape of gas through the vent. In all guns axially vented, vent- sealing tubes, which are not blown out, must be employed so that the men serving the gun may not be injured.

The common friction tube is a copper tube, driven with powder, having at the upper end a short branch (called a nib piece) at right angles. This branch is filled with friction composition in which a friction bar is embedded. On the friction bar being sharply pulled out, by means of a lanyard, the composition is ignited and sets fire to the powder in the long tube; the flash is conveyed through the vent and explodes the gun charge. For

FIG. 15.--T-headed Friction Tube.

naval purposes, in order that the sailors should not be cut about the face or hurt their feet, tubes of quill instead of copper were used. If friction tubes are employed when cordite or other smokeless powder charges are used, the erosion of the vent is very rapid unless the escape of the gas is prevented; in this case T-headed tubes (fig. 15) are used. They are similar in action to the ordinary type, but are fixed to the vent by the head fitting a bayonet joint formed with the vent. The explosion blows a small

FIG. 16.--Electric Tube.

ball upwards and blocks the coned hole at the top of the tube and so prevents any rush of gas.

The vent-sealing tube accurately fits into a chamber formed at the end of the vent, and is held in place by the gun lock or some similar means. The force of the explosion expands the tube against the walls of its chamber, while the internal structure of the tube renders it gas-tight, any escape of gas through the vent being thus prevented.

In the English service electric tubes (in the United States called ``primers'') are mostly used, but percussion or friction tubes are in most favour on the continent, and electric tubes are seldom or never used. There are two types of electric tube, one with long wires (fig. 16) for joining

FIG. 17.--Wireless Tube.

up with the electric circuit and the other without external wires. The first type has two insulated wires led into the interior and attached to two insulated brass cones which are connected by a wire ``bridge'' of platinum silver. This bridge is surrounded by a priming composition of guncotton dust and mealed powder and the remainder of the tube is filled with powder. On an electric current passing, the bridge is heated to incandescence and ignites the priming composition.

In the wireless tube (fig. 17) the lock of the gun makes the electric contact with an insulated disc in the head of the tube. This disc is connected by an insulated wire to a brass cone, also insulated, the bridge being formed from an edge of the cone to a brass wire which is soldered to the mouth of the tube. Priming composition surrounds the bridge and the tube is filled with powder. The electric circuit passes from the gun lock to the disc, thence through the bridge to the body of the tube, returning through the metal of the gun and mounting.

The percussion tube (fig. 18) has a similarly shaped body to the wireless electric tube, but the internal construction differs; it is fitted with a striker, below which is a percussion cap on a hollow brass anvil, and the tube is filled with powder.

With Q.F. guns (that is, strictly, those using metallic cartridge cases) the case itself is fitted with the igniting medium; in England these are called primers. For small guns the case contains a percussion primer, usually a copper cap filled with a chlorate mixture and resting against an anvil. The striker of

FIG. 18.--Primer.

the gun strikes the cap and fires the mixture. For larger guns an electric primer (fig. 19) is used, the internal construction and action of which are precisely similar to the wireless tube already described; the exterior is screwed for the case. For percussion

FIG. 19.--Electric Primer.

firing an ordinary percussion tube is placed in an adapter screwed into the case. In some foreign services a combined electric and percussion primer is used; the action of this will be understood from fig. 20.

The first cartridges for cannon were made up of gunpowder packed in a paper bag or case. For many years after the introduction of cannon the powder was introduced into the bore by means of a scoop-shaped ladle fixed to the end of a long stave. The ladle was made of the same diameter as the shot, and it had a definite length so that it was filled once for the charging of small guns but for larger guns the ladle had to be filled twice or even thrice. The rule was to make the powder charge the same weight as that of the shot.

Cartridges made up in paper or canvas bags were afterwards used in forts at night-time or on board ship, so that the guns could be more rapidly loaded and with less risk than by using a ladle. Before loading, a piece of the paper or canvas covering had to be cut open immediately under the vent; after the shot had been rammed home

FIG. 20.--Combined Primer.

the vent was filled with powder from a priming horn, and the gun was then fired by means of a hot iron, quick match or port-fire.

The ancient breech-loading guns were not so difficult to load, as the powder chamber of the gun was removable and was charged by simply filling it up with powder and ramming a wad on top to prevent the escape of the powder.

Paper, canvas and similar materials are particularly liable to smoulder after the gun has been fired, hence the necessity of well sponging the piece. Even with this precaution accidents often occurred owing to a cartridge being ignited by the still glowing debris of the previous round. In order to prevent this, bags of non-smouldering material, such as flannel, serge or silk cloth are used; combustible material such as woven gun-cotton cloth has also been tried, but there are certain disadvantages attending this.

All smokeless powders are somewhat difficult to ignite in a gun, so that in order to prevent hang-fires every cartridge has a primer or igniter, of ordinary fine grain gunpowder, placed so as to intercept the flash from the tube; the outside of the bag containing this igniter is made of shalloon, to allow the flash to penetrate with ease. The charge for heavy guns (above 6 in.) is made up in separate cartridges containing half and quarter charges, both for convenience of handling, and to allow of a reduced charge being used.

The cartridges are made of a bundle of cordite,or other smokeless powder, tightly tied with silk, placed in a silk cloth bag with the primer or igniter stitched on the unclosed end; the exterior is taped with silk cloth tape so as to form a stiff cartridge. For

FIG. 21.--10-inch B.L. Gun Cartridge.

some of the longer guns, the exterior of the cartridre is conveniently made of a coned shape, the coned form being produced by building up layers outside a cylindrical core. In these large cartridges a silk cord becket runs up the centre with a loop at the top for handling (fig. 21).

For howitzers, variable charges are used, and are made up so that the weight can be readily altered. The following typical instance (fig. 22) will serve to show the general method of making

Fig. 22.--6-inch B.L. Howitzer Cartridge.

such charges, whether for B.L. or Q.F. howitzers. Small size cordite is used, and the charge is formed of a mushroom-shaped core, made up in a shalloon bag; on the stalk, so as to be easily removed, three rings of cordite are placed. The bottom of the core contains the primer, and the rings can be attached to the core by two silk braids. The weight of the rings is graduated so that by detaching one or more the varying charges required can be obtained.

For quick-firing guns the charge is contained in a brass case to which is fitted a primer for igniting the charge. This case is inserted into the gun, and when fired slightly expands and tightly fits the chamber of the gun, thus acting as an obturator and preventing any escape of gas from the breech. This class of ammunition is especially useful for the smaller calibres of guns, such as 3-pr., 6-pr. and field guns, but Messrs Krupp also employ metallic cartridge cases for the largest type of gun, probably on account of the known difficulty of ensuring trustworthy obturation by any other means practicable with sliding wedge guns.

The charges for these cases are made up in a very similar manner to those already described for B.L. guns. Where necessary, distance pieces formed of papier-mache tubes and felt wads are used to fill up the space in the case and so prevent any movement of the charge. The mouth of the case is closed either by the base end of the projectile (fig. 23), in which case it is called ``fixed ammunition'' or ``simultaneous loading ammunition.'' or by a metallic cap (fig. 24), when it is called ``separate

FIG. 24.--4.7-inch Q.F. Cartridge greatly reduced scale).

loading ammunition,'' projectile and charge being thus loaded by separate operations. (A. G. H.)

The Bullet.--The original musket bullet was a spherical leaden ball two sizes smaller than the bore, wrapped in a loosely fitting paper patch which formed the cartridge. The loading was, therefore, easy with the old smooth-bore Brown Bess and similar military muskets. The original muzzle-loading rifle, on the other hand, with a closely fitting ball to take the grooves, was loaded with difficulty, particularly when foul, and for this reason was not generally used for military purposes.

In 1826 Delirque, a French infantry officer, invented a breech with abrupt shoulders on which the spherical bullet was rammed down until it expanded and filled the grooves. The objection in this case was that the deformed bullet had an erratic flight. The Brunswick rifle, introduced into the British army in the reign of William IV., fired a spherical bullet weighing 557 grs. with a belt to fit the grooves. The rifle was not easily loaded, and soon fouled. In 1835 W. Greener produced a new expansive bullet, an oval ball, a diameter and a half in length, with a flat end, perforated, in which a cast metallic taper plug was inserted. The explosion of the charge drove the plug home, expanded the bullet, filled the grooves and prevented windage. A trial of the Greener bullet in August 1835, at Tynemouth, by a party of the 60th (now King's Royal) Rifles, proved successful. The range and accuracy of the rifle were retained, while the loading proved as easy as with a smooth-bore musket. The invention was, however, rejected by the military authorities on the ground that the bullet was a compound one. In 1852 the government awarded Minie, a Frenchman, L. 20,000 for a bullet of the same principle, adopted into the British service. Subsequently, in 1857, Greener was also awarded L. 1000 for ``the first public suggestion of the principle of expansion, commonly called the Minie principle, in 1836.'' The Minie bullet contained an iron cup in a cavity in the base of the bullet. The form of the bullet was subsequently changed from conoidal to cylindro-conoidal, with a hemispherical iron cup. This bullet was used in the Enfield rifle introduced into the British army in 1855. It weighed 530 grs., and was made up into cartridges and lubricated as for the Minie rifle. A boxwood plug to the bullet was also used. The bullet used in the breech-loading Martini-Henry rifle, adopted by the British government in 1871 in succession to the Snider-Enfield rifle, weighed 480 grs., and was fired from an Eley-Boxer cartridge- case with a wad of wax lubrication at the base of the bullet.

Between 1854 and 1857 Sir Joseph Whitworth conducted a long series of rifle experiments, and proved, among other points, the advantages of a smaller bore and, in particular, of an elongated bullet. The Whitworth bullet was made to fit the grooves of the rifle mechanically. The Whitworth rifle was never adopted by the government, although it was used extensively for match purposes and target practice between 1857 and 1866, when it was gradually superseded by Metford's System mentioned below.

The next important change in the history of the rifle bullet occurred in 1883, when Major Rubin, director of the Swiss Laboratory at Thun, invented the small-calibre rifle, one of whose essential features was the employment of an elongated compound bullet, with a leaden core in a copper envelope. About 1862 and later, W. E. Metford had carried out an exhaustive series of experiments on bullets and rifling, and had invented the important system of light rifling with increasing spiral, and a hardened bullet. The combined result of the above inventions was that in December 1888 the Lee-Metford small-bore .303 rifle, Mark I., was finally adopted for the British army. The latest development of this rifle is now known as the .303 Lee-Enfleld, which fires a long, thin, nickel-covered, leaden-cored bullet 1.25 in. long, weighing only 215 grs., while the Martini-Henry bullet, 1.27 in. in length and .45 in. in diameter, weighed 480 grs.

The adoption of the smaller elongated bullet, necessitated by the smaller calibre of the rifle, entailed some definite disadvantages. The lighter bullet is more affected by wind. Its greater relative length to diameter necessitates a sharper pitch of rifling in order properly to revolve the bullet (one turn in 10 in. for the .303 rifle as compared with one turn in 22 in. for the Martini-Henry). This, in its turn, necessitates a hard nickel envelope for the leaden bullet in order to prevent its ``stripping,'' or being forced through the barrel without rotation. The general result is that, while the enveloped bullet has a much higher penetrative power than one of lead only, it does not usually inflict so severe a wound, nor has it such a stunning effect as the old lead bullet. It cuts a small clean hole, but does not deform. This fact is of some military importance, as, for example, in warfare with savages, in which the chief danger is usually a rush of large numbers at close quarters. The advantages, however, of the smaller calibre and the lighter bullet and ammunition are considered to outweigh the disadvantages, and they have been universally adopted for all military rifles.

Bullets for target and sporting-rifles have, in the main, followed, or occasionally preceded, the line of progress of military rifle bullets. In 1861 Henry introduced a modification of the grooving of the cylindrical Whitworth bullet, and in 1864 and 1865 the Rigby mechanically fitting bullet was used with success at the National Rifle Association meeting, and in the second stage of the Queen's prize. The bullets of sporting rifles, and particularly those of Express rifles, are often lighter than military bullets, and made with hollow points to ensure the expansion of the projectile on or after impact. The size and shape of the hollow in the point vary according to the purpose required and the nature of the game hunted. If greater penetration is needed, the leaden bullet is hardened with mercury or tin, or the military nickel-coated bullet is used with the small-bore, smokeless- powder rifles. Explosive bullets filled with detonating powder were at one time used in Express and large-bore rifles for large game. The use of these bullets is now practically abandoned owing to their uncertainty of action and the danger involved in handling them. Their use in warfare is prohibited by international law.

The nickel-covered bullet, when used in a modern small-bore rifle for sporting purposes, is made into an expanding bullet, either by leaving the leaden core uncovered at the nose of the bullet, with or without a hollow point, or by cutting transverse or longitudinal nicks of varying depth in the point or circumference of the bullet.

A cone-shaped sharp-pointed bullet, named the Spitzer bullet, has been tried in the United States under the auspices of the Ordnance Department, in a Springfield rifle, which is practically identical with the British service .303 Lee-Enfield. This bullet is lighter than the Lee-Enfield bullet (150 grs. as against 215 grs.), and when fired with a heavier charge of powder (51 grs. as against 31 grs.) gives, it is claimed, better results in muzzle-velocity, trajectory, deflexion from wind and wear and tear of rifling, than the present universally used cylinder-shaped bullet. In 1906 details of its prototype, the German ``S'' bullet (Spitzgeschoss), and of the French ``D'' bullet, were published.

The Cartridge.--The original cartridge for military small arms dates from 1586. It consisted of a charge of powder and a bullet in a paper envelope. This cartridge was used with the muzzle- loading military firearm, the base of the cartridge being ripped or bitten off by the soldier, the powder poured into the barrel, and the bullet then rammed home. Before the invention of the firelock or flint-lock, about 1635, the priming was originally put into the pan of the wheel-lock and snaphance muskets from a flask containing a fine-grained powder called serpentine powder. Later the pan was filled from the cartridge above described before loading. The mechanism of the flint-lock musket, in which the

FIG. 25.

pan was covered by the furrowed steel struck by the flint, rendered this method of priming unnecessary, as, in loading, a portion of the charge of powder passed from the barrel through the vent into the pan, where it was held by the cover and hammer.

The next important advance in the method of ignition was the introduction of the copper percussion cap. This was only generally applied to the British military musket (the Brown Bess) in 1842, a quarter of a century after the invention of percussion powder and after an elaborate government test at Woolwich in 1834. The invention which made the percussion cap possible was patented by the Rev. A. J. Forsyth in 1807, and consisted of priming with a fulminating powder made of chlorate of potash, sulphur and charcoal, which exploded by concussion. This invention was gradually developed, and used, first in a steel cap, and then in a copper cap, by various gunmakers and private individuals before coming into general military use nearly thirty years later. The alteration of the military flint-lock to the percussion musket was easily accomplished by replacing the powder pan by a perforated nipple, and by replacing the cock or hammer which held the flint by a smaller hammer with a hollow to fit on the nipple when released by the trigger. On the nipple was placed the copper cap containing the detonating composition, now made of three parts of chlorate of potash, two of fulminate of mercury and one of powdered glass. The detonating cap thus invented and adopted, brought about the invention of the modern cartridge case, and rendered possible the general adoption of the breech-loading principle for all varieties of rifles, shot guns and pistols. Probably no invention connected with firearms has wrought such changes in the principle of gun construction as those effected by the expansive cartridge case. This invention has completely revolutionized the art of gunmaking, has been successfully applied to all descriptions of firearms, and has produced a new and important industry--that of cartridge manufacture.

Its essential feature is the prevention of all escape of gas at the breech when the weapon is fired, by means of an expansive cartridge case containing its own means of ignition. Previous to this invention shot guns and sporting rifles were loaded by means of powder flasks and shot flasks, bullets, wads and copper caps, all carried separately. The earliest efficient modern cartridge case was the pin-fire, patented, according to some authorities, by Houiller, a Paris gunsmith, in 1847; and, according to others, by Lefaucheux, also a Paris gunsmith, in or about 1850. It consisted of thin weak shell made of brass and paper which expanded by the force of the explosion, fitted perfectly into the barrel, and thus formed an efficient gas check. A small percussion cap was placed in the middle of the base of the cartridge, and was exploded by means of a brass pin projecting from the side and struck by the hammer. This pin also afforded the means of extracting the cartridge case. This cartridge was introduced in England by Lang, of Cockspur Street, London, about 1855.

The central-fire cartridge was introduced into England in 1861 by Daw. It is said to have been the invention of Pottet of Paris, improved upon by Schneider, and gave rise to much litigation in respect of its patent rights. Daw was subsequently defeated in his control of the patents by Eley Bros. In this cartridge the cap in the centre of the cartridge base is detonated by a striker passing through the standing breech to the inner face, the cartridge case being withdrawn, or, in the most modern weapons, ejected by a sliding extractor fitted to the breech end of the barrel, which catches the rim of the base of the cartridge.

This is practically the modern cartridge case now in universal use. In the case of shot guns it has been gradually inproved in small details. The cases are made either of paper of various qualities with brass bases, or entirely of thin brass. The wadding between powder and shot has been thickened and improved in quality; and the end of the cartridge case is now made to fit more perfectly into the breech chamber. These cartridges vary in size from 32 bore up to 4 bore for shoulder guns. They are also made as small as .410 and .360 gauge: their length varies from 1 3/4 in. to 4 in. Cartridges for punt guns are usually 1 1/2 in. in diameter and 9 3/4 in. in length.

In the case of military rifles the breech-loading cartridge case was first adopted in principle by the Prussians about 1841 in the needle-gun (q.v.) breech-loader. In this a conical bullet rested on a thick wad, behind which was the powder, the whole being enclosed in strong lubricated paper. The detonator was in the hinder surface of the wad, and fired by a needle driven forward from the breech, through the base of the cartridge and through the powder, by the action of a spiral spring set free by the pulling of the trigger.

In 1867 the British war office adopted the Eley-Boxer metallic central-fire cartridge case in the Enfield rifles, which were converted to breech-loaders on the Snider principle. This consisted of a block opening on a hinge, thus forming a false breech against which the cartridge rested. The detonating cap was in the base of the cartridge, and was exploded by a striker passing through the breech block. Other European powers adopted breech-loading military rifles from 1866 to 1868, with paper instead of metallic cartridge cases. The original Eley-Boxer cartridge case was made of thin coiled brass. Later the solid-drawn, central-fire cartridge case, made of one entire solid piece of tough hard metal, an alloy of copper, &c., with a solid head of thicker metal, has been generally substituted.

Central-fire cartridges with solid-drawn metallic cases containing their own means of ignition are now universally used in all modern varieties of military and sporting rifles and pistols. There is great variety in the length and diameter of cartridges for the different kinds and calibres of rifles and pistols. Those for military rifies vary from 2.2 in. to 2.25 in. in length, and from .256 to .315 gauge. For sporting rifles from 2 1/4 in. to 3 1/2 in. in length, and through numerous gauges from .256 in. to .600 in. For revolvers, pistols, rook and rabbit rifles, and for Morris tubes, cartrillges vary from .22 in. to .301 in. in gauge. All miniature cartridges with light charges are made for breech adapters to enable .303 military rifles to be used on miniature rifle ranges. All the above cartridges are central-fire. Rim-fire cartridges for rifles, revolvers and pistols vary from .22 in. to .56 in. gauge according to the weapon for which they are required. The cartridge for the British war office miniature rifle is .22 calibre, with 5 grs. of powder and a bullet weighing 40 grs. Most modern military rifles are supplied with clip or charger loading arrangements, whereby the magazine is filled with the required number of cartridges in one motion. A clip is simply a case of cartridges which is dropped into the magazine; a charger is a strip of metal holding the bases of the cartridges, and is placed over the magazine, the cartridges being pressed out into the latter. Both clips and chargers, being consumable stores, may be considered as ammunition. (H. S.-K.)

AMNESTY (from the Gr. amnestia, oblivion), an act of grace by which the supreme power in a state restores those who may have been guilty of any offence against it to the position of innocent persons. It includes more than pardon, inasmuch as it obliterates all legal remembrance of the offence. Amnesties, which may be granted by the crown alone, or by act of parliament, were formerly usual on coronations and similar occasions, but are chiefly exercised towards associations of political criminals, and are sometimes granted absolutely, though more frequently there are certain specified exceptions. Thus, in the case of the earliest recorded amnesty, that of Thrasybulus at Athens, the thirty tyrants and a few others were expressly excluded from its operation; and the amnesty proclaimed on the restoration of Charles II. did not extend to those who had taken part in the execution of his father. Other celebrated amnesties are that proclaimed by Napoleon on the 13th of March 1815, from which thirteen eminent persons, including Talleyrand, were excepted; the Prussian amnesty of the 10th of August 1840; the general amnesty proclaimed by the emperor Francis Joseph of Austria in 1857; the general amnesty granted by President Johnson after the Civil War in 1868; and the French amnesty of 1905. The last act of amnesty passed in Great Britain was that of 1747, which proclaimed a pardon to those who had taken part in the second Jacobite rebellion.

AMOEBA, the Greek equivalent of the name ``Amibe'' given by Bery St Vincent to the Proteus animalcule of earlier naturalists, used as a quasi-popular term for any simple naked protist the sole external organs of which are pseudopodia, i.e. temporary outgrowths of the clearer outer layer of the soft protoplasmic body. It is also used as a generic name, and in its present limitations by E. Penard includes only those the pseudopodia of which are constantly changing, blunt outgrowths. In the former wider sense, amoebae are found in sluggish waters, fresh and salt, all over the world; they readily make their appearance in infusions putrefying after infection from aerially carried germs, and the leucocytes or colourless blood corpuscles of Metazoa are essentially amoebae in their structure and behaviour. The protoplasm of the individual is divided into a centrally placed body, the nucleus, of relatively stable shape, and the cytoplasm, itself divided into an outer, clearer ectoplasm (``ectosarc'') and an inner, more granular endoplasm (``endosarc''), passing into one another. The movements of amoebae are of several kinds. (1) The amoeba may grow out irregularly into blunt lobes, the pseudopodia, some being emitted while others are retracted, and so may advance in any direction by the emission of pseudopodia thitherward, and the enlargement of these by the passage of the organism into them. (2) Again, it may advance by a sort of rolling: the lower surface, or that in contact with the substratum over or under which it is passing, is viscid and adheres to the substratum, the superficial dorsal layer passing forward and bending over to the ventral side; whilst the converse action takes place at the hinder end; (3) or again, the pseudopodia, when long, well marked and relatively permanent, may serve as actual limbs on which the body is supported and on which it moves. In the outgrowth of a pseudopod the process may take place gradually, the ectoplasm growing as it stretches, or it may take place by the limiting layer of the ectosarc bursting, as it were, and a rounded prominence of the endosarc protruding and at once forming a new ``skin', or pellicle. This last mode, termed ``eruptive,'' is common in the case of the enormous, multinucleate amoeba termed Pelomyxa palustris, which attains a diameter when contracted and spherical of as much as a line (over 2 mm.). From the ease with which amoebae are obtained and kept alive under the microscope, as well as from their identity in structure with the primitive elements of Metazoa, they have always been favourite objects of study for protoplasmic physiology under its simplest conditions. Among the investigators of protoplasmic movements we may cite F. Dujardin, O. Butschli, L. Rhumbler and H. S. Jennings. The opening to the exterior of the contractile vesicle has been found here. Pelomyxa has yielded to A. E. Dixon and M. Hartog a peptic ferment, such as has been extracted by C. F. W. Krukenberg from the myxomycete Fuligo (Flowers of Tan), which is the largest known naked mass of protoplasm without cellular differentiation.

Amoeba shows also the multiplication by fission, so characteristic of the cell: for the study of other modes of reproduction, spore formation and syngamic (or so-called fertilization) processes, fresh-water or salt-water amoebae are ill suited, and up to this date we do not know the life cycle of any free-living naked amoeba, though that of some parasitic forms and shell-bearers have been fully made out. Some amoebae are certainly young states of Myxomycetes. Encystment, the excretion of a membrane around the cell to tide over unfavourable circumstances, has been noted in almost all species.

Amoeba coli and A. histolytica are parasites in the gut of man, the former relatively harmless, the latter the cause of severe dysentery and hepatic abscess, common in India.

H. S. Jennings has recently made a full study of the movements of Amoeba, and of its general behaviour, and found therein many indications that these are on the whole such as we should expect of an organism working by ``trial and error'' rather than the uniform modes of non-living beings. Thus the operations of an amoeba ingesting a round, encysted Euglena are summed up thus: ``One seems to see that the amoeba is trying to obtain this cyst for food, that it shows remarkable pertinacity in continuing its attempts to put forth efforts to accomplish this in various ways, and that it shows remarkable pertinacity in continuing its attempts to ingest the food when it meets with difficulties. Indeed the scene could be described in a much more vivid and interesting way by the use of terms still more anthropomorphic in tendency.'' (M. HA.)

AMOL, or AMUL, a town of Persia, in the province of Mazandaran, 23 m. W. of Barfurush, in 36 deg. 28' N. Lat. and 52 deg. 23' E. long. Pop. about 10,000. It is situated on both banks of the Heraz, or Herhaz river, which is crossed here by a very narrow stone bridge of twelve arches and flows into the Caspian Sea 12 m. lower down. Amol is not walled and is now a place of little importance, but in and around it there are ruins and ancient buildings which bear witness to its former greatness. Of these the most conspicuous is the mausoleum of Seyed Kavvam ud-din, king of Mazandaran, who died in 1379, and one old mosque dates from A.D. 793. The town has spacious and well-supplied bazaars and post and telegraph offices.

AMONTONS, GUILLAUME (1663-1705), French experimental philosopher, the son of an advocate who had left his native province of Normandy and established himself at Paris, was born in that city on the 31st of August 1663. He devoted himself particularly to the improvement of instruments employed in physical experiments. In 1687 he presented to the Academy of Sciences an hygrometer of his own invention, and in 1695 he published his only book, Remarques et experiences physiques sur la construction d'une nouvelle clepsydre, sur les barometres, les thermometres et les hygrometres. In 1699 he published some investigations on friction, and in 1702-1703 two noteworthy papers on thermometry. He experimented with an air-thermometer, in which the temperature was defined by measurement of the length of a column of mercury; and he pointed out that the extreme cold of such a thermometer would be that which reduced the ``spring'' of the air to nothing, thus being the first to recognize that the use of air as a thermometric substance led to the inference of the existence of a zero of temperature. In 1704 he noted that barometers are affected by heat as well as by the weight of the atmosphere, and in the following year he described barometers without mercury, for use at sea. Amontons, who through disease was rendered almost completely deaf in early youth, died at Paris on the 11th of October 1705.

'AMORA (Hebrew for ``speaker'' or ``discourser''), a title applied to the rabbis of the 2nd to 5th centuries, i.e. to the compilers of the Talmud. Each tana--or rabbi of the earlier period--had a spokesman, who repeated to large audiences the discourses of the tana. But the 'amora soon ceased to be a mere repeater, and developed into an original expounder of scripture and tradition.

AMORITES, the name given by the Israelites to the earlier inhabitants of Palestine. They are regarded as a powerful people, giants in stature ``like the height of the cedars,'' who had occupied the land east and west of the Jordan. The Biblical usage appears to show that the terms ``Canaanites'' and ``Amorites'' were used synonymously, the former being characteristic of Judaean, the latter of Ephraimite and Deuteronomic writers. A distinction is sometimes maintained, however, when the Amorites are spoken of as the people of the past, whereas the Canaanites are referred to as still surviving. The old name is an ethnic term, evidently to be connected with the terms Amurru and Amar, used by Assyria and Egypt respectively. In the spelling Mar-tu, the name is as old as the first Babylonian dynasty, but from the 15th century B.C. and downwards its syllabic equivalent Amurru is applied primarily to the land extending northwards of Palestine as far as Kadesh on the Orontes. The term ``Canaan,'' on the other hand, is confined more especially to the southern district (from Gebal to the south of Palestine). But it is possible that the terms at an early date were interchangeable, Canaan being geographical and Amorite ethnical. The wider extension of the use of Amurru by the Babylonians and Assyrians is complicated by the fact that it was even applied to a district in the neighbourhood of Babylonia. If the people of the first Babylonian dynasty (about 21st century B.C.) called themselves ``Amorites,'' as Ranke seems to have shown, it is possible that some feeling of common origin was recognized at that early date.

See Ranke, Bab. Exped. Pennsylvania, series D, iii. 33 sqq.; and for general information, W. M. Muller, Asien u. Europa, 217 sqq.; Pinches, Old Testament, Index (s.v..) The people of Amar are represented on the Egyptian monuments with yellow skin, blue eyes, red eyebrows and beard, whence it has been conjectured that they were akin to the Libyans (Sayce, Expositor, July 1888). Senir, the ``Amorite', name of Hermon (Deut. iii. 9). appears to be identical with Saniru in the Lebanon, mentioned by Shalmaneser Il. In the Old Testament the chief references may be classified as follows:--primitive inhabitants generally, Is. xvii. 9 (on text see comm.), Ezek. xvi. 3; a people W. of Jordan, Josh. x. 5; Judg. i. 34-36; Deut. i. 7, 44; Gen. xiv. 7, xlviii. 22: E. of Jordan, Num. xxi. 13, 21 sqq.; Josh. ii. 10, xxiv. 8; Judg. x. 8. See further CANAAN, PALESTINE.

AMORPHISM (from a, privative, and morfe, form), a term used in chemistry and mineralogy to denote the absence of regular or crystalline structure in a body; the adjective ``amorphous,'' formless or of irregular shape, being also used technically in biology, &c.

AMORT, EUSEBIUS (1692--1775), German Catholic theologian, was born at Bibermuhle, near Tolz, in Upper Bavaria, on the 15th of November 1692. He studied at Munich, and at an early age joined the Canons Regular at Polling, where, shortly after his ordination in 1717, he taught theology and philosophy. In 1733 he went to Rome as theologian to Cardinal Niccolo Maria Lercari (d. 1757). He returned to Polling in 1735 and devoted the rest of his life to the revival of learning in Bavaria. He died at Polling on the 5th of February 1775. Amort, who had the reputation of being the most learned man of his age, was a voluminous writer on every conceivable subject, from poetry to astronomy, from dogmatic theology to mysticism. His best known works are: a manual of theology in 4 vols., Theologia electica, moralis et scholastica (Augsburg, 1752; revised by Benedict XIV. for the 1753 edition published at Bologna); a defence of Catholic doctrine, entitled Demonstratio critica religionis Catholicae (Augsburg, 1751); a work on indulgences, which has often been criticized by Protestant writers, De Origine, Progressu, Valore, et Fructu Indulgentiorum (Augsburg, 1735); a treatise on mysticism, De Revelationibus et Visionibus, &c. (2 vols., 1744); and the astronomical work Nova philosophiae planetarum et artis criticae systemata (Nuremberg, 1723). The list of his other works, including his three erudite contributions to the question of authorship of the Imitatio Christi, will be found in C. Toussaint's scholarly article in A. Vacant's Dict. de theologie (1900, cols. 1115-1117).

AMORTIZATION (derived through the French from Lat. ad, and mortem, to death), literally an extinction or doing to death, a word formerly used of alienating lands in mortmain, and now for the paying off of a debt, particularly by means of a regular sinking-fund; thus ``amortization'' and ``amortization fund'' generally refer to the latter method of extinguishing some pecuniary liability.

AMORY, THOMAS (c. 1691-1788), British author, was born about 1601, his father being the secretary for the forfeited estates in Ireland. He was an eccentric character and seems to have lived a very secluded life. He published Memoirs; containing the lives of several Ladies of Great Britain; a History of Antiquities &c. (1755) and Life of John Buncle Esq. (1756 and 1766). Both books are an extraordinary mixture of fiction, autobiography, scenic description and theological discussion. Amory died on the 25th of November 1788.

AMOS, in the Bible, an Israelitish prophet of the 8th century B.C. He was a native of Tekoa, i.e. as most suppose, a place which still bears the same name 6 m. S. of Bethlehem. He was a shepherd, or perhaps a sheep-breeder, but combined this occupation with that of a tender of sycomore figs. It is true, the Tekoa just mentioned lies too high for sycomores; so it has been almost too ingeniously supposed that Amos may have owned a plantation of sycomores in the hill country leading down to Philistia, technically called the Shephelah (R. Y., ``lowland''). Here there were sycomores in abundance (1 Kings x. 27). That this was his usual occupation we learn from a better source than the heading (i. 1), viz. a narrative (vii. 10, 17), evidently of early origin, which interrupts the series of prophetic visions on the fall of the kingdom of Israel. Amos, it appears, though himself a Judahite, had been prophesying in the northern kingdom, when his activity was brought to an abrupt close by the head priest of the royal sanctuary at Bethel, Amaziah, who bade him escape to the land of Judah and get his living there. The reply of Amos is full of instruction. ``No prophet am I; no prophet's son am I; a shepherd am I, and one who tends sycomore-figs. And Yahweh took me from behind the flock; and Yahweh said to me, Go, prophesy against my people Israel.'' The following words show that a prophet in ancient Israel had the utmost freedom of speech. It was far otherwise in the period of the fall of Judah. (See JEREMIAH.)

But what had Amos said that appeared so dangerous to the head priest? Amaziah summarizes it thus, ``Jeroboam shall die by the sword, and Israel shall go away into captivity from his own land'' (vii. 11; cf. vii. 9b, v. 27, vi. 7). He omits all the reasons for this stern prophecy. The reasons are that the good old Israelitish virtue of brotherliness is dying away, that oppression and injustice are rampant (ii. 6-8, iii. 9, 10, iv. 1, v. 11, 12, viii. 4-6), and that rites are practised in the name of religion which are abhorrent to Yahweh, because they either have no moral meaning at all, and are mere forms (v. 21-23), or else, jndged from Amos's purified point of view, are absolutely immoral (ii. 7; cf. viii. 14). On the details of the captivity Amos preserves a mysterious vagueness. The fact, however, he puts forward with the confidence of one who is intimate with his God (iii. 7), and most probably it was at some great festival that he spoke the words which so perturbed Amaziah. The priest may not indeed himself have believed them, but he probably feared their effect on the moral courage of the people. And it is perhaps not arbitrary to suppose that the splendour of the ritual in Amos's time implies a tremulous anxiety that Israel's seeming prosperity under Jeroboam II. (see JEWS) may not be as secure as could be wished. For Amos cannot have been quite alone either in Israel or in Judah; there must have been a little flock of those who felt with Amos that there was small reason indeed to ``desire the day of Yahweh'' (v. 18; see Harper's note).

But why did Amos so emphatically decline to be called a prophet? A prophet in some true sense he certainly was, a prophet who, within his own range, has not been surpassed. He means this--that he is no mere ecstatic enthusiast or ``dervish,'' whose primary aim is to keep up the warlike spirit of the people, taking for granted that Yahweh is on the people's side, and that he is perfectly free from the taint of selfishness, not having to support himself by his prophesying. He could not indeed tell Amaziah this, but it is nevertheless true that he was the founder, or one of the founders, of a new type of prophet. He was also either the first, or one of the first, to write down, or to get written down, the substance of his spoken prophecies, and perhaps also prophecies which he never delivered at all. This was the consequence of his ill success as a public preacher. The other prophets of the same order may be presumed to have been hardly less unsuccessful. Hence the new phenomenon of written prophecies. The literary skill of Amos leads one to suppose that he had prepared in advance for this, perhaps we may say, not altogether unfortunate necessity.

That there are many hard problems connected with the fascinating book of Amos cannot be denied. The one point on which we have indicated a doubt, viz. as to the situation of Tekoa, ought strictly to be accompanied by others. For instance, how came Amos to transfer himself to northern Israel? How hard it must have been to obtain a footing there while he was a mere student and observer! And how came he by his wide knowledge of people outside the limits of Israel? The most recent and elaborate commentator even calls him an ``ethnologist.'' And lastly, whence came his mastery of the poetical and literary arts? Is he really the Columbus of written prophecy? And behind these questions is the fundamental problem of the text, which has been somewhat too slightly treated. The text of Hosea may be in a much worse condition, but a keen scrutiny discloses many an uncertainty, not to say impossibility, in the traditional form of Amos. That the text has been much adapted and altered is certain; not less obvious are the corruptions due to carelessness and accident.

The main divisions of the book are plain, viz. chaps. i.-ii., chaps. iii.-vi., and chaps. vii.-ix. This arrangement, however, is probably not due to Amos himself, or to his immediate disciples, but to some later redactor. A number of passages seem to have been inserted subsequently to the time of Amos, on which see Ency. Bib., ``Amos,'' and the introduction to Robertson Smith's Prophets of Israel(2), though in some cases the final decision will have to be preceded by a more thorough examination of the traditional text. The most obvious non-Amosian passage in the book is the concluding passage, ix. 8-15, which has evidently supplanted the original close of the section. The meaning of the phrase ``the tabernacle (booth) of David that is fallen'' (ver. 11) is not perfectly clear. Beyond reasonable doubt, however, the writer seeks to take out the sting of the preceding passage in which Israel is devoted to utter destruction. The penitent and God-fearing Jews of the post-exilic age needed some softening appendix, and this the editor provided.

English readers are now well supplied with books on Amos. Driver's Joel and Amos (see JOEL) (1897) and G. A. Smith's Twelve Prophets, vol. i. (1896), supplement and illustrate each other. Harper's Amos anid Hosea (see HOSEA) (1905) gives the cream of all the good things that have been said before, with a generally sound judgment; it is addressed to advanced students, and is perhaps less cautious than the two former. The German commentaries on the Minor Prophets by Nowack (2nd ed., 1905) and (especially) Marti (1904) must not, however, be neglected. Wellhausen's briefer work (3rd ed., 1898) is esriecially suggestive for textual criticism. Cheyne's Critica Biblica (1904), cf. his review of Harper in Hibbert Journal, iii. 824 fl., breaks new ground. (T. K. C.)

AMOS, SHELDON (1835-1886), English jurist, was educated at Clare College, Cambridge, and was called to the bar as a member of the Middle Temple in 1862. In 1869 he was appointed to the chair of jurisprudence in University College, London, and in 1872 became reader under the council of legal education and examiner in constitutional law and history to the university of London. Failing health led to his resignation of those offices, and he took a voyage to the South Seas. He resided for a short time at Sydney, and finally settled in Egypt, where he practised as an advocate. After the bombardment of Alexandria, and the reorganization of the Egyptian judicature, he was appointed judge of the court of appeal, but being without any previous experience of administrative work he found the strain too great for his health. He came to England on leave in the autumn of 1885, and on his return to Egypt he died suddenly at Alexandria on the 3rd of January 1886. His principal publications are: Systematic View of the Science of Jurisprudence (1872); Lectures on International Law (1873); Science of Law (1874); Science of Politics (1883); History and Principles of the Civil Law of Rome as Aid to the Study of Scientific and Comparative Jurisprudence (1883), and numerous pamphlets. His wife, Mrs Sheldon Amos (Sarah Maclardie Bunting), took a prominent part in Liberal Nonconformist politics and in movements connected with the position of women. She died at Cairo on the 21st of January 1908.

AMOY, a city and treaty-port in the province of Fuh-kien, China, situated on the slope of a hill, on the south coast of a small and barren island named Hiamen, in 24 deg. 28' N. and 118 deg. 10' E. It is a large and exceedingly dirty place, about 9 m. in circumference, and is divided into two portions, an inner and an outer town, which are separated from each other by a ridge of hills, on which a citadel of considerable strength has been built. Each of these divisions of the city possesses a large and commodious harbour, that of the inner town, or city proper, being protected by strong fortifications. There are dry-docks and an excellent anchorage. Amoy may be regarded as the port of the inland city of Chang-chow, with which it has river communication, and its trade, both foreign and coastwise, is extensive and valuable. The chief articles imported are sugar, rice, raw cotton and opium, as well as cotton cloths, iron goods and other European manufactures. The chief exports are tea, porcelain and paper. The trade carried on by means of Chinese junks is said to be large, and the native merchants are considered to be among the wealthiest and most enterprising in China. By other vessels the trade in 1870 was:--imports, L. 1,915,427; exports, L. 1,440,000. In 1904 the figures were:--imports, L. 2,081,494; exports, L. 384,494. The falling off of exports is due to the decreased demand for China tea, for which Amoy was one of the chief centres. The native population is now estimated at 300,000, and the foreign residents number about 280. A large part of the trade is that carried on with the neighbouring Japanese island of Formosa. The province of Fuh-kien is claimed by the Japanese as their particular sphere of influence. Amoy was captured by the British in 1841, after a determined resistance, and is one of the five ports that were opened to British commerce by the treaty of 1842; it is now open to the ships of all nations.

AMPELIUS, LUCIUS, possibly a tutor or schoolmaster, and author of an extremely concise summary--a kind of index--of universal history (Liber Memorialis) from the earliest times to the reign of Trajan. Its object and scope are sufficiently indicated in the dedication to a certain Macrinus: ``Since you desire to know everything, I have written this `book of notes,' that you may learn of what the universe and its elements consist, what the world contains, and what the human race has done.'' It seems to have been intended as a text-book to be learnt by heart. The little work, in fifty chapters, gives a sketch of cosmography, geography, mythology (chaps. i.-x.), and history (chap. x.-end). The historical portion, dealing mainly with the republican period, is untrustworthy, and the text in many places corrupt; the earlier chapters are more valuable, and contain some interesting information. In chap. viii. (Miracula Mundi) occurs the only reference in an ancient writer to the famous sculptures of Pergamum, discovered in 1871, excavated in 1878, and now at Berlin: ``At Pergamum there is a great marble altar, 40 ft. high, with colossal sculptures, representing a battle of the giants.'' Nothing is known of the author or of the date at which he lived: the times of Trajan, Hadrian, Antoninus Pius, the beginning of the 3rd century, and the age of Diocletian and Constantine have all been suggested. The Macrinus to whom the work is dedicated may have been the emperor, who reigned 217-218, but the name is not uncommon, and it seems more likely that he was a young man with a thirst for universal knowledge, which the Liber Memorialis was compiled to satisfy.

There is no English edition or translation. The first edition of Ampelius was published in 1638 by Salmasius (Saumaise) from the Dijon MS., now lost, together with the Epitome of Florus; the latest edition is by Wolfflin (1854), based on Salmasius's copy of the lost codex.

See Glaser, Rheinisches Museum, ii. (1843); Zink, Eos, ii (1866); Wolfflin, De L. Ampelii Libro Memoriali (1854).

AMPELOPSIS (from Gr. ampelos, vine, and opsis, appearance, as it resembles the grape-vine in habit), a genus of the vine order Ampelideae and nearly allied to the grape-vine. The plants are rapidly-growing, hardy, ornamental climbers, which flourish in common garden soil, and are readily propagated by cuttings. They climb by means of tendrils. A. quinquefolia, Virginian creeper, a native of North America, introduced to Europe early in the 17th century, has palmately compound leaves with three to five leaflets. A. tricuspidata, better known as A. Veitchii, a more recent introduction (1868) from Japan, has smaller leaves very variable in shape; it clings readily to stone or brick work by means of suckers at the ends of the branched tendrils.

AMPERE, ANDRE MARIE (1775-1836), French physicist, was born at Polemieux, near Lyons, on the 22nd of January 1775. He took a passionate delight in the pursuit of knowledge from his very infancy, and is reported to have worked out long arithmetical sums by means of pebbles and biscuit crumbs before he knew the figures. His father began to teach him Latin, but ceased on discovering the boy's greater inclination and aptitude for mathematical studies. The young Ampere, however, soon resumed his Latin lessons, to enable him to master the works of Euler and Bernouilli. In later life he was accustomed to say that he knew as much about mathematics when he was eighteen as ever he knew; but his reading embraced nearly the whole round of knowledge--history, travels, poetry, philosophy and the natural sciences. When Lyons was taken by the army of the Convention in 1793, the father of Ampere, who, holding the office of juge de paix, had stood out resolutely against the previous revolutionary excesses, was at once thrown into prison, and soon after perished on the scaffold. This event produced a profound impression on his susceptible mind, and for more than a year he remained sunk in apathy. Then his interest was aroused by some letters on botany which fell into his hands, and from botany he turned to the study of the classic poets, and to the writing of verses himself. In 1796 he met Julie Carron, and an attachment sprang up between them, the progress of which he naively recorded in a journal (Amorum). In 1799 they were married. From about 1796 Ampere gave private lessons at Lyons in mathematics, chemistry and languages; and in 1801 he removed to Bourg, as professor of physics and chemistry, leaving his ailing wife and infant son at Lyons. She died in 1804, and he never recovered from the blow. In the same year he was appointed professor of mathematics at the lycee of Lyons. His small treatise, Considerations sur la theorie mathematique du jeu, which demonstrated that the chances of play are decidedly against the habitual gambler, published in 1802, brought him under the notice of J. B. J. Delambre, whose recommendation obtained for him the Lyons appointment, and afterwards (1804) a subordinate position in the polytechnic school at Paris, where he was elected professor of mathematics in 1809. Here he continued to prosecute his scientific researches and his multifarious studies with unabated diligence. He was admitted a member of the Institute in 1814. It is on the service that he rendered to science in establishing the relations between electricity and magnetism, and in developing the science of electromagnetism, or, as be called it, electrodynamics, that Ampere's fame mainly rests. On the 11th of September 1820 he heard of H. C. Oersted's discovery that a magnetic needle is acted on by a voltaic current. On the 18th of the same month he presented a paper to the Academy, containing a far more complete exposition of that and kindred phenomena. (See ELECTROKINETICS.) The whole field thus opened up he explored with characteristic industry and care, and developed a mathematical theory which not only explained the electromagnetic phenomena already observed but also predicted many new ones. His original memoirs on this subject may be found in the Ann. Chim. Phys. between 1820 and 1828. Late in life he prepared a remarkable Essai sur la philosophie des sciences. In addition, he wrote a number of scientific memoirs and papers, including two on the integration of partial differential equations (Jour. Ecole Polytechn. x., xi.). He died at Marseilles on the 10th of June 1836. The great amiability and childlike simplicity of Ampere's character are well brought out in his Journal et correspondance (Paris, 1872).

AMPERE, JEAN JACQUES (1800-1864), French philologist and man of letters, only son of Andre Marie Ampere, was born at Lyons on the 12th of August 1800. He studied the folk-songs and popular poetry of the Scandinavian countries in an extended tour in northern Europe. Returning to France, he delivered in 1830 a series of lectures on Scandinavian and early German poetry at the Athenaeum in Marseilles. The first of these was printed as De l'Histoire de la poesie (1830), and was practically the first introduction of the French public to the Scandinavian and German epics. In Paris he taught at the Sorbonne, and became professor of the history of French literature at the College de France. A journey in northern Africa (1841) was followed by a tour in Greece and Italy, in company with Prosper Merimee and others. This bore fruit in his Voyage dantesque (printed in his Grece, Rome et Dante, 1848), which did much to popularize the study of Dante in France. In 1848 he became a member of the French Academy, and in 1851 he visited America. From this time he was occupied with his chief work, L'Histoire romaine a Rome (4 vols., 1861-1864), until his death at Pau on the 27th of March 1864.

The Correspondance et souvenirs (2 vols.) of A. M. and J. J. Ampere (1805-1854) was published in 1875. Notices of J. J. Ampere are to be found in Sainte-Beuve's Portraits litteraires, vol. iv., and Nouveaux Lundis, vol. xiii.; and in P. Merimee's Portraits historiques et litteraires (2nd ed., 1875).

AMPEREMETER, or AMMETER, an instrument for the measurement of electric currents in terms of the unit called the ampere. (See ELECTROKINETICS; CONDUCTION, ELECTRIC; and UNITS, PHYSICAL.) Since electric currents may be either continuous, i.e. unidirectional, or alternating, and the latter of high or of low frequency, amperemeters may first be divided into those (1) for continuous or direct currents, (2) for low frequency alternating currents, and (3) for high frequency alternating currents. A continuous electric current of one ampere is defined to be one which deposits electrolytically 0.001118 of a gramme of silver per second from a neutral solution of silver nitrate.1 An alternating current of one ampere is defined to be one which produces the same heat in a second in a wire as the unit continuous current defined as above to be one ampere. These definitions provide a basis on which the calibration of amperemeters can be conducted. Amperemeters may then be classified according to the physical principle on which they are constructed. An electric current in a conductor is recognized by its ability (a) to create heat in a wire through which it passes, (b) to produce a magnetic field round the conductor or wire. The heat makes itself evident by raising the temperature and therefore elongating the wire, whilst the magnetic field creates mechanical forces which act on pieces of iron or other conductors conveying electric currents when placed in proximity to the conductor in question. Hence we may classify ammeters into (1) Thermal; (2) Electromagnetic, and (3) Electrodynamic instruments.

1. Thermal Ammeters.--These instruments are also called hot-wire ammeters. In their simplest form they consist of a wire through which passes the current to be measured, some arrangement being provided for measuring the small expansion produced by the heat generated in the wire. This may consist simply in attaching one end of the wire to an index lever and the other to a fixed support, or the elongation of the wire may cause a rotation in a mirror from which a ray of light is reflected, and the movement of this ray over a scale will then provide, the necessary means of indication. It is found most convenient to make use of the sag of the wire produced when it is stretched between two fixed points (K1K2, fig. 1) and then heated. To render the elongation evident, another wire is attached to its centre S2, this last having a thread fixed to its middle of which the other end is twisted round the shaft of an index needle or in some way connected to it through a multiplying gear. The expansion of the working wire when it is heated will then increase or create a sag in it owing to its increase in

FIG. 1.--Diagram showing the arrangements of Hartmann and Braun's Hotwire Ammeter.

length, and this is multiplied and rendered evident by the movement of the index needle. In order that this may take place, the heated wire must be flexible and must therefore be a single fine wire or a bundle of fine wires. In ammeters for small currents it is customary to pass the whole current through the heating wire. In instruments for larger currents the main current passes through a metallic strip acting as a bye-pass or shunt, and to the ends of this shunt are attached the ends of the working wire. A known fraction of the current is then indicated and measured. This shunt is generally a strip of platinoid or constantin, and the working wire itself is of the same metal. There is therefore a certain ratio in which any current passing through the ammeter is divided between the shunt and the working wire.

Thermal ammeters recommend themselves for the following reasons:--(1) the same instrument can be used for continuous currents and for alternating currents of low frequency; (2) there is no temperature correction, (3) if used with alternating currents no correction is necessary for frequency, unless that frequency is very high. It is, however, requisite to make provision for the effect of changes in atmospheric temperature. This is done by mounting the working wire on a metal plate made of the same metal as the working wire itself; thus if the working wire is of platinoid it must be mounted on a platinoid bar, the supports which carry the ends of the working wire being insulated from this bar by being bushed with ivory or porcelain. Then no changes of external temperature can affect the sag of the wire, and the only thing which can alter its length relatively to the supporting bar is the passage of a current through it. Hot-wire ammeters are, however, liable to a shift of zero, and means are always provided by some adjusting screw for slightly altering the sag of the wire and so adjusting the index needle to the zero of the scale. Hot-wire ammeters are open to the following objections:--The scale divisions for equal increments of current are not equal in length, being generally much closer together in the lower parts of the scale. The reason is that the heat produced in a given time in a wire is proportional to the square of the strength of the current passing through it, and hence the rate at which the heat is produced in the wire, and therefore its temperature, increases much faster than the current itself increases. From this it follows that hot-wire ammeters are generally not capable of giving visible indications below a certain minimum current for each instrument. The instrument therefore does not begin to read from zero current, but from some higher limit which, generally speaking, is about one-tenth of the maximum, so that an ammeter reading up to 10 amperes will not give much visible indication below 1 ampere. On the other hand, hot-wire instruments are very ``dead-beat,'' that is to say, the needle does not move much for the small fluctuations in the current, and this quality is generally increased by affixing to the index needle a small copper plate which is made to move in a strong magnetic field (see fig. 2). Hot-wire instruments working on the sag principle can be used in any position if properly constructed, and are very portable. In the construction of such an instrument it is essential that the wire should be subjected to a process of preparation or ``ageing,'' which consists in passing through it a fairly strong current, at least the maximum that it will ever have to carry, and starting and stopping this current frequently. The wire ought to be so treated for many hours

FIG. 2.--Hot-wire Ammeter.

before it is placed in the instrument. It is also necessary to notice that shunt instruments cannot be used for high frequencies, as then the relative inductance of the shunt and wire becomes important and affects the ratio in which the current is divided, whereas for low frequency currents the inductance is unimportant. In constructing a hot-wire instrument for the measurement of high frequency currents it is necessary to make the working wire of a number of fine wires placed in parallel and slightly separated from one another, and to-pass the whole of the current to be measured through this strand.

In certain forms, hot-wire instruments are well adapted for the measurement of very small alternating currents. One useful form has been made as follows:--Two fine wires of diameter not greater than .001 in. are stretched parallel to one another and 2 or 3 mm. apart. At the middle of these parallel wires, which are preferably about 1 m. in length, rests a very light metallic bridge to which a mirror is attached, the mirror reflecting a ray of light from a lamp upon a screen. If a small alternating current is passed through one wire, it sags down, the mirror is tilted, and the spot of light on the screen is displaced. Changes of atmospheric temperature affect both wires equally and do not tilt the mirror. The instrument can be calibrated by a continuous current. Another form of hot-wire ammeter is a modification of the electric thermometer originally invented by Sir W. Snow Harris. It consists of a glass bulb, in which there is a loop of fine wire, and to the bulb is attached a U-tube in which there is some liquid. When a current is passed through the wire, continuous or alternating, it creates heat, which expands the air in the bulb and forces the liquid up one side of the U-tube to a certain position in which the rate of loss of heat by the air is equal to the rate at which it is gaining heat. The instrument can be calibrated by continuous currents and may then be used for high frequency alternating currents.

2. Electromagnetic Ammeters.--Another large class of ammeters depend for their action upon the fact that an electric current creates an electric field round its conductor, which varies in strength from point to point, but is otherwise proportional to the current. A small piece of iron placed in this field tends to move from weak to strong places in the field with a force depending on the strength of the field and the rate at which the field varies. In its simplest form an electromagnetic ammeter consists of a circular coil of wire in which is pivoted eccentrically an index needle carrying at its lower end a small mass of iron. The needle is balanced so that gravity compels it to take a certain position in which the fragment of iron occupies a position in the centre of the field of the coil where it is weakest. When a current is passed through the coil the iron tends to move nearer to the coil of the wire where the field is stronger and so displaces the index needle over the scale. Such an instrument is called a soft-iron gravity ammeter. Another type of similar instrument consists of a coil of wire having a fragment of iron wire suspended from one arm of an index needle near the mouth of a coil. When a current is passed through the wire forming the coil, the fragment of iron is drawn more into the aperture of the coil where the field is stronger and so displaces an index needle over a scale. In the construction of this soft-iron instrument it is essential that the fragment of iron should be as small and as well annealed as possible and not touched with tools after annealing; also it should be preferably not too elongated in shape so that it may not acquire permanent magnetization but that its magnetic condition may follow the changes of the current in the coil. If these conditions are not fulfilled sufficiently, the ammeter will not give the same indications for the same current if that current has been reached (a) by increasing from a smaller current, or (b) by decreasing from a larger current. In this case there is said to be hysteresis in the readings. Although therefore most simple and cheap to construct, such soft-iron instruments are not well adapted for accurate work. A much better form of electromagnetic ammeter can be constructed on a principle now extensively employed, which consists in pivoting in the strong field of a permanent magnet a small coil through which a part of the current to be measured is sent. Such an instrument is called a shunted movable coil ammeter, and is represented by a type of instrument shown in fig. 3. The

FIG. 3.--Shunted Movable Coil Ammeter, Isenthal & Co.

construction of this instrument is as follows:--Within the instrument is a horseshoe magnet having soft-iron pole pieces so arranged as to produce a uniform magnetic field. In this magnetic field is pivoted a small circular or rectangular coil carried in jewelled bearings, the current being passed into and out of the movable coil by fine flexible conductors. The coil carries an index needle moving over a scale, and there is generally an iron core in the interior of the coil but fixed and independent of it. The coil is so situated that, in its zero position when no current is passing through it, the plane of the coil is parallel to the direction of the lines of force of the field. When a current is passed through the coil it rotates in the field and displaces the index over the scale against the control of a spiral spring like the hairspring of a watch. Such instruments can be made to have equidivisional scales and to read from zero upwards. It is essential that the permanent magnet should be subjected to a process of ageing so that its field may not be liable to change subsequently with time.

In the case of ammeters intended for very small currents, the whole current can be sent through the coil, but for larger currents it is necessary to provide in the instrument a shunt which carries the main current, the movable coil being connected to the ends of this shunt so that it takes a definite small fraction of the current passed through the instrument. Instruments of this type with a permanent magnetic field are only available for the measurement of continuous currents, but soft-iron instruments of the above-described gravity type can be employed with certain restrictions for the measurement of alternating currents. Direct reading equidivisional movable coil ammeters can be made in various portable forms, and are very much employed as laboratory instruments and also as ammeters for the measurement of large electric currents in electric generating stations. In this last case the shunt need not be contained in the instrument itself but may be at a considerable distance, wires being brought from the shunt which carries the main current to the movable coil ammeter itself, which performs the function simply of an indicator,

3. Electrodynamic Ammeters.--Instruments of the third class depend for their action on the fact discovered by Ampere, that mechanical forces exist between conductors carrying electric currents when those conductors occupy certain relative positions. If there be two parallel wires through which currents are passing, then these wires are drawn together if the currents are in the same direction and pressed apart if they are in opposite directions. (See ELECTROKINETICS.) Instruments of this type are called Electrodynamometers, and have been employed both as laboratory research instruments and for technical purposes. In one well-known form, called a Siemens Electrodynamometer, there is a fixed coil (fig. 4), which is surrounded by another coil having its axis at right angles to that of the fixed coil. This second coil is suspended by a number of silk fibres, and to the coil is also attached a spiral spring the other end of which is fastened to a torsion head. If then the torsion head is twisted, the suspended coil experiences a torque and is displaced through

FIG. 4.--Siemens Electrodynamometer. F, Fixed coil; D, Movable coil; S, Spiral spring; T, Torsion head; MM, Mercury cups; I, Index needle.

an angle equal to that of the torsion head. The current can be passed into and out of the movable coil by permitting the ends of the coil to dip into two mercury cups. If a current is passed through the fixed coil and movable coil in series with one another, the movable coil tends to displace itself so as to bring the axes of the coils, which are normally at right angles, more into the same direction. This tendency can be resisted by giving a twist to the torsion head and so applying to the movable coil through the spring a restoring torque, which opposes the torque due to the dynamic action of the currents. If then the torsion head is provided with an index needle, and also if the movable coil is provided with an indicating point, it is possible to measure the torsional angle through which the head must be twisted to bring the movable coil back to its zero position. In these circumstances the torsional angle becomes a measure of the torque and therefore of the product of the strengths of the currents in the two coils, that is to say, of the square of the strength of the current passing through the two coils if they are joined up in series. The instrument can therefore be graduated by passing through it known and measured continuous currents, and it then becomes available for use with either continuous or alternating currents. The instrument can be provided with a curve or table showing the current corresponding to each angular displacement of the torsion head. It has the disadvantage of not being direct reading when made in the usual form, but can easily be converted into a direct reading instrument by appropriately dividing the scale over which the index of the torsion head moves.

Ampere Balance.--Very convenient and accurate instruments based on the above principles have been devised by Lord Kelvin, and a large variety of these ampere balances, as they are called, suitable for measuring currents from a fraction of an ampere up to many thousands of amperes, have been constructed by that illustrious inventor. The difficulty which has generally presented itself to those who have tried to design instruments on the

FIG. 5.--Kelvin Flexible Metallic Ligament.

electrodynometer principle for use with large currents has been that of getting the current into and out of the movable conductor, and yet permitting that conductor to remain free to move under very small force. The use of mercury cups is open to many objections on account of the fact that the mercury becomes oxidized, and such instruments are not very convenient for transportation. The great novelty in the ampere balances of Lord Kelvin was a joint or electric coupling, which is at once exceedingly flexible and yet capable of being constructed to carry with safety any desired current. This he achieved by the introduction of a device which is called a metallic ligament. The general principle of its construction is as follows:--Let +A, -A (fig. 5), be a pair of semi-cylindrical fixed trunnions which are carried on a supporting frame and held with flat sides downwards. Let +B, -B, be two smaller trunnions which project out from the sides of the two strips connecting together a pair of rings CC. The rings and the connecting strips constitute the circuit which is to be rendered movable. A current entering by the trunnion + B flows round the two halves of the circuit, as shown by the arrows, and comes out at the trunnion -B. In fig. 5 the current is shown dividing round the two rings; but in all the balances, except those intended for the largest currents, the current really circulates first round one ring and then round the other. To make the ligament, a very large number of exceedingly fine copper wires laid close together are soldered to the upper surface of the upper trunnion. The movable circuit CC thus hangs by two ligaments which are formed of very fine copper wires. This mode of suspension enables the conductor CC to vibrate freely like a balance, but at the same time very large currents can easily be passed through this perfectly flexible joint. Above and below these movable coils, which form as it were the two scale- pans of a balance, are fixed other stationary coils, and the connexions of all these six coils (shown in fig. 6) are such that when a current

FIG. 6.--Connexions of Kelvin Ampere Balance.

is passed through the whole of the coils in series, forces of attraction and repulsion are brought into existence which tend to force one movable coil upwards and the other movable coil downwards. This tendency is resisted by the weight of a mass of metal, which can be caused to slide along a tray attached to the movable coils. The appearance of the complete instrument is shown by fig. 7. When a current is passed through the instrument it causes one end of the movable system to tilt downwards, and the other end upwards; the sliding weight is then moved along the tray by means of a silk cord until equilibrium is again established. The value of the current in amperes is then obtained approximately by observing the position of the weight on the scale, or it may be obtained more accurately in the following

FIG. 7.--Lord Kelvin's Ampere Balance.

manner:--The upper edge of the shelf on which the weights slide (see fig. 8) is graduated into equal divisions, and the weight is provided with a sharp tongue of metal in order that its position on the shelf may be accurately determined. Since the current passing through the balance when equilibrium is obtained with a given weight is proportional to the square root of the couple due to this weight, it follows that the current strength when equilibrium is obtained is proportional to the product of the square root of the weight used

FIG. 8.--Slider of Kelvin Ampere Balance.

and the square root of the displacement distance of this weight from its zero position. Each instrument is accompanied by a pair of weights and by a square root table, so that the product of the square root of the number corresponding to the position of the sliding weight and the ascertained constant for each weight, gives at once the value of the current in amperes. Each of these balances is made to cover a certain range of reading. Thus the centi-ampere balance ranges from 1 to 100 centi-amperes, the deci-ampere balance from 1 to 100 deci-amperes, the ampere balance from 1 to 100 amperes, the deka-ampere balance from 1 to 100 amperes, the hecto-ampere balance from 6 to 600 amperes, and the kilo-ampere balance from 100 to 2500 amperes. They are constructed for the measurement not only of continuous or unvarying but also of alternating currents. In those intended for alternating currents, the main current through the movable coil, whether consisting of one turn or more than one turn, is carried by a wire rope, of which each component strand is insulated by silk covering, to prevent the inductive action from altering the distribution of the current across the transverse section of the conductor. To avoid the creation of induced currents, the coil frames and the base boards are constructed of slate. Kelvin ampere balances are made in two types--(1) a variable weight type suitable for obtaining the ampere value of any current within their range; and (2) a fixed weight type intended to indicate when a current which can be varied at pleasure has a certain fixed value. An instrument of the latter type of considerable accuracy was designed by Lord Kelvin for the British Board of Trade Electrical Laboratory, and it is there used as the principal standard ampere balance. A fixed weight is placed on one coil and the current is varied gradually until the balance is just in equilibrium. In these circumstances the current is known to have a fixed value in amperes determined by the weight attached to the instrument.

Calibration.--The calibration of ammeters is best conducted by means of a series of standard low resistances and of a potentiometer (q.v..) The ammeter to be calibrated is placed in series with a suitable low resistance which may be .1 ohm, .01 ohm, .001 ohm or more as the case may be. A steady continuous current is then passed through the ammeter and low resistance, placed in series with one another and adjusted so as to give any required scale reading on the ammeter. The potential difference of the ends of the low resistance is at the same time measured on the potentiometer, and the quotient of this potential difference by the known value of the low resistance gives the true value of the current passing through the ammeter. This can be then compared with the observed scale reading and the error of the ammeter noted.2

A good ammeter should comply with the following qualifications:--(1) its readings should be the same for the same current whether reached by increasing from a lower current or decreasing from a higher current; (2) if used for alternating currents its indications should not vary with the frequency within the range of frequency for which it is likely to be used; (3) it should not be disturbed by external magnetic fields; (4) the scale divisions should, if possible, be equal in length and there should be no dead part in the scale. In the use of ammeters in which the control is the gravity of a weight, such as the Kelvin ampere balances and other instruments, it should be noted that the scale reading or indication of the instrument will vary with the latitude and with the height of the instrument above the mean sea-level. Since the difference between the acceleration of gravity at the pole and at the equator is about 1/2%, the correction for latitude will be quite sensible in an instrument which might be used at various times in high and low latitudes. If G is the acceleration of gravity at the equator and g that at any latitude l, then g = G (1 + 0.00513 sin2 l). In the case of an instrument with gravity control, the latitude at which it is calibrated should therefore be stated.

FIG. 9.-- Edgewise Switchboard Ammeter, Kelvin & James White Ltd.

Switchboard Ammeters.--For switchboard use in electric supply stations where space is valuable, instruments of the type called edgewise ammeters are much employed. In these the indicating needle moves over a graduated cylindrically shaped scale, and they are for the most part electromagnetic instruments (see fig. 9).

BIBLIOGRAPHY.--Lord Kelvin (Sir W. Thomson), ``New Standard and Inspectional Electrical Measuring Instruments,'' Proc. Soc. Telegraph Engineers, 1888, 17, p. 540; J. A. Fleming, A Handbook for the Electrical Laboratory and Testing Room (2 vols., London, 1901, 1903 ); G. D. Aspinall Parr, Electrical Measuring Instruments (Glasgow, 1903); J. Swinburne, ``Electric Light Measuring instruments,'' Proc. Inst. Civ. Eng., 1891-1892, 110, pt. 4; K. Edgcumbe and F. Punga, ``Direct Reading Measuring Instruments for Switchboard Use,'' Jour. Inst. Elec. Eng., 1904, 33, p. 620. (J. A. F.)

1 See J. A. Fleming, A Handbook for the Electrical Laboratory and Testing Room, vol. i. p. 341 (1901), also A. Gray, Absolute Measurements in Electricity and Magnetism, vol. ii. pt. ii. p. 412 (1893).

2 See ``The Electrolysis of Copper Sulphate in Standardizing Electrical Instruments,'' by A. W. Meikle, read before the Physical Society of Glasgow University on the 27th of January 1888, or J. A. Fleming, A Handbook for the Electrical Laboratory and Testing Room, vol. i. p. 343.

AMPERSAND (a corruption of the mixed English and Latin phrase, ``and per se and,'' of which there are many dialect forms, as ``ampussyand,'' or ``amperseand''), the name of the sign & or &, which is a combination of the letters e, t, of the Lat. et= and. The sign is now usually called ``short and.'' In old-fashioned primers and nursery books the name and sign were always added at the end of the alphabet.

AMPHIARAUS, in Greek mythology, a celebrated seer and prince of Argos, son of Oicles (or Apollo) and Hypermestra, and through his father descended from the prophet Melampus (Odyssey, xv. 244). He took part in the voyage of the Argonauts and in the chase of the Calydonian boar; but his chief fame is in connexion with the expedition of the Seven against Thebes, organized by Adrastus, the brother of his wife Eriphyle, for the purpose of restoring Polyneices to the throne. Amphiaraus, foreseeing the disastrous issue of the war, at first refused to share in it; he had, however, promised Eriphyle when he married her that, in the event of any dispute arising between her brother and himself, she should decide between them; and now Eriphyle, bribed by Polyneices with the fatal necklace given by Cadmus to Harmonia, persuaded him against his better judgment to set out on the expedition. Knowing his doom, he bade his sons, Alcmaeon and Amphilochus, avenge his death upon their mother, upon whom, as he stepped into his chariot, he turned a look of anger. This scene was represented upon the chest of Cypselus described by Pausanias (v. 17).

The assault on Thebes was disastrous for the Seven; and Amphiaraus, pursued by Periclymenus, would have been slain with his spear, had not Zeus with a thunderbolt opened a chasm into which the seer, with his chariot, horses and charioteer, disappeared. Henceforth he was numbered with the immortals and worshipped as a god. Near Oropus, on the supposed site of his passing, his sanctuary arose, with healing springs, and an oracle famous for its interpretation of dreams (Pausanias i. 34). The ruins of this temple, with inscriptions which identify it, have been discovered and preserved at Mavrodilisi, in the provinces of Boeotia and Attica. There was another temple dedicated to him on the road from Thebes to Potniae, and here was the oracle of Amphiaraus consulted by Croesus and Mardonius.

Homer, Odyssey, xi. 326; Herodotus viii. 134; Pindar, Olympia, vi., Nemea, ix.; Apollodorus iii. 6.

AMPHIBIA, a zoological term originally employed by Linnaeus to denote a class of the Animal Kingdom comprising crocodiles, lizards and salamanders, snakes and Caeciliae, tortoises and turtles and frogs; to which, in the later editions of the Systema Naturae he added some groups of fishes. In the Tableau Elementaire, published in 1795, Cuvier adopts Linnaeus's term in its earlier sense, but uses the French word ``Reptiles,'' already brought into use by Brisson, as the equivalent of Amphibia. In addition Cuvier accepts the Linnaean subdivisions of Amphibia-Reptilia for the tortoises, lizards (including crocodiles), salamanders and frogs; and Amphibia-Serpentes for the snakes, apodal lizards and Caeciliae.

In 17991 Alexandre Brongniart pointed out the wide differences which separate the frogs and salamanders (which he terms Batrachia) from the other reptiles; and in 1804 P. A. Latreille,2 rightly estimating the value of these differences, though he was not an original worker in the field of vertebrate zoology, proposed to separate Brongniart's Batrachia from the class of Reptilia proper, as a group of equal value, for which he retained the Linnaean name of Amphibia.

Cuvier went no further than Brongniart, and, in the Regne Animal, he dropped the term Amphibia, and substituted Reptilia for it. J. F. Meckel,3 on the other hand, while equally accepting Brongniart's classification, retained the term Amphibia in its earlier Linnaean sense; and his example has been generally followed by German writers, as, for instance, by H. Stannius, in that remarkable monument of accurate and extensive research, the Handbuch der Zootomie (2nd ed., 1856).

In 1816, de Blainville,4 adopting Latreille's view, divided the Linnaean Amphibia into Squamiferes and Nudipelliferes, or Amphibiens; though he offered an alternative arrangement, in which the class Reptiles is preserved and divided into two subclasses, the Ornithoides and the Ichthyoides. The latter are Brongniart's Batrachia, plus the Caeciliae, whose true affinities had, in the meanwhile, been shown by A. M. C. Dumeril; and, in this arrangement, the name Amphibiens is restricted to Proteus and Siren.

B. Merrem's Pholidota and Batrachia (1820), F. S. Leuckart's Monopnoa and Dipnoa (1821), J. Muller's Squamata and Nuda (1832), are merely new names for de Blainville's Ornithoides and Ichthyoides, though Muller gave far better anatomical characters of the two groups than had previously been put forward.

Moreover, following the indications already given by K. E. von Baer in 1828,5 Muller calls the attention of naturalists to the important fact, that while all the Squamata possess an amnion and an allantois, these structures are absent in the embryos of all the Nuda. An appeal made by Muller for observations on the development of the Caeciliae, and of those Amphibia which retain gills or gill-clefts throughout life, has unfortunately yielded no fruits.

In 1825 P. A. Latreille6 published a new classification of the Vertebrata, which are primarily divided into Haematherma. containing the three classes of Mammifera, Monotremata and Aves; and Haemacryma, also containing three classes-- Reptilia, Amphibia and Pisces. This division of the Vertebrata into hot and cold blooded is a curiously retrograde step, only intelligible when we reflect that the excellent entomologist had no real comprehension of vertebrate morphology; but he makes some atonement for the blunder by steadily upholding the class distinctness of the Amphibia. In this he was followed by Dr J. E. Gray; but Dumeril and Bibron in their great work,7 and Dr Gunther in his Catalogue, in substance, adopted Brongniart's arrangement, the Batrachia being simply one of the four orders of the class Reptilia. Huxley adopted Latreille's view of the distinctness of the Amphibia, as a class of the Vertebrata, co-ordinate with the Mammalia, Aves, Reptilia and Pisces; and the same arrangement was accepted by Gegenbaur and Haeckel. In the Hunterian lectures delivered at the Royal College of Surgeons in 1863, Huxley divided the Vertebrata into Mammals, Sauroids and Ichthyoids, the latter division containing the Amphibia and Pisces. Subsequently he proposed the names of Sauropsida and Ichthyopsida for the Sauroids and Ichthyoids respectively.

Sir Richard Owen, in his work on The Anatomy of Vertebrates, followed Latreille in dividing the Vertebrata into Haematotherma and Haematocrya, and adopted Leuckart's term of Dipnoa for the Amphibia. T. H. Huxley, in the ninth edition of this Encyclopaedia, treated of Brongniart's Batrachia, under the designation Amphibia, but this use of the word has not been generally accepted. (See BATRACHIA.) (T. H. H.; P. C. M.)

1 Brongniart's Essai d'une classification naturelle des reptiles was not published in full till 1803. It appears in the volume of the Memoires presentes a l'Institut par divers savans for 1805.

2 Nouveau dictionnaire d'histoire naturelle, xxiv., cited in Latreille's Fannilles naturelles du regne animal.''

3 System der vergleichenden Anatomie (1821).

4 ``Prodrome d'une Nouvelle Distribution du regne Animal.'' Bulletin des sciences par la Societe Philomatique de Paris (1816), p. 113.

5 Entwickelungs-Geschichte der Thiere, p. 262

6 Familles naturelles du regne animal.

7 Erpetologie generale, ou histoire naturelle complete des reptiles (1836).

AMPHIBOLE, an important group of rock-forming minerals, very similar in chemical composition and general characters to the pyroxenes, and like them falling into three series according to the system of crystallization. They differ from the pyroxenes, however, in having an angle between the prismatic cleavage of 56 deg. instead of 87 deg. ; they are specifically lighter than the corresponding pyroxenes; and, in their optical characters, they are distinguished by their stronger pleochroism and by the wider angle of extinction on the plane of symmetry.

They are minerals of either original or secondary origin; in the former case occurring as constituents (hornblende) of igneous rocks, such as granite, diorite, andesite, &c. Those of secondary origin have either been developed (tremolite) in limestones by contact-metamorphism, or have resulted (actinolite) by the alteration of augite by dynamo-metamorphism. Pseudomorphs of amphibole after pyroxene are known as uralite.

The name amphibole (from the Gr. amfibolos, ambiguous) was used by R. J. Hauy to include tremolite, actinolite and hornblende; this term has since been applied to the whole group. Numerous sub-species and varieties are distinguished, the more important of which are tabulated below in three series. The formulae of each will be seen to conform to the general metasilicate formula R''SiO3.

ORTHORHOMBIC SERIES. Anthophyllite . . (Mg,Fe)SiO3. MONOCLINIC SERIES. Tremolite . . CaMg3(SiO3)4. Actinolire . . Ca(Mg,Fe)3(SiO3)4. Cummingtonite . (Fe,Mg)SiO3. Richterite . . (K2,Na2,Mg,Ca,Mn)SiO3. Hornblende . . {Ca(Mg,Fe)3(SiO3)4 with {NaAl(SiO3)2 and (Mg,Fe) (Al,Fe)2SiO6. MONOCLINIC SERIES--continued.

Glaucophane . . NaAl(SiO3)2.(Fe,Mg)SiO3. Crocidolite . . NaFe(SiO3)2.FeSiO3. Riebeckite . . 2NaFe(SiO3)2.FeSiO3. Arfvedsonite . . Na8(Ca,Mg)3(Fe,Mn)14(Al,Fe)2 Si21O45. ANORTHIC SERIES. Aenigmatite . . Na4Fe''9Al Fe'' '(Si,Ti)12O38.

Of these, tremolite, hornblende and crocidolite, as well as the important varieties, asbestos and jade, are treated under their own headings. Brief mention only need be here made of some of the others. Naturally, on account of the wide variations in chemical composition, the different members vary considerably in characters and general appearance; the specific gravity, for example, varies from 2.9 in tremolite to 3.8 in aenigmatite.

Anthophyllite occurs as brownish, fibrous or lamellar masses with hornblende in mica-schist at Kongsberg in Norway and some other localities. An aluminous variety is known as gedrite, and a deep green, Russian variety containing little iron as kupfferite.

Actinolite is an important member of the monoclinic series, forming radiating groups of acicular crystals of a bright green or greyish-green colour. It occurs frequently as a constituent of crystalline schists. The name (from aktis, a ray, and lithos, a stone) is a translation of the old German word Strahlstein, radiated stone.

Glaucophane, crocidolite, riebeckite and arfvedsonite form a somewhat special group of alkali-amphiboles. The two former are blue fibrous minerals occurring in crystalline schists, and are the result of dynamo-metamorphic processes; the two latter are dark green minerals which occur as original constituents of igneous rocks rich in soda, such as nepheline-syenite and phonolite.

Aenigmatite and its variety cossyrite are rare minerals forming constituents of igneous rocks of the nepheline-syenite and phonolite groups. (L. J. S.)

AMPHIBOLITE, the name given to a rock consisting mainly of amphibole (hornblende), the use of the term being restricted, however, to metamorphic rocks. Holocrystalline plutonic igneous rocks composed essentially of hornblende are known as hornblendites. As is the case with most petrological terms the exact connotation is not very strictly defined; most authors allow that accessory minerals such as felspar, garnet, augite and quartz may be present in variable and often considerable amount. A foliated or schistose structure, though often developed in these rocks, is not universal. The hornblende is usually dark green (actinolite) but may be nearly black in the hand specimen; in the microscopic slide it is commonly green of various shades, but may be brown, blue or nearly colourless. It frequently occurs in elongated bladed prisms, but rarely shows good crystal faces. The term hornblende-schist is employed by many writers as nearly synonymous with amphibolite; most hornblende-schists contain felspar and iron oxides, while sphene, rutile, quartz and apatite are rarely absent. Reddish garnets are often conspicuous in the rocks of this group (garnet-amphibolites), and when in addition a green-coloured augite occurs the rocks are intimately allied to the hornblende-eclogites. Epidote also, in yellow grains, is common (epidote-amphibolites), and in these rocks the hornblende may be of the blue and richly pleochroic variety known as glaucophane (glaucophane-epidote-schists). Hornblende-schists containing dark green ferriferous hornblende (grunorite-schists) are abundant in some parts of North America. Tremolite-schists consist essentially of white or very pale green amphibole; occasionally they are black from the presence of numerous minute grains of iron oxide or of graphite. Many tremolite-schists contain much talc and chlorite, and as these rocks have been derived from peridotites they not infrequently show residual grains of olivine. Nephrite (Gr. nefros, a kidney) is a very compact, hardly schistose amphibolite, consisting of fine interwoven fibres of hornblende. Among other accessory minerals biotite, chlorite, talc, scapolite and tourmaline may be mentioned; if abundant they give rise to special varieties such as biotite-amphibolite, &c.

The amphibolites are typical rocks of the metamorphic group and as such attain a large development in all regions of crystalline schists and gneisses such as the Alps, Ardennes, Harz, Scottish Highlands, and the Lakes district of North America. They occur in two ways, viz. as large circular or elliptical areas which mark the site of old plutonic stocks or bosses of basic rock, and as long narrow strips intercalated among outcrops of other metamorphic rocks. Regarded from the point of view of their origin they fall into two groups, the ortho-amphibolites, which are modified igneous rocks, and the para-amphibolites, which are altered sediments. The former are far the more common. Igneous rocks which contain much augite (e.g. dolerites, gabbros, diabases, pyroxenites and many peridotites) are usually converted into amphibolites when they are subjected to pressure and interstitial movements during earth-folding. If felspar be present also, epidote may form, while part of the felspar recrystallizes as a species of the same mineral richer in alkalies or as mica. Olivine and ilmenite, the other common constituents of these rocks, may, alone or in conjunction with the above-named minerals, yield garnet, talc, sphene, rutile, &c. There is little or no alteration in the bulk composition of the rock, but its component elements enter into new combinations. Chemical analysis, accordingly, will often enable us to identify an igneous rock (diabase, &c.) under the guise of an amphibolite. The transformation of the rock may be complete, so that no trace is left of the original structures or minerals. Very often, however, it is only partial, and by obtaining a sufficiently large number of specimens a series of intermediate or transitional stages may be studied; these prove conclusively the nature of the process, though its causes are less clearly understood. Green hornblende may be seen gradually replacing augite, at first in needle-like crystals, for which gradually more compact masses are substituted. The felspar breaks up into a mosaic in which albite, epidote or zoisite, quartz and garnet may often be identified. Biotite and primary hornblende suffer comparatively little change; olivine disappears, and garnet, talc and tremolite or anthophyllite take its place. The original structures of this group of rocks (ophitic, porphyritic, poikilitic, vesicular, &c.) gradually fade away, and merge into those of the metamorphic amphibolites. Even when the greater part of the rock mass has suffered complete reconstruction, kernels or phacoids may remain, showing the old igneous structures, though the minerals are greatly altered. The transitional stages from gabbro or diabase to amphibolite are so common that they form a widespread and important group of rocks, which have been described under the names greenstone, greenstone-schist, flaser-gabbro, saussurite- gabbro, meta-diabase, &c. The ortho-amphibolites also include a small group of igneous rocks, which have a foliated or banded structure due to movements and pressure during consolidation, e.g. foliated diorite or diorite-schist.

The sedimentary amphibolites or para-amphibolites, less common than those above described, are frequent in some districts, such as the northern Alps, southern highlands of Scotland, Green Mountains, U.S.A. Many of them have been ash-beds, and their conversion into hornblende-schists follows exactly similar stages to those exemplified by basic crystalline igneous rocks. Others have been greywackes of varied composition with epidote, chlorite, felspar, quartz, iron oxides, &c., and may have been mixed with volcanic materials, or may be partly derived from the disintegration of basic rocks. When they are most metamorphosed they are often very hard to distinguish from igneous hornblende-schists; yet they rarely fail to reveal signs of bedding, pebbly structure, sedimentary banding and gradual transition into undoubtedly sedimentary types of gneiss and schist. Deposits containing dolomite and siderite also readily yield amphibolites (tremolite-schists, grunorite-schists, &c.) especially where there has been a certain amount of contact metamorphism by adjacent granitic masses. (J. S. F.)

AMPHIBOLOGY, or AMPHIBOLY (Gr. ampibolia), in logic, a verbal fallacy arising from ambiguity in the grammatical structure of a sentence (Aristot., Organon,Soph., El., chap. iv.). It occurs frequently in poetry, owing to the alteration for metrical reasons of the natural order of words; Jevons quotes as an example Shakespeare, Henry VI.: ``The duke yet lives that Henry shall depose.''

AMPHICTYONY (Gr. amfiktuonia, i.e. a body composed of amfiktiones, amfiktuones, ``dwellers around''), an association of ancient Greek communities centring in a shrine. As the extant sources do not define the term, and as they apply it to but five or six associations, the majority of which are little known, modern scholars are in doubt as to the essential character of the institution, and hesitate therefore to extend the name beyond this limited list. The word itself indicates that the association primarily comprised neighbours, though the Delphic amphictyony came in time to include relatively distant communities (Strabo ix. 3, 7). For the origin of the institution it is safe to assume that neighbouring communities, whether tribes (ethne) or cities, desiring friendly intercourse with one another chose the sanctuary of some deity conveniently situated, at which to hold their periodical festival for worship and their fair for the interchange of goods. If the limited use of the word according to our sources is not purely accidental, at all events there were many Greek leagues, not expressly termed amphictyonies, which had the characteristics here stated.

The Delian amphictyony probably reached the height of its splendour early in the 7th century B.C. The Hymn to the Delian Apollo, composed about that time, celebrates the gathering of the Ionians with their wives and children at the shrine of their god on the island of Delos, to worship him with music, dancing and gymnastic contests (vv. 146-164; cf. Thuc. iii. 104). The later misfortunes of the Ionians caused a decline of the festival. Peisistratus, taking possession of Delos, seems to have used the sanctuary as a means of extending his political influence. When after the great war with Persia the Aegean cities under the leadership of Athens united in a political league (477 B.C.), they chose as its centre the temple of the Delian Apollo, doubtless through a desire to connect the new alliance with the associations of the old amphictyony. How far the council and other institutions of the Delian confederacy were based upon the amphictyonic organization cannot be determined. The removal of the treasury to Athens in 454 B.C. deprived Delos of political importance, though the amphictyony continued. The council gradually dwindled, and probably came to an end without formal abolition. In 426 B.C. the Athenians purified the island and instituted a great festival to be held under their presidency every four years (Thuc. iii. 104). In 422 they expelled the Delians (Thuc. v. 1). At the end of the Peloponnesian War Athens was deprived of Delos along with her other possessions, but she appears to have regained control of the island after the victory of Cnidus (394). An inscription of 390 B.C. proves that at this date Athenian authority had been restored. The affairs of the temple were managed by a board of five Athenian amphictyons, assisted by some Delian officials (inscrr. in Bull. Hell. viii. 284, 304, 307 f.); and in the 4th century we again hear of a council in addition to the board (CIG. i. 158). At this time the amphictyony is known to have embraced both the Athenians and the inhabitants of the Cyclades; but a strong Delian party bitterly opposed Athenian rule (cf. inscr. in Bull. Hell. iii. 473 f.), which came to an end with the supremacy of Macedon. The dissolution of the amphictyony soon followed.

Far more famous is the Delphic, or more strictly, the Pylaeic-Delphic, amphictyony. It was originally composed of twelve tribes dwelling round Thermopylae--the Thessalians, Boeotians, Dorians, Ionians, Perrhaebians, Magnetes, Locrians, Oetaeans, Phthiotes, Mahans, Phocians (Aeschin. ii. 116), and Dolopians (Paus. x. 8. 2). The name of the council (pylaea) and of one set of deputies (pylagori), together with the important place held in the amphictyony by the temple of Demeter at Anthela, near Thermopylae, suggests that this shrine was the original centre of the association. How and when Delphi became a second centre is quite uncertain. The council of the league included deputies of two different kinds--pylagori and hieromnemones. the latter were twenty-four in number, two from each tribe. As the league was originally made up of neighbours, the Dorian tribe must have comprised simply the inhabitants of Doris; the Locrians were probably the eastern (Opuntian) branch; and the Ionians were doubtless limited to the adjacent island of Euboea. Afterwards, by affiliating themselves to Doris, the Peloponnesian Dorians gained admission, and Athens must have entered as an Ionian city before the first Sacred War. Henceforth Athens monopolized one of the two Ionian votes, while the other passed in rotation among the remaining Ionic, perhaps only among the Euboeic, cities. In the same way Doris held one Dorian vote and the other passed in rotation among the Dorian cities of Peloponnesus; and the east and west Locrians came to have one each. When after the second Sacred War the Phocians were expelled, Macedon received their two votes (346 B.C.) About the same time the Perrhaebians and the Dolopians were deprived of half their representation, and the two votes were transferred to the Delphians (inscrr. in N. Jahrb. f. cl. Philol. clv. 742, cf. 743, 753; Bull. Hell. xxi. 322, cf. 325; Bourguet, Sanct. Pyth. 145, 147). In the following century the Aetolians gained such dominance in the amphictyony as to convert the council into an organ of their league. Recent research has made it appear certain (cf. Pomptow, ib. 754 ff.) that they were never formally admitted to membership, but that they maintained their supremacy in the council (Livy xxxi. 32. 3; Polyb. iv. 25. 8) by controlling the votes of their allies, who-- called Aetolians in the inscriptions--were often in the majority. They made no material change in its composition, which, accordingly, after the dissolution of their league by the Romans is found to be nearly as it was after the second Sacred War. A few minor changes came in under the supremacy of the Roman republic; and finally Augustus increased the number of votes to thirty, and distributed them according to his pleasure. In the age of the Antonines the association was still in existence (paus. x. 8. 4 f.).

Although the hieromnemones of the Thessalians, who held the presidency, and perhaps of a few other communities, must have been elected, the office was ordinarily, as at Athens, filled by lot. As a rule they were renewed annually (Aristoph. Clouds, 623 f.; Foucart, in Bull. Hell. vii. 411, 413 f.). Each hieromnemon was accompanied by two pylagori, elected semi-annually (Demosth. xviii. 149; Aeschin. iii. 115; Tim. Lex. Plat., s.v. 'Amfiktuones), and representing the same tribe, though not necessarily the same city. On one occasion Athens is known to have sent three. The hieromnemones were formally superior, but because of the method of appointment they were necessarily men of mediocre ability, inexperienced in speaking and public business, and for that reason they readily became the tools of the pylagori, who were orators and statesmen. In the literary sources, accordingly, the latter are rightly given credit for the acts of the council; it was the pylagori who set a price on the head of the traitor Ephialtes ( Herod. vii. 213 ), and who on the motion of Themistocles rejected the proposition of Lacedaemon for the expulsion of the states which had sided with Persia (Plut. Them. 20). The pylagori had a right to propose measures and to take part in the deliberations; they as well as the hieromnemones were required to take the juror's oath; and the acts of the council were inscribed officially as resolutions of the hieromnemones and pylagori conjointly. The hieromnemon, however, cast the vote of his community, though in the record his two pylagori were made equally responsible for it. The necessary inference from these facts is that the vote was determined by a majority of the three deputies (inscr. in Bull. Hell. xxvii. 106-111, A 20-33; B 1-10). The council decided all questions which fell within its competence. Matters of greater importance, as the levy of an extraordinary fine on a state or the declaration of a sacred war, it presented in the form of a resolution to an assembly (ekklesia), composed of the deputies, the amphictyonic priests, and any other citizens of the league who chanced to be present (Aeschin. iii. 124; cf. Hyp. iv. 7, 26 f.). This assembly was relatively unimportant, however, and is mentioned only by the two authorities here cited.

It is now well established by epigraphic evidence (Bull. Hell. vii. 412 f., 417; Pomptow, in N. Jahrb. f. cl. Philol. cxlix. 826-829) that the amphictyons met both in the spring and in the autumn at Delphi, and the literary sources should alone be sufficient authority for meetings in the same seasons at Thermopylae (Hyp. iv. 7, 25 ff.; Strabo ix. 3, 7, 4, 17; Harpocration, s.v. Pulai.) It is known, too, that the meeting at Thermopylae followed that at Delphi (inscr. in Bull. Hell. xxiv. 136 f.).

The primary function of the council was to administer the temporal affairs of the two shrines, of which the sanctuary of Apollo at Delphi claimed by far the greater share of attention. The hieromnemones were required periodically to inspect the lands belonging to this god, to punish those who encroached, and to see that the tenants rendered their quota of produce; and the council held the states responsible for the right performance of such duties by their respective deputies (CIA. ii. 545; inscr. in Bull. Hell. vii. 428 f.). Another task of the council was to supervise the treasury, to protect it from thieves, and by investments to increase the capital (Strabo ix. 3, 7; Isoc. xv. 232; Demosth. xxi. 144; Plut. Sull. 12). Naturally, too, it controlled the expenditure. We find it, accordingly, in the 6th century B.C. contracting for the rebuilding of the Delphic temple after it had been destroyed by fire (Herod. v. 62; Paus. x. 5. 13), and in the 4th century creating an Hellenic college of temple-builders for the purpose (inscrr. in Bull. Hell. xx. 202 f., 206, xxi. 478, xxiv. 464), adorning the interior with statues and pictures (Diod. xvi. 33), inscribing the proverbs of the Seven Sages on the walls (Paus. x. 24. 1), bestowing crowns on benefactors of the god (CIG. i. 1689 b), preparing for the Pythian games, awarding the prizes (Pind. Pyth. iv. 66, x. 8 f.), instituting a board of treasurers (inscr. in Bourguet, Sanct. Pyth. 175 ff.) and issuing coins. It was also in the material interest of Apollo that the council passed a law which forbade the Greeks to levy tolls on pilgrims to the shrine (Aeschin. iii. 107; Strabo ix. 3, 4), and another requiring the amphictyonic states to keep in repair their own roads which led towards Delphi (CIA. ii. 545). A law of great interest, dating from the beginning of the institution, imposed an oath upon the members of the league not to destroy an amphictyonic city or to cut it off from running water in war or peace; but to wage war upon those who transgressed this ordinance, to destroy their cities, and to punish any others who by theft or plotting sought to injure the god (Aeschin. ii. 115). In this regulation, which was intended to mitigate the usages of war amongst the members of the league, we have one of the origins of Greek interstate law. Though other regulations were made to secure peace at the time of the festival (Dion. Hal. iv. 25. 3), and though occasionally the council was called upon to arbitrate in a dispute (cf. Demosth. xviii. 135), no provision was made to compel arbitration.

For the enforcement of such laws and for administrative efficiency in general it was necessary that the council should have judicial power. As jurors the deputies took an oath to decide according to written law, or in cases not covered by law, according to their best will and judgment (CIA. ii. 545). The earliest known amphictyonic penalty was the destruction of Crisa for having levied tolls on pilgrims (Aeschin. iii. 107; Strabo ix. 3, 4; cf. Paus. x. 37. 5-8). This offence was the cause of the first Sacred War. The second and third Sacred Wars, fought in the 4th century B.C., were waged by the amphictyons against the Phocians and the Amphissaeans respectively for alleged trespassing on the sacred lands (Aeschin. iii. 124, 128; Diod. xvi. 23, 31 f.). In the 5th century the council fined the Dolopians for having disturbed commerce by their piracy (Plut. Cim. 8), and in the 4th century the Lacedaemonians for having occupied the citadel of Thebes in time of peace (Diod. xvi. 23, 29).

The judgments of the council were sometimes considered unfair, and were occasionally defied by the states affected. The Lacedaemonians refused to pay the fine above mentioned; the Athenians protested against the treatment of Amphissa, and were slow in accepting the decisions given under the influence of Macedon. The inability of the council to enforce its resolutions was chiefly due to its composition; the majority of the communities represented were even in combination no match for individual cities like Athens, Sparta or Thebes. The council was a power in politics only when manipulated by a great state, as Thebes, Macedon or Aetolia, and in such a case its decrees were most likely to give offence by their partisanship. Although the council sometimes championed the Hellenic cause, as could any association or individual, it never acquired a recognized authority over all Greece; and notwithstanding its frequent participation in political affairs, it remained essentially a religious convocation.

In addition to the three associations thus far mentioned there was an amphictyony of Onchestus (Strabo ix. 2, 33). It may be inferred from a comparison of Paus. iv. 5. 2 with Herod. vi. 92 that there was an amphictyony of Argos of which Epidaurus and Aegina were members. An amphictyony of Corinth has, with less justification, been assumed on the strength of a passage in Pindar (Nem. Od. vi. 40-42).

AUTHORITIES.--Foucart, ``Amphictyones,'' in Daremberg and Saglio, Dict. d. antiq. grecq. et rom. (1873) i. 235-238; F. Qauer, ``Amphiktyonia,'' in Pauly-Wissowa, Realencycl. d. cl. Altertumswiss. (1894) i. 1904-1935; Pomptow, Fasti Delphici, ii. in Neue Jalhrb. f. cl. Philol. (1894) cxlix. 497-558, clv. (1897) 737-763, 783-848; E. A. Freeman, History of Federal Government in Greece and Italy (2nd ed., London and New York, 1895), 95-111; W. S. Ferguson, Schomann-Lipsius, Griechische Alterthumer (1902), ii. 29-44; E. Bourguet, L'Administration financiere du sanctuaire pythioue au IVe siecle avant J.-C (Paris, 1905). The earlier literature has been deprived of a great part of its value by recent discoveries of inscriptions, many of which may be found in the Bulletin de correspondance hellenique, iii. vii. viii. x. xx. xxi. xxiv. xxvi. xxvii., edited with commentary chiefly by Bourguet, Colin, Foucart and Homolle. See also H. Collitz, Sammlung d. griech. Dialekt-Inschriften, ii. p. 643 ff. and Nos. 2508 ff., edited by Baunack. (G. W. B.)

AMPHILOCHUS, in Greek legend, a famous seer, son of Amphiaraus and Eriphyle and brother of Alcmaeon. According to some he assisted in the murder of Eriphyle, which, according to others, was carried out by Alcmaeon alone (Apollodorus iii. 6, 7). He took part in the expedition of the Epigoni against Thebes and in the Trojan War. After the fall of Troy he founded, in conjunction with Mopsus, another famous seer, the oracle of Mallos in Cilicia. The two seers afterwards fought for its possession, and both were slain in the combat. Amphilochus is also said to have been killed by Apollo (Strabo xiv. 675, 676). According to another story, he returned to Argos from Troy, but, being dissatisfied with the condition of things there, left it for Acarnania, where he founded Amphilochian Argos on the Ambracian gulf. He was worshipped at Oropus, Athens and Sparta.

Strabo xiv. pp. 675, 676; Thucydides ii. 68; Pausanias i. 34, iii. 15.

AMPHION and ZETHUS, in ancient Greek mythology, the twin sons of Zeus by Antiope. When children, they were exposed on Mount Cithaeron, but were found and brought up by a shepherd. Amphion became a great singer and musician, Zethus a hunter and herdsman (Apollodorus iii. 5). After punishing Lycus and Dirce for cruel treatment of Antiope (q.v.), they built and fortified Thebes, huge blocks of stone forming themselves into walls at the sound of Amphion's lyre (Horace, Odes, iii. 11). Amphion married Niobe, and killed himself after the loss of his wife and children (Ovid, Metam. vi. 270). The brothers were buried in one grave and worshipped as the Dioscuri ``with white horses'' (Eurip. Phoen. 609).

AMPHIOXUS, or LANCELET, the name of small, fish-like, marine creatures, forming the class Cephalochorda, of the phylum Vertebrata. Lancelets are found in brackish or salt water, generally near the coast, and have been referred to several genera and many species. They were first discovered by P. S. Pallas in 1778, who took them to be slugs and described them under the name Limax lanceolatus. The true position in the animal kingdom was first recognized in 1834 by O. G. Costa, who named the genus Branchiostoma, and it has since been dealt with by many writers.

The theoretical interest of Amphioxus depends upon a variety of circumstances. In its manner of development from the egg, and in the constitution of its digestive, vascular, respiratory (branchial), excretory, skeletal, nervous and muscular systems it exhibits what appears to be a primordial condition of vertebrate organization, a condition which is, in fact, partly recapitulated in the course of the embryonic stages of craniate vertebrates. In comparative morphology it provides many illustrations of important biological principles (such, for example, as substitution and change of function of organs), and throws new light upon, or at least points the way to new ideas of, the primitive relations of different organic systems in respect of their function and topography. One of the most puzzling features in its structure, and, at the same time, one of the greatest obstacles to the view that it is essentially primitive and not merely a degenerate creature, is the entire absence of the paired organs of special sense, olfactory, optic and auditory, which are so characteristic of the higher vertebrates. Although it is true that there is a certain amount of gradation in the degree of development to which these organs have attained in the various orders, yet it is hardly sufficient to enable the imagination to bridge over the gap which separates Amphioxus from the lowest fishes in regard to this feature of organization.

Classification.--On account of the absence of anything in the nature of a skull, Amphioxus has been regarded as the type of a division, Acrania, in contrast with the Craniata which comprise all the higher Chordata. The ordinal name for the genera and species of Amphioxus is Cephalochorda, the term referring to the extension of the primary backbone or notochord to the anterior extremity of the body; the family name is Branchiostomidae. The amount of generic divergence exhibited by the members of this family is not great in the mass, but is of singular interest in detail. There are two principal genera--1. Branchiostoma Costa, having paired sexual organs (gonadic pouches); 2. Heteropleuron Kirkaldy, with unilateral gonads. Of these, the former includes two subgenera, Amphioxus (s. str.) Yarrell and Dolichorhynchus Willey. The species belonging to the genus Heteropleuron are divided among the three subgenera Paramphioxus Haeckel, Epigonichthys Peters, and Asymmetron Andrews. The generic characters are based upon definite modifications of form which affect the entire facies of the animals, while the specific diagnoses depend upon minor characters, such as the number of myotomes or muscle-segments.

Habits and Distribution.--With regard to its habits, all that need be said here is that while Amphioxus is an expert swimmer when occasion requires, yet it spends most of its time burrowing in the sand, in which, when at rest, it lies buried with head protruding and mouth wide agape. Its food consists of microscopic organisms and organic particles; these are drawn into the mouth

FIG. 1.--Epigonichthys cultellus from below and from the left side. (Slightly altered from Kirkaldy.) rm and lm, Right and left metapleur; at, atriopore; an, anus; e, ``eyespot'' at anterior end of neurochord projecting beyond the myotomes (my); n, notochord; rgo, gonads of right side only showing through by transparency; go 20, the last gonad; dfr, dorsal fin with fin chambers and fin rays; vfc, ventral fin chambers.

together with currents of water induced by the action of the vibratile cilia which are abundant along special tracts on the sides and roof of the vestibule of the mouth and in the walls of the perforated pharynx (``ciliary ingestion''). Amphioxus favours a littoral habitat, and rarely if ever descends below the 50-fathom line. Species occur in all seas of the temperate, tropical and subtropical zones. The European species, A. lanceolatus, is found in the Black and Mediterranean Seas, and on the coasts of France, Great Britain and Scandinavia, while a closely allied species or subspecies, A. caribaeus, frequents the Caribbean region from Chesapeake to La Plata. A. californiensis occurs on the coast of California, and A. belcheri extends its area of distribution from Queensland through Singapore to Japan. A recently described species, Dolichorhynchus indicus, characterized by the great length of the praeoral lobe or snout, has been dredged in the Indian Ocean. Paramphioxus bassanus occurs on the coast of Australia from Port Phillip to Port Jackson; P. cingalensis at Ceylon. Epigonichthys cultellus (fig. 1) inhabits Torres Strait, and has also been

FIG. 2.--Amphioxus lanceolatus, Yarrell (Branchiostoma lubricum, Coste). (From Ray Lankester.) (1) Lateral view of adult, to show general form, the myomeres, fin rays and gonads. A, Oral tentacles 28 to 32 in full-grown animals, 20 to 24 in half-grown specimens); B, praeoral hood or praeoral epipleur; C, plicated ventral surface of atrial chamber; D1, D17, D26, gonads, twenty-six pairs, coincident with myotomes 10 to 36; E, metapleur or lateral ridge on atrial epipleur; F, atripore, coincident with myotome 36; G1, G15, G34, double ventral fin rays, extending from myotomes 37 to 52, but having no numerical relation to them; H, position of anus, between myotomes 51 and 52; I, notochord, projecting beyond myotomes; K7, K27, K62, myotomes or muscular segments of body-wall, 62 in number; L100, L230, L253, dorsal fin rays, about 250 in number, the hard substance of the ray being absent at the extreme ends of the body (these have no constant numerical relation to the myomeres); M, notochord as seen through the transparent myotomes, the thin double-lined spaces being the connective-tissue septa and the broader spaces the muscular tissue of the myotomes; N, position of brown funnel of left side (atrio-coelomic canal); O, nerve tube resting on notochord.

(2) Dissection of Amphioxus. By a horizontal incision on each side of the body a large ventral area has been separated and turned over, as it were on a hinge, to the animal's left side. The perforated pharyngeal region has then been detached from the adherent epipleura or opercular folds (wall of atrial or branchial chamber) by cutting the fluted pharyngo-pleural membrane d, and separated by a vertical cut from the intestinal region. a, Edge of groove formed by adhesion of median dorsal surface of alimentary canal to sheath of notochord; b, median dorsal surface of alimentary canal; c, left dorsal aorta; cc, single dorsal aorta, formed by union of the two anterior vessels; cc', same vessel resting on intestine; d, cut edge of pharyngo-pleural folds of atrial tunic, really the original outer body-wall before the downgrowth of epipleura; d', atrial tunic (original body-wall) at non-perforate region, cut and turned back so as to expose peri-enteric coelom and intestine r; e', upstanding folds of body-wall (pharyngo-pleural folds) on alternate bars of perforate region of body; f, atrio-coelomic canals or brown funnels (collar-pores of Balanoglossus); g, cavity of a gonad-sac; m, cut musculature of body-wall; n, anus; o, post-atrioporal extension of atrial chamber in form of a tubular caecum; p, atriopore; q, hepatic caecum; r, intestine; s, coelom; t, area of adhesion between alimentary canal and sheath of notochord; v, atrial chamber or branchial cavity; w, post-atrioporal portion of intestine; x, canals of metapleura exposed by cutting; E, probe passing through atriopore into atrial or branchial chamber; FF', probe passing from coelom, where it expands behind the atriopore, into narrower peri-enteric coelom of praeatrioporal region.

(3) Portion of (2) enlarged to show atrio-coelomic canals (``brown funnels'' of Lankester). Lettering as in (2).

(4)Section taken transversely through praeoral region near termination of nerve tube. a, Olfactory ciliated pit on animal's left side, its wall confluent with substance of nerve tube; b, pigment spot (rudimentary eye) on anterior termination of nerve tube; c, first pair of nerves in section; d, fin ray; e, myotome; f, notochord; g, space round myotome (?artifact or coelom); h, subchordal canal (? blood-vessel); i, a symmetrical epipleura of praeoral hood.

found at Ternate. Asymmetron lucayanum is the Bahaman representative of the family, with a subspecies, A. caudatum, in the South Pacific from New Guinea to the Loyalty Islands. The Peruvian species, Branchiostoma elongatum, with nearly eighty myotomes, cannot at present be assigned to its proper subgenus.

External Form.--The following description, unless otherwise stated, refers to A. lanceolatus. Amphioxus is a small fish-like creature attaining a maximum length of about 3 in., semitransparent in appearance, showing iridescent play of colour. The body is narrow, laterally compressed and pointed at both ends. The main musculature can be seen through the thin skin to be divided into about sixty pairs of muscle-segments (myotomes) by means of comma-shaped dissepiments, the myocommas, which stretch between the skin and the central skeletal axis of the body. These myotomes enable it to swim rapidly with characteristic serpentine undulations of the body, the movements being effected by the alternate contraction and relaxation of the longitudinal muscles on both sides. Apparently correlated with this peculiar locomotion is the anatomical fact of the alteration of the myotomes on the two sides. Symmetrical at their first appearance in the embryo, the somites (from which the myotomes are derived) early undergo a certain distortion, the effect of which is to carry the somites of the left side forwards through the length of one half-segment. For example, the twenty-seventh myotome of the left side is placed opposite to the twenty-sixth myocomma of the right side. The back of the body is occupied by a crest, called the dorsal fin, consisting of a hollow ridge, the cavity of which is divided into about 250 compartments or fin chambers, into each of which, with the exception of those near the anterior and posterior end of the body, projects a stout pillar composed of characteristic laminar tissue, the fin ray. The dorsal crest is continued round both extremities, becoming expanded to form the rostral fin in front and the caudal fin behind. Even in external view, careful inspection will show that the body is divisible into four regions, namely, cephalic, atrial, abdominal and caudal. The cephalic region includes the rostrum or praeoral

FIG.--Transverse sections of amphioxus. (From Lankester.) A. Section through region of atrio-coelomic canal s, v. B . Section in front of mouth; the right and left sides are transposed. a, Cavity surrounding fin ray; a', fin ray; b, muscular tissue of myotome; c, nerve- cord; d, notochord; c, left aorta; f thickened ridges of epithelium of praeoral chamber (Rader organ); g, coiled tube lying in a coelomic space on right side of praeoral hood, apparently an artery; h, cuticle of notochord; i, connective-tissue sheath of notochord; k, median ridge of skeletal canal of nerve-cord; l, skeletal canal protecting nerve-cord; m, inter-segmental skeletal septum of myotome; n, subcutaneous skeletal connective tissue; o, ditto of metapleur (this should be relatively thicker than it is); q, subcutaneous connective tissue of ventral surface of atrial wall (not a canal, as supposed by Stieda and others); r, epiblastic epithelium; s gonad-sac containing ova; t, pharyngeal bar in section, one of the pharyngo-pleural fold and coelom; v, atrio-coelomic funnel; w, so-called ``dorsal'' coelom; x, lymphatic space or canal of metapleur; y, sub-pharyngeal vascular trunk; z, blood-vessel (portal vein) on wall of hepatic caecum; aa, space of atrial or branchial chamber; bb, ventral groove of pharynx (anteriorly this takes the form of a ridge); cc, hyperbranchial groove of pharynx; dd, lumen or space of hepatic caecum; ee, narrow coelomic space surrounding hepatic caecum; ff) lining cell-layer of hepatic caecum; gg, inner face of a pharyngeal bar clothed with hypoblast, the outer face covered with epiblast (represented black); hh, a main pharyngeal bar with projecting pharyngeal fold (on which the reference line rests) in section, showing coelomic space beneath the black epiblast; ii, transverse ventral muscle of epipleura; kk, raphe or plane of fusion of two down-grown epipleura; ll, space and nucleated cells on dorsal face of notochord; mm, similar space and cells on its ventral face. lobe and the mouth. As already stated, the notochord extends beyond the mouth to the tip of the rostrum. The mouth consists of two portions, an outer vestibule and an inner apertura oris; the latter is surrounded by a sphincter muscle, which forms the so-called velum. The vestibule of the mouth is the space bounded by the oral hood; this arises by secondary downgrowth of lid-like folds over the true oral aperture, and is provided with a fringe of tentacular cirri, each of which is supported by a solid skeletal axis. The oral hood with its cirri has a special nerve supply and musculature by which the cirri can be either spread out, or bent inwards so that those of one side may interdigitate with those of the other, thus completely closing the entrance to the mouth. The velum is also provided with a circlet of twelve tantacles (in some species sixteen) which hang backwards into the pharynx; these are the velar tentacles. The atrial region extends from the mouth over about two-thirds of the length of the body, terminating at a large median ventral aperture, the atriopore; this is the excurrent orifice for the respiratory current of water and also serves for the evacuation of the generative products. This region

FIG. 4.--Amphioxus lanceolatus laid open ventrally. (After Rathke, slightly altered.) m, Mouth appearing as an elongated slit when relaxed (as in the lamprey); p, perforated pharynx; e, endostyle; g, gonads; l, liver; at, level of atriopore; i, intestine; an, anus. In this species the atrium is produced as an asymmetrical blind pouch behind the atriopore as far as the anus.

is really the branchiogenital region, although the fact is not apparent in external view. The ventral side of the body in the atrial region is broad and convex, in the atrial region is broad and convex, so that the body presents the appearance of a spherical triangle in transverse section, the apex being formed by the dorsal fin and the angles bordered by two hollow folds, the metapleural folds, each of which contains a continuous longitudinal lymph-space, the metapleural canal. In the genus Branchiostoma the metapleural folds terminate symmetrically shortly behind the atriopore, but in Heteropleuron the right metapleur passes uninterruptedly into the median crest of the ventral fin (fig. 1). In this connexion it may also be mentioned that in all cases the right half of the oral hood is directly continuous with the rostral fin (fig. 2). The abdominal region comprises a short stretch of body between atriopore and anus, the termination of the alimentary canal. It is characterized by the presence of a special development of the lophioderm or median fin-system, namely, the ventral fin, which is composed of two portions, a lower keel-like portion, which underlies an upper chambered portion, each chamber containing typically a pair of gelatinous fin rays. Finally, the caudal region comprises the post-anal division of the trunk. The keel of the ventral fin is continued past the anus into the expanded caudal fin, and so it happens that the anal opening is displaced from the middle line to the left side of the fin. In Asymmetron the caudal region is remarkable for the curious elongation of the notochord, which is produced far beyond the last of the myotomes.

Alimentary, Respiratory and Excretory Systems.--Although the function of the two latter systems of organs is the purification of the blood, they are not usually considered together, and it is therefore the more remarkable that their close association in Amphioxus renders it necessary to treat them in common. The alimentary canal is a perfectly straight tube lined throughout by ciliated epithelium. As food particles pass in through the mouth they become enveloped in a slimy substance (secreted by the endostyle) and conveyed down the gut by the action of the vibratile cilia as a continuous food-rope, the peristaltic movements of the gut-wall being very feeble. The first part of the alimentary canal consists of the pharynx or branchial sac, the side walls of which are perforated by upwards of sixty pairs of elongated slits, the gill-clefts. Each primary gill-cleft becomes divided into two by a tongue-bar which grows down secondarily from the upper wall of the cleft and fuses with the ventral wall. New clefts continue to form at the posterior end of the pharynx during the adult life of the animal. The gill-clefts open directly from the cavity of the pharynx into that of the atrium, and so give egress to the respiratory current which enters the mouth with the food (fig. 4). The atrium or atrial chamber is a peripharyngeal cavity of secondary origin effecting the enclosure of the gill-clefts, which in the larva opened directly to the exterior. The atrium is thus analogous to the opercular cavity of fishes and tadpoles, and, as stated above, remains in communication with the exterior by means of the atriopore. The primary and secondary bars which separate and divide the successive gill-clefts from one another are traversed by blood-vessels which run from a simple tubular contractile ventral branchial vessel along the bars into a dorsal aorta. The ventral branchial vessel lies below the hypobranchial groove or endostyle; and is the representative of a heart. As water for respiration streams through the clefts, gaseous interchange takes place between the circulating colourless blood and the percolating water. The pharynx projects freely into the atrium; it is surrounded at the sides and below by the continuous atrial cavity, but dorsally it is held in position in two ways. First, its dorsal wall (which is grooved to form the hyperpharyngeal groove) is closely adherent to the sheath of the notochord; and secondly, the pharynx is attached through the intermediation of the primary bars. These are suspended to the muscular body- wall by a double membrane, called the ligamentum denticulatum, which forms at once the roof of the atrial chamber and the floor of a persistent portion of the original body-cavity or coelom (the dorsal coelomic canal on each side of the pharynx). The ligamentum denticulatum is thus lined on one side by the epiblastic atrial epithelium, and on the other by mesoblastic coelomic epithelium. Now this ligament is inserted into the primary bars some distance below the upper limits of the gill-clefts, and it therefore follows that, corresponding with each tongue-bar, the atrial cavity is produced upward beyond the insertion of the ligament into a series of bags or pockets, which may be called the atrial pouches. At the top of each of these pouches there is a minute orifice, the aperture of a small tubule lying above each pouch in the dorsal coelom. These tubules are the excretory tubules or nephridia. They communicate with the coelom by several openings or nephrostomes, and with the atrium by a single opening in each case, the nephridiopore. It is important to emphasize the fact that in Amphioxus the excretory tubules are co-extensive with the gill-clefts. The perforated pharynx terminates some distance in front of the atriopore. At the level of its posterior end a pair of funnelashaped pouches of the atrium are produced forwards into the dorsal coelom. These are the atrial coelomic funnels or brown funnels, so called on account of the characteristic pigmentation of their walls. There are reasons for supposing that these funnels are vestiges of an ancient excretory system, which has given way by substitution to the excretory tubules described above. In the same region of the body, namely, close behind the pharynx, a large diverticulum is given off from the ventral side of the gut. This is the hepatic caecum (fig. 2,2,q, fig. 4, l), which is quite median at its first origin, but, as it grows in length, comes to lie against the right wall of the pharynx. Although within the atrial cavity, it is separated from the latter by a narrow coelomic space, bounded towards the atrium by coelomic and atrial epithelium. No food passes into the hepatic caecum, which has been de finitely shown on embryological and physiological grounds to be the simplest persistent form of the vertebrate liver.

Nervous System.--As has already been indicated, a solid subcylindrical elastic rod, the notochord, surrounded by a sheath of laminar connective tissue, the cordal sheath, lies above the alimentary canal in contact with its dorsal wall, and extends beyond it both in front and behind to the obtusely pointed extremities of the body. This notochord represents the persistent primordial skeletal axis which, in the higher Craniata (though not so in the lower), gives way by substitution to the segmented vertebral column. Immediately above the notochord there lies another subcylindrical cord, also surrounded by a sheath of connective tissue. This cord is neither elastic nor solid, but consists of nerve tissue, fibres and ganglion cells, surrounding a small central canal. For the sake of uniformity in nomenclature this nerve-cord may be called the neurochord. It is the central nervous system, and contains within itself the elements of the brain and spinal marrow of higher forms. The neurochord tapers towards its posterior end, where it is coextensive with the notochord, but ends abruptly in front, some distance behind the tip of the snout. The neurochord attains its greatest thickness not at its anterior end but some way behind this region; but the central canal dilates at the anterior extremity to form a thin-walled cerebral vesicle, in the front wall of which there is an aggregation of dark pigment cells constituting an eyespot, visible through the transparent skin (fig. 1). There are two pairs of specialized cerebral nerves innervating the praeoral lobe, and provided with peripheral ganglia placed near the termination of the smaller branches. Corresponding with each pair of myotomes, and subject to the same alternation, two pairs of spinal nerves arise from the neurochord, namely, a right and left pair of compact dorsal sensory roots without ganglionic enlargement, and a right and left pair of ventral motor roots composed of loose fibres issuing separately from the neurochord and passing directly to their termination on the muscle-plates of the myotomes. The first dorsal spinal nerve coincides in position with the myocomma which separates the first myotome from the second on each side, and thereafter the successive dorsal roots pass through the substance of the myocommata on their way to the skin; they are therefore septal or intersegmental in position. The ventral roots, on the contrary, are myal or segmental in position. In addition to the cerebral eyespot there are large numbers of minute black pigmented bodies beside and below the central canal of the neurochord, commencing from the level of the third myotome. It has been determined that these bodies are of the nature of eyes (Becheraugen, R. Hesse), each consisting of two cells, a cup-shaped pigment cell and a triangular retinal cell. These may be called the spinal eyes, and it is said that they are disposed in such a way as to receive illumination preferentially from the right side, although this fact has no relation with the side upon which Amphioxus may lie upon the sand. When kept in captivity the animal often lies upon one side on the surface of the sand, but on either side indifferently. Over the cerebral eye there is a small orifice placed to the left of the base of the cephalic fin, leading into a pit which extends from the surface of the body to the surface of the cerebral vesicle; this is known as A. von Kolliker's olfactory pit.

Reproductive System.--The sexes are separate, and the male or female

Fig. 5.--Diagram of embryo gonads, or Amphioxus seen from above in optical section. (Adapted from Hatschek.) pc, Praechordal head-cavity of embryo; cc, collar-cavity (first somite); my, mesodermic somites (myocoelomic or archenteric pouches); ch, notochord with the neural tube (neurochord) lying upon it; np, anterior neuropore; ne, position of posterior neurenteric canal.

gonads, which are exactly similar in outward appearance, occur as a series of gonadic pouches projecting into the atrial cavity at the base of the myotomes (figs. 2, 3, 4). At the breeding season the walls of the pouches burst and the sexual elements pass into the atrium, whence they are discharged through the atriopore into the water, where fertilization takes place.

Development.--The development of Amphioxus possesses many features of interest, and cannot fail to retain its importance as an introduction to the study of embryology. The four principal phases in the development are: (1) Blastula, (2) Gastrula, (3) Flagellate Embryo, (4) Larva. The segmentation or cleavage of the ovum which follows upon fertilization terminates in the achievement of the blastula form, a minute sphere of cells surrounding a central cavity. Then follows the phenomenon of gastrulation, by which one-half of the blastula is invaginated into the other, so as to obliterate the segmentation cavity. The embryo now consists of two layers of cells, epiblast and hypoblast, surrounding a cavity, the archenteron, which opens to the exterior by the orifice of invagination or blastopore. One important fact should

FIG. 6.--Anterior region of two pelagic larvae of A. lanceolatus obtained by the tow-net in 8-10 fathoms, showing the asymmetry of the large lateral sinistral mouth with its ciliated margin cm and the dextral series of simple primary gill-slits (1ps-14ps.) The larvae swim normally like the adult or suspend themselves by their flagella (not shown in the figures) vertically in mid-water. There is nothing in their mode of life which will afford an explanation of the asymmetry which is a developmental phenomenon. Lettering of upper figure.--anp, Anterior neural pore; bc, rudiment of buccal skeleton; c, cilia; cb, ciliated band; cc, ciliated groove; cm, cilia at margin of mouth; gl, external opening of club-shaped gland; Hn, Hatschek's nephridium; lm, left metapleur; n, notochord; pp, praeoral pit; ps, primary gill-slits, 1, 5, and 13; rm, right metapleur showing through. Lettering of'lower fgure.--a, Atrium; al, alimentary canal; bp, blood-vessel; cv, cerebral vesicle; df, dorsal section of myocoel (=fin spaces); e, ``eyespot''; end, endostyle; gl, club-shaped gland; lm, edge of left metapleur; m, lower edge of mouth; n, notochord; nt} pigmented nerve tube; ps, primary gill-slits, 1, 9, and 14; rc, renal cells on atrial floor; rm, edge of right metapleur; so, sense organ opening into praeoral pit; ss, thickenings, the rudiments of the row of secondary gill-slits.

be noted with regard to the gastrula, in which it seems to differ from the gastrulae of invertebrata. After invagination is completed, the embryo begins to elongate, the blastopore becomes narrower, and the dorsal wall of the gastrula loses its convexity, and becomes flattened to form the dorsal plate, the outer layer of which is the primordium of the neurochord and the inner layer the primordium of the notochord. While still within the egg-membrane the epiblastic cells become flagellated, and the gastrula rotates within the membrane. About the eighth hour after commencement of development the membrane ruptures and the oval embryo escapes, swimming by means of its flagella at the surface of the sea for another twenty-four hours, during which the principal organs are laid down, although the mouth does not open until the close of this period. The primordium of the neurochord (neural or medullary plate) referred to above becomes closed in from the surface by the overgrowth of surrounding epiblast, and its edges also bend up, meet, and finally fuse to form a tube, the medullary or neural tube. An important fact to note is that the blastopore is included in this overgrowth of epiblast, so that the neural tube remains for some time in open communication with the archenteron by means of a posterior neurenteric canal. It is still longer before the neural tube completes its closure in front, exhibiting a small orifice at the surface, the anterior neuropore. It is thus possible that the neurenteric canal is due to the conjunction of a posterior neuropore with the blastopore, i.e. it is a complex and not a simple structure. Paired archenteric pouches meanwhile appear at the sides of the axial notochordal tract, the mesoblastic somites. The first of these differs in several respects from those which succeed, and has been called the collar cavity (MacBride). In front of the latter there remains a portion of the archenteron, which becomes constricted off as the head cavity. This becomes divided into two, the right half forming the cavity of the rostrum, while the left acquires an opening to the exterior, and forms the praeoral pit of the larva, which subsequently gives rise to special ciliated tracts in the vestibule of the mouth mentioned above. The larval period commences at about the thirty-sixth hour with the perforation of the mouth, first gill-cleft and anus. The larva is curiously asymmetrical, as many as fourteen gill-clefts appearing in an unpaired series on the right side, while the mouth is a large orifice on the left side, the anus being median. The adult form is achieved by metamorphosis, which cannot be further described here. One point must not be omitted, namely, the homogeny of the endostyle of Amphioxus and the thyroid gland of Craniata.

REFERENCES.--T. Boveri, ``Die Nierencanalchen des Amphioxus,'' Zool Jahrb. Anat. v. (1892), p. 429; T. Felix, ``Beitrage zur Entwickelungsgeschichte der Salmoniden,'' Anat. Hefte Arb. viii. 1897; Amphioxus, p. 333; T. Garbowski, ``Amphioxus als Grundlage der Mesodermtheorie,'' Anat Anz. xiv. (1898), p. 473; R. Hesse, ``Die Sehorgane des Amphioxus,'' Zeitschr. wiss. Zool. lxiii. (1898), p 456; J. W. Kirkaldy, ``A Revision of the Genera and Species of the Branchiostomidae,'' Quart. J. Micr. Sci. xxxvii. (1895), p. 303; E. R. Lankester, ``Contributions to the Knowledge of Amphioxus lanceolatus (Yarrell),'' op. cit., xxix. (1889), p. 365; Lwoff, ``Die Bildung der primaren Keimblatter und die Entstehung der Chorda und des Mesoderms bei den Wirbelthieren,'' Bull. Soc. Moscow (1894); E. W. MacBride, ``The early Development of Amphioxus,'' Quart. J. Micr. Sci. xl. (1897), p. 589, and xliii. (1900); T. H. Morgan and A. P. Hazen, ``The Gastrulation of Amphioxus,'' J. Morphol. xvi. (1900), p. 569; P. Sammassa, ``Studien uber den Einfluss des Dotters auf die Gastrulation und die Bildung der primaren Keimblatter der Wirbelthiere: iv. Amphioxus,'' Arch. f. Entwick. Mech. vii. (1898), p. 1; G. Schneider, ``Einiges uber Resorption und Excretion bei Amphioxus lanceolatus,'' Anat. Anz. xvi. (1899), p. 601; J. Sobotta, ``Die Reifung und Befruchtung des Eies von Amphioxus lanceolatus,'' Arch. mikr. Anat. l. (1897), p. 15; F. E. Weiss, ``Excretory tubules in Amphioxus lanceolatus,'' Quart. J. Micr. Sci. xxxi. (1890), p. 489; A. Willey, Amphioxus and the ancestry of the Vertebrates (1894); ``Remarks on some recent Work on the Protochorda,'' Quart. J. Micr. Sci. xliii. (1899), p. 223; pleuron of New Zealand,'' ib. (1901); E. Burchardt, ``Finer Anatomy of Amphioxus,'' with bibliography, Jena Zeitschr. xxxiv. (1900), p. 719. (A. W.*)

AMPHIPOLIS (mod. Yeni Keui), an ancient city of Macedonia, on the east bank of the river Strymon, where it emerges from Lake Cercinitis, about 3 m. from the sea. Originally a Thracian town, known as 'Ennea `Odoi (``Nine Roads''), it was colonized by Athenians with other Greeks under Hagnon in 437 B.C., previous attempts--in 497, 476 (Schol. Aesch. De fals. leg. 31) and 465--having been unsuccessful. In 424 B.C. it surrendered to the Spartan Brasidas without resistance, owing to the gross negligence of the historian Thucydides, who was with the fleet at Thasos. In 422 B.C. Cleon led an unsuccessful expedition to recover it, in which both he and Brasidas were slain. The importance of Amphipolis in ancient times was due to the fact that it commanded the bridge over the Strymon, and consequently the route from northern Greece to the Hellespont; it was important also as a depot for the gold and silver mines of the district, and for timber, which was largely used in shipbuilding. This importance is shown by the fact that, in the peace of Nicias (421 B.C.), its restoration to Athens is made the subject of a special provision, and that about 417, this provision not having been observed, at least one expedition was made by Nicias with a view to its recovery. Philip of Macedon made a special point of occupying it (357), and under the early empire it became the headquarters of the Roman propraetor, though it was recognized as independent. Many inscriptions, coins, &c., have been found here, and traces of the ancient fortifications and of a Roman aqueduct are visible.

AMPHIPROSTYLE (from the Gr. amfi, on both sides, and prostulos, a portico), the term for a temple (q.v.) with a portico both in the front and in the rear.

AMPHISBAENA (a Greek word, from amfis, both ways, and bainein, to go), a serpent in ancient mythology, beginning or ending at both head and tail alike. Its fabled existence has been utilized by the poets, such as Milton, Pope and Tennyson. In modern zoology it is the name given to the main genus of a family of worm-shaped lizards, most of which inhabit the tropical parts of America, the West Indies and Africa. The commonest species in South America and the Antilles is the sooty or dusky A. fuliginosa. The body of the amphisbaena, from 18 to 20 in. long, is of nearly the same thickness throughout. The head is small, and there can scarcely be said to be a tail, the vent being close to the extremity of the body. The animal lives mostly underground, burrowing in soft earth, and feeds on ants and other small animals. From its appearance, and the ease with which it moves backwards, has arisen the popular belief that the amphisbaena has two heads, and that when the body is cut in two the parts seek each other out and reunite. From this has arisen another popular error, which attributes extraordinary curative properties to its flesh when dried and pulverized.

AMPHITHEATRE (Gr. amfi, around, and theatron, a place for spectators), a building in which the seats for spectators surround the scene of the performance. The word was doubtless coined by the Greeks of Campania, since it was here that the gladiatorial shows for which the amphitheatre was primarily used were first organized as public spectacles. The earliest building of the kind still extant is that at Pompeii, built after 80 B.C. It is called spectacula in a contemporary inscription. The word amphitheatrum is first found in writers of the Augustan age.

In Italy, combats of gladiators at first took place in the forums, where temporary wooden scaffoldings were erected for the spectators; and Vitruvius gives this as the reason why in that country the forums were in the shape of a parallelogram instead of being squares as in Greece. Wild beasts were also hunted in the circus. But towards the end of the Roman republic, when the shows increased both in frequency and in costliness, special buildings began to be provided for them.

The first amphitheatre at Rome was that constructed, 59 B.C., by C. Scribonius Curio. Pliny tells us that Curio built two wooden theatres, which were placed back to back, and that after the dramatic representations were finished, they were turned round, with all the spectators in them, so as to make one circular theatre, in the centre of which gladiators fought; but the story is incredible, and must have arisen from the false translation of amfitheatron by ``double theatre.'' It is uncertain whether Caesar, in 46 B.C., constructed a temporary amphitheatre of wood for his shows of wild beasts; at any rate, the first permanent amphitheatre was built by C. Statilius Taurus in 20 B.C. Probably the shell only was of stone. It was burnt in the great fire of A.D. 64.

We hear of an amphitheatre begun by Caligula and of a wooden structure raised in the year A.D. 57 by Nero; but these were superseded by the Amphitheatrum Flavium (known at least since the 8th century as the Colosseum, from its colossal size), which was begun by Vespasian on the site of an artificial lake included in the Golden House of Nero, and inaugurated by Titus in A.D. 80 with shows lasting one hundred days. It was several times restored by the emperors, having been twice struck by lightning in the 3rd century and twice damaged by earthquake in the 5th. Gladiatorial shows were suppressed by Honorius in A.D. 404, and wild beast shows are not recorded after the reign of Theodoric (d. A.D. 526). In the 8th century Bede wrote Quamdiu stabit Coliseus, stabit et Roma; quando cadet Coliseus, cadet et Roma. A large part of the western arcades seem to have collapsed in the earthquake of A.D. 1349, and their remains were used in the Renaissance as a quarry for building materials (e.g. for the Palazzo di Venezia, the Cancelleria and the Palazzo Farnese).

Rome possesses the remains of a second amphitheatre on the Esquiline, called by the chronologist of A.D. 354 Amphitheatrum Castrense, which probably means the ``court'' or ``imperial'' amphitheatre. Its fine brickwork seems to date from Trajan's reign. It was included by Aurelian in the circuit of his wall. The remains of numerous amphitheatres exist in the various provinces of the empire. The finest are--in Italy, those of Verona (probably of the Flavian period), Capua (built under Hadrian) and Pozzuoli; in France, at Nimes, Arles and Frejus; in Spain, at Italica (near Seville); in Tunisia, at Thysdrus (El-Jem); and at Pola, in Dalmatia. The builders often took advantage of natural features, such as a depression between hills; and ruder structures, mainly consisting of banked-up earth, are found, e.g. at Silchester (Calleva). The amphitheatre at Pompeii (length 444ft., breadth 342 ft., seating capacity 20,000) is formed by a huge embankment of earth supported by a retaining wall and high buttresses carrying arches. The stone seats (of which there are thirty-five rows in three divisions) were only gradually constructed as the means of the community allowed. Access to the highest seats was given by external staircases, and there was no system of underground chambers for wild beasts, combatants, &c.

In contrast to this simple structure the Colosseum represents the most elaborate type of amphitheatre created by the architects of the empire. Its external elevation consisted of four storeys. The three lowest had arcades whose piers were adorned with engaged columns of the three Greek orders. The arches numbered eighty. Those of the basement storey served as entrances; seventy-six were numbered and allotted to the general body of spectators, those at the extremities of the major axis led into the arena, and the boxes reserved for the emperor and the presiding magistrate were approached from the extremities of the minor axis. The higher arcades had a low parapet with (apparently) a statue in each arch, and gave light and air to the passages which surrounded the building. The openings of the arcades above the principal entrances were larger than the rest, and were adorned with figures of chariots. The highest stage was composed of a continuous wall of masonry, pierced by forty small square windows, and adorned with Corinthian pilasters. There was also a series of brackets to support the poles on which the awning was stretched.

The interior may be naturally divided into the arena and the cavea (see annexed plan, which shows the Colosseum at two different levels).

The arena was the portion assigned to the combatants, and derived its name from the sand with which it was strewn, to absorb the blood and prevent it from becoming slippery. Some of the emperors showed their prodigality by substituting precious powders, and even gold dust, for sand. The arena was generally of the same shape as the amphitheatre itself, and was separated from the spectators by a wall built perfectly smooth, that the wild beasts might not by any possibility climb it. At Rome it was faced inside with polished marble, but at Pompeii it was simply painted. For further security, it was surrounded by a metal railing or network, and the arena was sometimes surrounded also by a ditch (euripus), especially on account of the elephants. Below the arena were subterranean chambers and passages, from which wild beasts and gladiators were raised on movable platforms (pegmata) through trap-doors. Such chambers have been found in the amphitheatres of Capua and Pozzuoli as well as in the Colosseum. Means were also provided by which the arena could be flooded when a sea-fight (naumachia) was exhibited, as was done by Titus at the inauguration of the Colosseum.

The part assigned to the spectators was called cavea. It was divided into several galleries (maeniana) concentric with the outer walls, and therefore, like them, of an elliptical form. The place of honour was the lowest of these, nearest to the arena, and called the podium. The divisions in it were larger, so as to be able to contain movable seats. At Rome it was here that the emperor sat, his box bearing the name of suggestus, cubiculum or pulvinar. The senators, principal magistrates, vestal virgins, the provider (editor) of the show, and other persons of note, occupied the rest of the podium. At Nimes, besides the high officials of the town, the podium had places assigned to the principal gilds, whose names are still seen inscribed upon it, with the number of places reserved for each. In the Colosseum there were three maeniana above the podium, separated from each other by terraces (praecinctiones) and walls (baltei), and divided vertically into wedge-shaped blocks (cunei) by stairs. The lowest was appropriated to the equestrian order, the highest was covered in with a portico, whose roof formed a terrace on which spectators found standing room. Numerous passages (vomitoria) and small stairs gave access to them; while long covered corridors, behind and below them, served for shelter in the event of rain. At Pompeii each place was numbered, and elsewhere their extent is defined by little marks cut in the stone. The spectators were admitted by tickets (tesserae), and order preserved by a staff of officers appointed for the purpose.

The height of the Colosseum is about 160 ft.; but the fourth storey in its present form is not earlier in date than the 3rd century A.D. It seems to have been originally of wood, since an inscription of the year A.D. 80 mentions the summum maenianum in ligneis. It is stated in the Notitia Urbis Romae (4th century) that the Colosseum contained 87,000 places; but Huelsen calculates that the seats would accommodate 45,000 persons at most, besides whom 5000 could find standing room. The exaggerated estimate is due to the fact that space was allotted to corporate bodies, whose numbers were taken as data. The greatest length is about 615 ft., and the length of the shorter axis of the ellipse about 510 ft. The dimensions of the arena were 281 ft. by 177 ft.

The following table, giving the dimensions of some of the principal amphitheatres, is based mainly on the figures given by Friedlander (l.c.):--

|----------------------|---------------------|--------------------| | | ENTIRE BUILDING. | ARENA. | | |---------|-----------|----------|---------| | | Greater | Shorter | Greater | Shorter | | | Axis. | Axis. | Axis. | Axis. | | |---------|-----------|----------|---------| | Rome (Colosseum) | 615 | 510 1/2 | 281 | 177 | | Capua | 557 | 458 | 250 | 148 | | Julia Caesarea | 551 | 289 | 459 | 197 | |Italica (Seville) | 514 | 439 1/2 | . . | . . | | Verona | 502 1/2| 403 | 248 | 145 1/2 | | Thysdrus | 488 | 406 | 308 | 197 | | Tarraco | 486 | 390 | 277 | 181 | | Pozzuoli | 482 | 383 | 236 1/2 | 137 3/4 | | Tours | 472 | 406 | 223 | 98 1/2 | | Pola | 449 1/2| 367 1/2 | 230 | 144 1/2 | | Arles | 448 | 352 | 229 | 129 | | Pompeii | 444 | 342 | 218 1/2 | 115 | | Nimes | 440 | 336 | 227 | 126 1/2 | |----------------------|---------|-----------|----------|---------|

BIBLIOGRPHY.--Arts. ``Amphitheatrum'' in Smith's Dictionary of Greek and Roman Antiquities (3rd ed., 1890), and in Daremberg and Saglio's Dictionnaire des antiquites; Friedlander, Darstellungen aus der Sittengeschichte Roms (6th ed., 1888-1890), vol. ii. pp. 551-620; Durm, Geschichte der Baukunst, II.2 (1905), 360 ff. Of older works, J. Lipsius, De Amphitheatris (1585): Carlo Fontana, L'Anfiteatro Flavio (1725); and Maffei, Verona Illustrata, vol. ii. (1826), are worthy of mention. For the amphitheatre at Pompeii, see Mau-Kelsey.

Pompeii, its Life and Art (2nd ed. 1904), chap. 30; for the Colosseum, Middleton, Remains of Ancient Rome, ii. pp. 78-110, and Huelsen's art. ``Flavium Amphitheatrum'' in Pauly-Wossowa, Realencyclopadie. (H. S. J.)

AMPHITRITE, in ancient Greek mythology, a sea-goddess, daughter of Nereus (or Oceanus) and wife of Poseidon. She was so entirely confined in her authority to the sea and the creatures in it, that she was never associated with her husband either for purposes of worship or in works of art, except when he was to be distinctly regarded as the god who controlled the sea. She was one of the Nereids, and distinguishable from the others only by her queenly attributes. It was said that Poseidon saw her first dancing at Naxos among the other Noreids, and carried her off (Schol. on Od. iii. 91). But in another version of the myth, she then fled from him to the farthest ends of the sea, where the dolphin of Poseidon found her, and was rewarded by being placed among the stars (Eratosthenes, Catast. 31). In works of art she is represented either enthroned beside him, or driving with him in a chariot drawn by sea-horses or other fabulous creatures of the deep, and attended by Tritons and Nereids. In poetry her name is often used for the sea.

AMPHITRYON, in Greek mythology, son of Alcaeus, king of Tiryns in Argolis. Having accidentally killed his uncle Electryon, king of Mycenae, he was driven out by another uncle, Sthenelus. He fled with Alcmene, Electryon's daughter, to Thebes, where he was cleansed from the guilt of blood by Creon, his maternal uncle, king of Thebes. Alcmene, who had been betrothed to Amphitryon by her father, refused to marry him until he had avenged the death of her brothers, all of whom except one had fallen in battle against the Taphians. It was on his return from this expedition that Electryon had been killed. Amphitryon accordingly took the field against the Taphians, accompanied by Creon, who had agreed to assist him on condition that he slew the Teumessian fox which had been sent by Dionysus to ravage the country. The Taphians, however, remained invincible until Comaetho, the king's daughter, out of love for Amphitryon cut off her father's golden hair, the possession of which rendered him immortal. Having defeated the enemy, Amphitryon put Comaetho to death and handed over the kingdom of the Taphians to Cephalus. On his return to Thebes he married Alcmene, who gave birth to twin sons, Iphicles being the son of Amphitryon, Heracles of Zeus, who had visited her during Amphitryon's absence. He fell in battle against the Minyans, against whom he had undertaken an expedition, accompanied by the youthful Heracles, to deliver Thebes from a disgraceful tribute. According to Euripides (Hercules Furens) he survived this expedition, and was slain by his son in his madness. Amphitryon was the title of a lost tragedy of Sophocles; the episode of Zeus and Alcmene forms the subject of comedies by Plautus and Moliere. From Moliere's line ``Le veritable Amphitryon est l'Amphitryon ou l'on dine'' (Amphitryon, iii. 5), the name Amphitryon has come to be used in the sense of a generous entertainer, a good host.

Apollodorus ii. 4; Herodotus v. 59; Pausanias viii. 14, ix, 10, 11, 17; Hesiod, Shield, 1-56; Pindar, Pythia, ix. 81.

AMPHORA (a Latin word from Gr. amforeus, derived from amfi, on both sides, and ferein, to bear), a large big-bellied vessel used by the ancient Greeks and Romans for preserving wine, oil, honey, and fruits; and in later times as a cinerary urn. It was so named from usually having an ear or handle on each side of the neck (diota.) It was commonly made of earthenware, but sometimes of stone, glass or even more costly materials. Amphorae either rested on a foot, or ended in a point so that they had to be fixed in the ground. The older amphorae were oval-shaped, such as the vases filled with oil for prizes at the Panathenaic festival, having on one side a figure of Athena, on the other a representation of the contest; the latter were tall and slender, with voluted handles. The first class exhibits black figures on a reddish background, the second red figures on a black ground. The amphora was a standard measure of capacity among both Greeks and Romans, the Attic containing nearly nine gallons, and the Roman about six. In modern botany it is a technical term sometimes denoting the lower part of the capsule called pyxidium, attached to the flower stalk in the form of an urn.

AMPLIATIVE (from Lat. ampliare, to enlarge), an adjective used mainly in logic, meaning ``extending,' or ``adding to that which is already known.'' In Norman law an ``ampliation'' was a postponement of a sentence in order to obtain further evidence.

AMPLITUDE (from Lat. amplus, large), in astronomy, the angular distance of the rising or setting sun, or other heavenly body, from the east or west point of the horizon; used mostly by navigators in finding the variation of the compass by the setting sun. In algebra, if a be a real positive quantity and o a root of unity, then a is the amplitude of the product ao. In elliptic integrals, the amplitude is the limit of integration when the integral is expressed in the form $\int_0^\phi\sqrt{1-N^2\sin^2\phi}d\phi$. The hyperbolic or Gudermannian amplitude of the quantity x is tan-1 (sinh x.) In mechanics, the amplitude of a wave is the maximum ordinate. (See WAVE.)

AMPSANCTUS, or AMSANCTUS (mod. Sorgente Mefita), a small lake in the territory of the Hirpini, IO m. S.E. of Aeclanum, close to the Via Appia. There are now two small pools which exhale carbonic acid gas and sulphuretted hydrogen. Close by was a temple of the goddess Mephitis, with a cave from which suffocating vapours rose, and for this reason the place was brought into connexion with the legends of the infernal regions. Virgil's description (Aeneid, vii. 563) is not, however, very accurate.

AMPTHILL, ODO WILLIAM LEOPOLD RUSSELL, 1ST BARON (1829-1884), British diplomatist and ambassador, was born in Florence on the 20th of February 1829. He was the son of Major- General Lord George William Russell, by Elizabeth Ann, niece of the marquess of Hastings, who was governor-general of India during the final struggle with the Mahrattas. His education, like that of his two brothers--Hastings, who became eventually 9th duke of Bedford, and Arthur, who sat for a generation in the House of Commons as member for Tavistock--was carried on entirely at home, under the general direction of his mother, whose beauty was celebrated by Byron in Beppo. Lady William Russell was as strong-willed as she was beautiful, and certainly deserved to be described as she was by Disraeli, who said in conversation, ``I think she is the most fortunate woman in England, for she has the three nicest sons.'' If it had not been for her strong will it is as likely as not that all the three would have gone through the usual mill of a public school, and have lost half their very peculiar charm. In March 1849 Odo was appointed by Lord Malmesbury attache at Vienna. From 1850 to 1852 he was temporarily employed in the foreign office, whence he passed to Paris. He remained there, however, only about two months, when he was transferred to Vienna. In 1853 he became second paid attache at Paris, and in August 1854 he was transferred as first paid attache to Constantinople, where he served under Lord Stratford de Redcliffe. He had charge of the embassy during his chief's two visits to the Crimea in 1855, but left the East to work under Lord Napier at Washington in 1857. In the following year he became secretary of legation at Florence, but was detached from that place to reside in Rome, where he remained for twelve years, till August 1870. During all that period he was the real though unofficial representative of England at the Vatican, and his consummate tact enabled him to do all, and more than all, that an ordinary man could have done in a stronger position. A reference, however, to his evidence before a committee of the House of Commons in 1871 will make it clear to any unprejudiced reader that those were right who, during the early 'fifties, urged so strongly the importance of having a duly accredited agent at the papal court. The line taken by him during the Vatican council has been criticized, but no fault can justly be found with it. Abreast as he was of the best thought of his time--the brother of Arthur Russell, who, more perhaps than any other man, was its most ideal representative in London society--he sympathized strongly with the views of those who laboured to prevent the extreme partisans of papal infallibility from having everything their own way. But in his capacity of clear-headed observer, whose business it was to reflect the actual truth upon the mind of his government, he was obliged to make it quite clear that they had no chance whatever, and in conversing with those whose opinions were quite unlike his own, such as Cardinal Manning, he seems to have shown that he had no illusions about the result of the long debate. In 1868 Odo Russell married Lady Emily Theresa Villiers, the daughter of Lord Clarendon. In 1870 he was appointed assistant under-secretary at the foreign office, and in November of that year was sent on a special mission to the headquarters of the German army, where he remained till 1871.

It was in connexion with this mission that an episode occurred which at the time threw much discredit upon Gladstone's government. Russia had taken advantage of the collapse of France and her own cordial relations with Prussia to denounce the Black Sea clauses of the treaty of Paris of 1856. Russell, in an interview with Bismarck, pointed out that unless Russia withdrew from an attitude which involved the destruction of a treaty solemnly guaranteed by the powers, Great Britain would be forced to go to war ``with or without allies.'' This strong attitude was effective, and the question was ultimately referred to and settled by the conference which met at London in 1871. Though the result was to score a distinct diplomatic success for the Liberal government, the bellicose method employed wounded Liberal sentiment and threatened to create trouble for the ministry in parliament. On the 16th of February 1871, accordingly, Gladstone, in answer to a question, said that ``the argument used by Mr Odo Russell was not one which had been directed by her Majesty's government,'' that it was used by him ``without any specific instructions or authority from the government,'' but that, at the same time, no blame was to be attached to him, as it was ``perfectly well known that the duty of diplomatic agents requires them to express themselves in that mode in which they think they can best support and recommend the propositions of which they wish to procure acceptance.'' This Gladstonian explanation was widely criticized as an illegitimate attack on Russell. What is certain is that the foreign office and the country profited by Russell's firmness. (See Morley's Gladstone, ii. 534.)

A little later in the same year he received the well-deserved reward of his labours by being made ambassador at Berlin.

During the months he passed at the foreign office he was examined before the committee of the House of Commons, already alluded to, and had an opportunity of stating very distinctly in public some of his views with regard to his profession. ``If you could only organize diplomacy properly,'' he said, ``you would create a body of men who might influence the destinies of mankind and ensure the peace of the world.'' In these words we have the key to the thought and habitual action of one of the best and wisest public servants of the time.

Russell remained at Berlin, with only brief intervals of absence, from the 16th of October 1871 till his death at Potsdam on the 25th of August 1884. He was third plenipotentiary at the Berlin congress, and is generally credited with having prevented, by his tact and good sense, the British prime minister from making a speech in French, which he knew very imperfectly and pronounced abominably. In 1874 Odo Russell received a patent of precedence raising him to the rank of a duke's son, and after the congress of Berlin he was offered a peerage by the Conservative government. This he naturally declined, but accepted the honour in 1881 when it was offered by the Liberals, taking the title of Baron Ampthill. He became a privy councillor in 1872 and was made a G.C.B. somewhat later. At the conference about the Greek frontier, which followed the congress of Berlin, he was the only British representative. During all his long sojourn in the Prussian capital, he did everything that in him lay to bring about close and friendly relations between Great Britain and Germany. He kept on the best of terms with Bismarck, carefully avoiding everything that could give any cause of offence to that most jealous and most unscrupulous minister, whom he, however, did not hesitate to withstand when his unscrupulousness went the length of deliberately attempting to deceive.

He was succeeded as 2nd baron by his son, ARTHUR OLIVER VILLIERS RUSSELL (b. 1869), who rowed in the Oxford eight (1889, 1890, 1891) and became a prominent Unionist politician. He was private secretary to Mr Chamberlain, 1895-1897, and governor of Madras, 1899-1906. In 1904 he acted temporarily as Viceroy of India. (M. G. D.)

AMPTHILL, a market town in the northern parliamentary division of Bedfordshire, England, 44 m. N.N.W. of London by the Midland railway. Pop. of urban district (1901) 2177. It lies on the southern slope of a low range of hills, in a well-wooded district. The church of St Andrew ranges in date from Early English to Perpendicular. It contains a monument to Richard Nicolls (1624-1672), who, under the patronage of the duke of York, brother to Charles II., to whom the king had granted the Dutch North American colony of New Netherland, received the submission of its chief town, New Amsterdam, in 1664, and became its first English governor, the town taking the name of New York. Nicolls perished in the action between the English and Dutch fleets at Solebay, and the ball which killed him is preserved on his tomb. Houghton Park, in the vicinity, contains the ruins of Houghton House, built by Mary, countess of Pembroke, in the time of James I. To this countess Sir Philip Sidney dedicated the Arcadia. Ampthill Park became in 1818 the seat of that Lord Holland in whose time Holland House, in Kensington, London, became famous as a resort of the most distinguished intellectual society. In the park a cross marks the site of Ampthill Castle, the residence of Catherine of Aragon while her divorce from Henry VIII. was pending. A commemorative inscription on the cross was written by Horace Walpole. Brewing, straw-plaiting and lace-making are carried on in Ampthill.

AMPULLA (either a diminutive of amphora, or from Lat. ambo, both, and olla, a pot), a small, narrow-necked, round-bodied vase for holding liquids, especially oil and perfumes. It is the Latin term equivalent to the Greek lekuthos. It was used in ancient times for toilet purposes and anointing the bodies of the dead, being then buried with them. Gildas mentions the use of ampullae as established among the Britons in his time, and St Columba is said to have employed one in the coronation of King Aidan. Both the name and the function of the ampulla have survived in the Western Church, where it still signifies the vessel containing the oil consecrated by the bishop for ritual uses, especially in the sacraments of Confirmation, Orders and Extreme Unction. The word occurs repeatedly in the service of coronation of the English sovereign in connexion with the ancient ceremony of anointing by the archbishop of Canterbury, which is still observed. The ampulla of the regalia of England takes the form of a golden eagle with outspread wings. The most celebrated ampulla in history was that known as la sainte ampoule, in the abbey of St Remi at Reims, from which the kings of France were anointed. According to the legend it had been brought from heaven by a dove for the coronation of Clovis, and at one period the kings of France claimed precedence over all other sovereigns on account of it. It was destroyed at the Revolution. The word ``ampulla'' is used in biology, by analogy from the shape, for a certain portion of the anatomy of a plant or animal.

AMRAM (d. 875), a famous gaon or head of the Jewish Academy of Sura (Persia) in the 9th century. He was author of many ``Responsa,'' but his chief work was liturgical. He was the first to arrange a complete liturgy for the synagogue, and his Prayer-Book (Siddur Rab `Amram) was the foundation of most of the extant rites in use among the Jews. The Siddur was published in Warsaw in two parts (1865).

AMRAOTI, or UMRAWATTEE, a town and district of India, in Berar, Central Provinces. The district was reconstituted in 1905, when that of Ellichpur was incorporated with it. The town has a station 6 m. from Badnera junction on the Great Indian Peninsula line. Pop. (1901) 34,216, showing an increase of 22% in the decade. It is the richest town of Berar, with the most numerous and substantial commercial population. It possesses a branch of the Bank of Bombay, and has the largest cotton mart, where an average of 80,593 bojas of cotton are bought and sold annually. It has also a large grain market, cotton presses, ginning factories and oil mills. Amraoti raw cotton is quoted on the Liverpool Exchange.

The district of Amraoti has an area of 4754 sq. m. In 1901 the population was 630,245, showing a decrease of 4% in the decade; on the area as now constituted it was 809,499. The district is an extensive plain, about 800 ft. above sea-level, the general flatness being only broken by a small chain of hills, running in a north-westerly direction between Amraoti and Chandor, with an average height from 400 to 500 ft. above the lowlands. The principal towns, besides Amraoti, are Karinja, Kolapur, and Badnera, which lies on the Great Indian Peninsula railway, the main line of which crosses the district. Severe drought visited Amraoti in 1899-1900.

AMRAVATI, or AMARAVATI, a ruined city of India in the Guntur district of the Madras presidency, on the south bank of the Kistna river, 62 m. from its mouth. The town is of great interest for the antiquary as one of the chief centres of the Buddhist kingdom of Vengi, and for its stupa (sepulchral monument). Amravati has been identified with Hsuan Tsang's To-na-kie-tse-kia and with the Rahmi of Arab geographers. Subsequent to the disappearance of Buddhism from this region the town became a centre of the Sivaite faith. When Hsuan Tsang visited Amravati in A.D. 639 it had already been deserted for a century, but he speaks in glowing terms of its magnificence and beauty. Very careful and artistic representations of the stupa with its daghoba and interesting rail, pillars and sculptures will be found in Fergusson's Tree and Serpent Worship, and in his History of Indian Architecture (1876). Its elaborate carvings illustrate the life of Buddha. Some are preserved in the British Museum; others in the museum at Madras.

An account by Dr James Burgess was published in 1877 as one of the volumes of the Archaeological Survey of Southern India.

`AMR-IBN-EL-ASS, or `AMR (strictly `AMR B. `AS), one of the most famous of the first race of the Saracen leaders, was of the tribe of Koreish (Qureish). In his youth he was an antagonist of Mahomet. His zeal prompted him to undertake an embassy to the king of Ethiopia, in order to stimulate him against the converts whom he had taken under his protection, but he returned a convert to the Mahommedan faith and joined the fugitive prophet at Medina. When Abu Bekr resolved to invade Syria, he entrusted `Amr with a high command. `Amr soon perceived that his troops were not sufficient for a serious battle. Reinforced by Khalid b. al-Walid, whom Abu Bekr sent in all haste from Irak to Syria, he defeated the imperial troops, commanded by Theodorus, the brother of Heraclius, not far from Ramleh in Palestine, on the 31st of July 634. When Omar became caliph he made Khalid chief commander of the Syrian armies, `Amr remaining in Palestine to complete the submission of that province. It is not certain that `Amr assisted Khalid in the siege of Damascus, but very probable that he took part in the decisive battle of Yarmuk, 20th of August 636. After this battle he laid siege to Jerusalem, in which enterprise he was seconded a year later by Abu Obeida, then chief commander. After the surrender of Jerusalem `Amr began the siege of Caesarea, which, however, was brought to a successful end in September or October 640 by Moawiya, `Amr having obtained Omar's sanction for an expedition against Egypt. Towards the end of 639 he led an army of 4000 Arabs into that country. During his march a messenger from Omar arrived with a letter containing directions to return if he should have received it in Syria, but if in Egypt to advance, in which case all needful assistance would be instantly sent to him. The contents of the letter were not made known to his officers until he was assured that the army was on Egyptian soil, so that the expedition might be continued under the sanction of Omar's orders. Having taken Farama (Pelusium), he advanced to Misr, north of the ancient Memphis, and besieged it and the strong fortress of Babylon for seven months. Although numerous reinforcements arrived, he would have found it very difficult to storm the place previous to the inundation of the Nile but for treachery within the citadel; the Greeks who remained there were either made prisoners or put to the sword. On the same spot `Amr built a city named Fostat (``the encampment''), the ruins of which are known by the name of Old Cairo. The mosque which he erected and called by his own name is described in Asiatic Journal (1890), p. 759. `Amr pursued the Greeks to Alexandria, but finding that it was impossible to take the place by storm, he contented himself with blockading it with the greater part of his army, and reducing the Delta to submission with the rest. At the end of twelve months Alexandria sued for peace, and a treaty was signed on the 8th of November 641. To `Amr acting on Omar's command has been attributed the burning of the famous Alexandrian library. (See LIBRARIES and ALEXANDRIA.) Not only is this act of barbarism inconsistent with the characters of Omar and his general, but the earliest authority for the story is Abulfaragius (Barhebraeus), a Christian writer, who lived six centuries later. After the conquest of Egypt `Amr carried his conquests eastward along the North African coast as far as Barca and even Tripolis. His administration of Egypt was moderate and statesmanlike, and under his rule the produce of the Nile Valley was a constant source of supply to the cities of Arabia. He even reopened a canal at least 80 m. long from the Nile to the Red Sea with the object of renewing communication by sea. Removed from his office by Othman in 647, who replaced him by Ibn abi Sarh, he sided with Moawiya in the contest for the caliphate, and was largely responsible for the deposition of Ali (q.v.) and the establishment of the Omayyad dynasty. (See CALIPHATE, section B.) In 658 he reconquered Egypt in Moawiya's interest, and governed it till his death on the 6th of January 664. In a pathetic speech to his children on his deathbed, he bitterly lamented his youthful offence in opposing the prophet, although Mahomet had forgiven him and had frequently affirmed that ``there was no Mussulman more sincere and steadfast in the faith than `Amr.''

Sir W. Muir, The Caliphate (London, 1891); E. Gibbon,s Decline and Fall; M. J. de Goeje, Memoire sur la conquete de la Syrie (Leiden, 1900); Butler, Arab Conquest of Egypt (Oxford, 1902); art. EGYPT, History, Mahommedan Period.

`AMR IBN KULTHUM, Arabian poet, author of one of the Mo`allakat. Little or nothing is known of his life save that he was a member of the tribe of Taghlib and that he is said to have died of excessive wine-drinking. Some stories of him are told in the Book of Songs (see ABULFARAJ), vol. ix. pp. 181-185.

AMRITSAR, or UMRITSAR, a city and district of British India, in the Lahore division of the Punjab. The city has a station on the North Western railway 32 m. E. of Lahore, its position on which has greatly assisted its development. Amritsar is chiefly notable as the centre of the Sikh religion and the site of the Golden Temple, the chief worshipping place of the Sikhs. Ram Das, the fourth guru, laid the foundations of the city upon a site granted by the emperor Akbar. He also excavated the holy tank from which the town derives its name of Amrita Turas, or Pool of Immortality. It is upon a small island in the middle of this tank that the Golden Temple is now situated. About two centuries afterwards, in the course of the struggle between the Sikhs and the Mahommedans, Ahmad Shah Durani routed the Sikhs at the great battle of Panipat, and on his homeward march he destroyed the town of Amritsar, blew up the temple with gunpowder, filled in the sacred tank with mud, and defiled the holy place by the slaughter of cows. But when Ahmad Shah returned to Kabul the Sikhs rose once more and re-established their religion. Finally the city and surrounding district fell under the sway of Ranjit Singh at Lahore, and passed with the rest of the Punjab into the possession of the British after the second Sikh war. The Golden Temple is so called on account of its copper dome, covered with gold foil, which shines brilliantly in the rays of the Indian sun, and is reflected back from the waters of the lake; but the building as a whole is too squat to have much architectural merit apart from its ornamentation. Marble terraces and balustrades surround the tank, and a marble causeway leads across the water to the temple, whose gilded walls, roof, dome and cupolas, with vivid touches of red curtains, are reflected in the still water. The temple was considerably enriched by the spoils taken by Ranjit Singh in his conquests. The population of Amritsar in 1901 was 162,429. A Sikh college for university education was opened in 1897. The other public buildings include two churches, a town hall and a hospital. Amritsar is famous for its carpet-weaving industry. It was the first mission station of the church of England in the Punjab.

The district is bounded on the N.W. by the river Ravi, on the S.E. by the river Beas, on the N.E. by the district of Gurdaspur, and on the S.W. by the district of Lahore. Amritsar district is a nearly level plain, with a very slight slope from east to west. The banks of the Beas are high, and on this side of the district well-water is not found except at 50 ft. below the surface; while towards the Ravi wells are less than 20 ft. in depth. The only stream passing through the district is the Kirni or Saki, which takes its rise in a marsh in the Gurdaspur district, and after traversing part of the district empties itself into the Ravi. Numerous canals intersect the district, affording ample means of irrigation. The Sind, Punjab and Delhi railway (North Western) and Grand Trunk road, which runs parallel with it, afford the principal means of land communication and traffic. The area of the district is 1601 sq. m.; pop. (1901) 1,023,828, showing an increase of 3% on the previous decade. It is the headquarters of the Sikh religion, containing 264,329 Sikhs as against 280,985 Hindus and 474,976 Mahommedans. The principal crops are wheat, pulse, maize, millet, with some cotton and sugar-cane. There are factories for ginning and pressing cotton.

AMROHA, a town of British India, in the Moradabad district of the United Provinces. It contains the tomb of a Mahommedan saint, Shaikh Saddu, and has been for many centuries a Mahommedan centre. Pop. (1901) 40,077.

AMRUM, or AMROM, a German island in the North Sea, off the coast of Schleswig-Holstein to the south of Sylt. Pop. (1900) 900. It is 6 m. long and 3 m. broad, with an area of 10 1/2 sq. m., and is reached from the mainland by a regular steamboat service to Wittdun, a favourite sea-bathing resort; or at low water by carriage from Fohr. The larger part of Amrum consists of a treeless sandy expanse, but a fringe of rich marshes affords good pasture-land. The principal place is Nebel, connected by a light railway with Wittdun. (See also FRISIAN ISLANDS.)

AMRU'-UL-QAIS, or IMRU'-UL QAIS, IBN HUJR, Arabian poet of the 6th century, the author of one of the Mo`allaat (q.v.), was regarded by Mahomet and others as the most distinguished poet of pre-Islamic times. He was of the kingly family of Kinda, and his mother was of the tribe of Taghlib. While he was still young, his father was killed by the Bani Asad. After this his life was devoted to the attempt to avenge his father's death. He wandered from tribe to tribe to gain assistance, but his attempts were always foiled by the persistent following of the messengers of Mundhir of Hira (Hira). At last he went to the Jewish Arabian prince, Samu`al, left his daughter and treasure with him, and by means of Harith of Ghassan procured an introduction to the Byzantine emperor Justinian. After a long stay in Constantinople he was named phylarch of Palestine, and received a body of troops from Justin II. With these he started on his way to Arabia. It is said that a man of Asad, who had followed him to Constantinople, charged him before the emperor with the seduction of a princess, and that Justin sent him a poisoned cloak, which caused his death at Ancyra.

His poems are contained in W. Ahlwardt's The Divans of the six ancient Arabic Poets (London, 1870), and have been published separately in M`G. de Slane's Le Diwan d'Amro'lkais (Paris, 1837); a German version with life and notes in F. Ruckert's Amrilkais der Dichter und Konig (Stuttgart, 1843). Many stories of his life are told in the Kitab ul-Aghani, vol. viii. pp. 62-77. (G. W. T.)

AMSDORF, NICOLAUS VON (1483-1565), German Protestant reformer, was born on the 3rd of December 1483 at Torgau, on the Elbe. He was educated at Leipzig, and then at Wittenberg, where he was one of the first who matriculated (1502) in the recently founded university. He soon obtained various academical honours, and became professor of theology in 1511. Like Andreas Carlstadt, he was at first a leading exponent of the older type of scholastic theology, but under the influence of Luther abandoned his Aristotelian positions for a theology based on the Augustinian doctrine of grace. Throughout his life he remained one of Luther's most determined supporters; was with him at the Leipzig conference (1519), and the diet of Worms (1521); and was in the secret of his Wartburg seclusion. He assisted the first efforts of the Reformation at Magdeburg (1524), at Goslar (1531) and at Einbeck (1534); took an active part in the debates at Schmalkalden (1537), where he defended the use of the sacrament by the unbelieving; and (1539) spoke out strongly against the bigamy of the landgrave of Hesse. After the death of the count palatine, bishop of Naumburg-Zeitz, he was installed there (January 20, 1542), though in opposition to the chapter, by the elector of Saxony and Luther. His position was a painful one, and he longed to get back to Magdeburg, but was persuaded by Luther to stay. After Luther's death (1546) and the battle of Muhlberg (1547) he had to yield to his rival, Julius von Pflug, and retire to the protection of the young duke of Weimar. Here he took part in founding Jena University (1548); opposed the ``Augsburg Interim'' (1548); superintended the publication of the Jena edition of Luther's works; and debated on the freedom of the will, original sin, and, more noticeably, on the Christian value of good works, in regard to which he held that they were not only useless, but prejudicial. He urged the separation of the High Lutheran party from Melanchthon (1557), got the Saxon dukes to oppose the Frankfort Recess (1558) and continued to fight for the purity of Lutheran doctrine. He died at Eisenach on the 14th of May 1565, and was buried in the church of St George there, where his effigy shows a well-knit frame and sharp-cut features. He was a man of strong will, of great aptitude for controversy, and considerable learning, and thus exercised a decided influence on the Reformation. Many letters and other short productions of his pen are extant in MS., especially five thick volumes of Amsdorfiana, in the Weimar library. They are a valuable source for our knowledge of Luther. A small sect, which adopted his opinion on good works, was called after him; but it is now of mere historical interest.

BIBLIOGRAPHY.--Life, in Th. Pressel, Leben u. ausgewahlte Schrift. der Vater der luth. Kirche, vol. viii. (published separately Elberfeld, 1862, 8vo); J. Meier in Das Leben der Altvater der luth. Kirche, vol, iii. ed. M. Meurer (1863); art. by G. Kawerau in Herzog-Hauck, Realencyk. fur prot. Theologie (3rd ed., Leipzig, 1896).

AMSLER, SAMUEL (1791-1849), Swiss engraver, was born at Schinznach, in the canton of Aargau. He studied his art under Johan Heinrich Lips (1758-1817) and Karl Ernst Hess, at Munich, and from 1816 pursued it in Italy, and chiefly at Rome, till in 1829 he succeeded his former master Hess as professor of copper engraving in the Munich academy. The works he designed and engraved are remarkable for the grace of the figures, and for the wonderful skill with which he retains and expresses the characteristics of the original paintings and statues. He was a passionate admirer of Raphael, and had great success in reproducing his works. Amsler's principal engravings are: ``The Triumphal March of Alexander the Great,'' and a full-length ``Christ,'' after the sculptures of Thorwaldsen and Dannecker; the ``Entombment of Christ,'' and two ``Madonnas'' after Raphael; and the ``Union between Religion and the Arts,'' after Overbeck, his last Work, on which he spent six years.

AMSTERDAM, the chief city of Holland, in the province of North Holland, on the south side of the Y or Ij, an arm of the Zuider Zee, in 52 deg. 22`N. and 4 deg. 53' E. Pop. (1900) 523,557. It has communication by railway and canal in every direction; steam-tramways connect it with Edam, Purmerend, Alkmaar and Hilversum, and electric railways with Haarlem and the sea-side resort of Zandvoort. Amsterdam, the ``dam or dyke of the Amstel'', is so called from the Amstel, the canalized river which passes through the city to the Y. Towards the land the city is surrounded by a semicircular fosse or canal, and was at one time regularly fortified; but the ramparts have been demolished and are replaced by fine gardens and houses, and only one gateway, the Muiderpoort, is still standing. Within the city are four similar canals (grachten) with their ends resting on the Y, extending in the form of polygonal crescents nearly parallel to each other and to the outer canal. Each of these canals marks the line of the city walls and moat at different periods. Lesser canals intersect the others radially, thus virtually dividing the city into a number of islands; whence it has been compared with Venice. The nucleus of the town lies within the innermost crescent canal, and, with the large square, the Dam, in the centre, represents the area of Amsterdam about the middle of the 14th century. At one extremity of the enclosing canal is the Schreijerstoren (1482) or ``Weepers' Tower,'' so called on account of its being at the head of the ancient harbour, and the scene in former days of sorrowful leave-takings. Between this and the next crescent of the Heeren Gracht sprang up, on the east, the labyrinthine quarter where for more than three centuries the large Jewish population has been located, and in the middle of which the painter Rembrandt lived (1640-1656) and the philosopher Spinoza was born (1632). Beyond the Heeren Gracht lie the Keizers Gracht and the Prinsen Gracht respectively, and these three celebrated canals, with their tree-bordered quays and plain but stately old-fashioned houses, form the principal thoroughfares of the city. West of the Prinsen Gracht lies the region called De Jordaan, a corruption of Le Jardin, the name which it acquired from the fact of its streets being called after various flowers. It was formed by the settlement of French refugees here after the revocation of the edict of Nantes. The outermost crescent canal is called the Singel Gracht (girdle canal), and marks the boundary of the city at the end of the 17th century. The streets in the oldest part of Amsterdam are often narrow and irregular, and the sky-line is picturesquely broken by fantastic gables, roofs and towers. The site of the city being originally a peat bog, the foundations of the houses have to be secured by driving long piles (4-20 yds.) into the firm clay below, the palace on the Dam being supported on nearly 14,000 piles. As late as 1822, however, an overladen corn magazine sank into the mud. Modern Amsterdam extends southward beyond the Singel Gracht, and here the houses are often very handsome, while the broad streets are planted with rows of large trees. In the middle of this new region lies the Vondel Park, named after the great national poet Joost van den Vondel (d. 1679), whose statue stands in the park. The Willems Park adjoining was added in later times. In the older part of the town the chief open space is the Zoological Gardens in the north-eastern corner. They belong to a private society called Natura Artis Magistra, and came into existence in 1838. They have, however, been much enlarged since then, and bear a high reputation. In connexion with the gardens there are an aquarium (1882), a library, and an ethnographical and natural history museum. Concerts are given here in summer as well as in the Vondel Park. Close to the Zoological Gardens are the Botanical Gardens, and a small park, also the property of a private society, in which there is a variety theatre. The public squares of the city include the Sophiaplein, with the picturesque old mint-tower; the Rembrandtplein, with a monument (1852) to the painter by Lodswyk Royer; the Thorbeckeplein, with a monument to the statesman, J. R. Thorbecke (1798-1872), and the Leidscheplein, with the large town theatre, rebuilt in 1890-1894 after a fire.

Buildings and Institutions.--The Dam is the vital centre of Amsterdam. All the tramways meet here, and some of the busiest streets, and here too are situated the Nieuwe Kerk and the palace. In the middle of the Dam stands a monument to those who fell in the Belgian revolution of 1830-1831, and called the Metal Cross after the war medals struck at that time. The palace is an imposing building in the classical style, originally built as a town-hall in 1648-1655 by the architect Jacob van Kempen. It was first given up to royalty on the occasion of the visit of the Stadtholder William V. in 1768, and forty years later was appropriated as a royal palace by Louis Bonaparte, king of Holland. But King William I. afterwards formally returned the palace to the city, and the sovereign is therefore actually the city's guest when residing in it. Beautifully decorated on the exterior with gable reliefs by Artus Quellinus (1609-1668) of Antwerp, its great external defect is the absence of a grand entrance. The architectural and ornamental sculpture of the interior is mostly by the same artist, and there are a few interesting pictures, as well as some realistic wall paintings by the 18th century artist Jacob de Wit similar to those in the Huis ten Bosch near the Hague. The great hall is one of the most splendid of its kind in Europe. Like most of the lesser apartments, it is lined with white Italian marble, and in spite of its enormous dimensions the roof is unsupported by pillars. Ancient flags captured in war decorate the walls, and in the middle of the marble floor is a representation of the firmament inlaid in copper. The Nieuwe Kerk (St Catherine's), in which the sovereigns of Holland are crowned, is a fine Gothic building dating from 1408. Internally it is remarkable for its remains of ancient stained glass, fine carvings and interesting monuments, including one to the famous Admiral de Ruyter (d. 1676). A large stained-glass window commemorates the taking of the oath by Queen Wilhelmina in 1898. The new exchange (1901) is a striking building in red brick and stone, and lies a short distance away between the Dam and the fine central station (1889). The Oude Kerk (St Nicholaas), so called, was built about the year 1300, and contains some beautiful stained glass of the 16th and 17th centuries, by Pieter Aertsen of Amsterdam (1508-1575) and others. One window contains the arms of the burgomasters of Amsterdam from 1578 to 1767. Among the monuments are those to various naval heroes, including Admirals van Heemskerk (d. 1607), Sweers (d. 1673) and van der Hulst (d. 1666). The North Church was the last work of the architect Hendrik de Keyser (1565-1621) of Utrecht. The Roman Catholic church of St Nicholaas (1886) was built to replace the accommodation previously afforded by a common dwelling-house, now the Museum Amstelkring of ecclesiastical antiquities. Among the numerous Jewish synagogues, the largest is that of the Portuguese Jews (1670), which is said to be an imitation of the temple of Solomon. Other buildings of interest are the St Antonieswaag, built as a town gate in 1488-1585, and now containing the city archives; the Trippenhuis, built as a private house in 1662, and now the home of the Royal Society of Science, Letters and Fine Arts; the Netherlands Bank (1865-1869), built by the architect W. A. Froger; the new building (1860) of the Seamen's Institute, founded in 1785; the cellular prison; and the so-called Paleis van Volksvlijt, an immense building of iron and glass with a fine garden, built by Dr Samuel Sarphati, and used for industrial exhibitions, the performance of operas, &c. The museums and picture galleries of Amsterdam are of great interest. The Ryks Museum, or state museum, is the first in Holland. It is a large, handsome and finely situated building designed by Dr P. J. H. Cuyper in the Dutch Renaissance style, and erected in 1876-1885. The exterior is decorated with sculptures and tile-work, and internally it is divided, broadly speaking, into a museum of general antiquities below, and the large gallery of pictures of the Dutch and Flemish schools above. The nucleus of this unsurpassed national collection of pictures was formed out of the collections removed hither from the Pavilion at Haarlem, consisting of modern paintings, and from the town-hall, the van der Hoop Museum and the Trippenhuis in Amsterdam. The important van der Hoop collection arose out of bequests by Adrian van der Hoop and his widow in 1854 and 1880; but the most famous pictures in the Ryks Museum are perhaps the three which come from the Trippenhuis, namely, the so-called ``Nightwatch'' and the ``Syndics of the Cloth Hall'' by Rembrandt, andlthe ``Banquet of the Civic Guard,'' by van der Helst. The Trippenhuis gallery consisted of the pictures brought from the Hague by Louis Bonaparte, king of Holland, and belonging to the collection of the Orange family dispersed during the Napoleonic period. The municipal museum contains a collection of furniture, paintings, &c., bequeathed by Sophia Lopez-Suasso (1890), a medico-pharmaceutical collection, and the National Guard Museum. The Joseph Fodor Museum (1860) contains modern French and Dutch pictures. The private collection founded by Burgomaster Jan Six (d. 1702), the friend and patron of Rembrandt, was sold to the state in 1907; the pictures, except the family Rembrandts, are in the Ryks Museum. Close to this is the Willet-Holthuysen Museum (1895) of furniture, porcelain, &c.

Education and Charities.--There are two universities in Amsterdam: the Free University (1880), and the more ancient state university of Amsterdam, originally founded in 1632, but reconstructed in 1887. In addition to the numerous science laboratories the state university possesses a very fine library of about 100,000 volumes, including the Rosenthal collection of over 8000 books on Jewish literature. Modern educational institutions include a school of engineering (1879), a school for teachers (1878) and a school of industrial art (1879). Amsterdam is also remarkable for the number and high character of its benevolent institutions, which are to a large extent supported by voluntary contributions. Among others may be mentioned hospitals for the sick, the aged, the infirm, the blind, the deaf, the dumb, the insane, and homes for widows, orphans, foundlings and sailors. The costumes of the children educated at the different orphanages are varied and picturesque, those of the municipal orphanage being dressed in the city colours of red and black. In the Walloon orphanage are some interesting pictures by van der Helst and others. The Society for Public Welfare (Maatschappij tot nut van het Algemeen), founded in 1785, has for its ob)ect the promotion of the education and improvement of all classes, and has branches in every part of Holland. Among other Amsterdam societies are the Felix Meritis (1776), and the Arti et Amicitiae (1839), whose art exhibitions are of a high order.

Harbour and Commerce.--The first attempt which the city of Amsterdam made to overcome the evils wrought to its trade by the slow formation of the Pampus sandbank at the entrance to the Y from the Zuider Zee, was the construction of the North Holland canal to the Helder in 1825. But the route was too long and too intricate, and in 1876 a much larger and more direct ship canal was built across the isthmus to the North Sea at Ymuiden. The serious rivalry of Rotterdam, especially with regard to the transit trade, and the inadequacy of the Keulsche Vaart, which connected the city with the Rhine, led to the construction in 1892 of the Merwede canal to Gorinchem. Meanwhile a complete transformation took place on the Y to suit the new requirements of the city's trade. The three islands built out into the river serve to carry the railway across the front of the city, and form a long series of quays. On either side are the large East and West docks (1825-1834), and beyond these stretch the lone quays at which the American and East Indian liners are berthed. On the west of the West dock is the timber dock, and east of the East dock is another series of islands joined together so as to form basins and quays, one of which is the State Marine dock (1790-1795) with the arsenal and admiralty offices. Opening out of one of the crescent canals which penetrate the city from the Y is the State Entrepot dock (1900), the free harbour of Amsterdam, where the produce from the Dutch East Indies is stored. On the north side of the Y are the dry docks and the petroleum dock (1880-1890). The principal imports are timber, coal, grain, ore, petroleum and colonial produce. Under the last head fall tobacco, tea, coffee, cocoa, sugar, Peruvian bark and other drugs. Diamond-cutting has long been practised by the Jews and forms one of the most characteristic industries of the city. Other industries include sugar refineries, soap, oil, glass, iron, dye and chemical works; distilleries, breweries, tanneries; tobacco and snuff factories; shipbuilding and the manufacture of machinery and stearine candles. Although no longer the Centre of the banking transactions of the world, the Amsterdam exchange is still of considerable importance in this respect. The celebrated Bank of Amsterdam, founded in 1609, was dissolved in 1796, and the present Bank of the Netherlands was established in 1814 on the model of the Bank of England. The money market is the headquarters of companies formed to promote the cultivation of colonial produce.

History.--In 1204, when Giesebrecht II. of Amstel built a castle there, Amstetdam was a fishing hamlet held in fee by the lords of Amstel of the bishops of Utrecht, for whom they acted as bailiffs. In 1240 Giesebrecht III., son of the builder of the castle, constructed a dam to keep out the sea. To these two, then, the origin of the city may be ascribed. The first mention of the town is in 1275, in a charter of Floris IV., count of Holland, exempting it from certain taxes.

In 1296 the place passed out of the hands of the lords of Amstel, owing to the part taken by Giesebrecht IV. in the murder of Count Floris V. of Holland. Count John (d. 1304), after coming to an understanding with the bishop of Utrecht, bestowed the fief on his brother, Guy of Hainaut. Guy gave the town its first charter in 1300. It established the usual type of government under a bailiff (schout) and judicial assessors (scabini, or schoppenen), the overlord's supremacy being guarded, and an appeal lying from the court of the scabini, in case of their disagreement, to Utrecht. In 1342 more extensive privileges were granted by Count William IV., including freedom from tolls by land and water in return for certain annual dues. In 1482 the town was surrounded with walls; and in the 16th century, during the religious troubles, it received a great increase of prosperity owing to the influx of refugees from Antwerp and Brabant. Amsterdam, influenced by its trading interests, did not join the other towns in revolt against Spain until 1578. In 1587 the earl of Leicester made an unsuccessful attempt to seize it. The great development of Amsterdam was due, however, to the treaty of Westphalia in 1648, by which its rival, Antwerp, was ruined, owing to the closing of the Scheldt. The city held out obstinately against the pretensions of the stadtholders, and in 1650 opened the dykes in order to prevent William II. from seizing it. The same device was successful against Louis XIV. in 1672; and Amsterdam, now reconciled with the stadtholder, was one of the staunchest supporters of William III. against France. After the revocation of the edict of Nantes in 1685 it opened its gates to numerous French refugees; but this hardly compensated it for its losses during the war. In 1787 Amsterdam was occupied by the Prussians, and in 1795 by the French under Pichegru. It was now made the capital of the Batavian Republic and afterwards of the kingdom of Holland. When, in 1810, this was united with the French empire, Amsterdam was recognized officially as the third town of the empire, ranking next after Paris and Rome.

See J. ter Gouw, Geschiedeniss van Amsterdam (3 vols., Amsterdam, 1879-1881), a full history with documents.

AMSTERDAM (NEW AMSTERDAM), an uninhabited and almost inaccessible island in the Indian Ocean, in 37 deg. 47' S., and 77 deg. 34' E., about 60 m. N. of St Paul Island, and nearly midway between the Cape of Good Hope and Tasmania. It is an extinct volcano, rising 2989 ft. from the sea. It was discovered by Anthony van Diemen in 1633, and annexed by France in 1893. It may have been sighted by the companions of Magellan returning to Europe in 1522, and by a Dutch vessel, the ``Zeewolf,'' in 1617. In 1871 the British frigate ``Megaera'' was wrecked here, and most of the 400 persons on board had to remain upwards of three months on the island. The Memoires of a Frenchman, Captain Francois Peron (Paris, 1824), who was marooned three years on the island (1792-1795), are of much interest.

AMSTERDAM, a city of Montgomery county, New York, U.S.A., on the north bank of the Mohawk river, about 33 m. N.W. of Albany. Pop. (1890) 17,336; (1900) 20,929, of whom 5575 were foreign-born; (1910) 31,267. It is served by the New York Central & Hudson River and the West Shore railways, and by the Erie Canal. Hills on both sides of the river command fine views of the Mohawk Valley. Amsterdam has two hospitals, a free public library and St Mary's Institute (Roman Catholic). Manufacturing is the most important industry, and carpets and rugs, hosiery and knit goods are the most important products. In 1905 the city's factory products were valued at $15,007,276 (an increase of 41% over their value in 1900); carpets and rugs being valued at $5,667,742, and hosiery and knit goods (in the manufacture of which Amsterdam ranked third among the cities of the country) at $4,667,022, or 3.4% of the total product of the United States. Among the other manufactures are brushes, brooms, buttons, silk gloves, paper boxes, electrical supplies, dyeing machines, cigars, and wagon and carriage springs. Amsterdam was settled about 1775, and was called Veedersburg until 1804, when its present name was adopted. It was incorporated as a village in 1830, and was chartered as a city in 1885.

AMUCK, RUNNING (or more properly AMOK), the native term for the homicidal mania which attacks Malays. A Malay will suddenly and apparently without reason rush into the street armed with a kris or other weapon, and slash and cut at everybody he meets till he is killed. These frenzies were formerly regarded as due to sudden insanity. It is now, however, certain that the typical amok is the result of circumstances, such as domestic jealousy or gambling losses, which render a Malay desperate and weary of his life. It is, in fact, the Malay equivalent of suicide. ``The act of running amuck is probably due to causes over which the culprit has some amount of control, as the custom has now died out in the British possessions in the peninsula, the offenders probably objecting to being caught and tried in cold blood'' (W. W. Skeat).

Though so intimately associated with the Malay there is some ground for believing the word to have an Indian origin, and the act is certainly far from unknown in Indian history. Some notable cases have occurred among the Rajputs. Thus, in 1634, the eldest son of the raja of Jodhpur ran amuck at the court of Shah Jahan, failing in his attack on the emperor, but killing five of his officials. During the 18th century, again, at Hyderabad (Sind), two envoys, sent by the Jodhpur chief in regard to a quarrel between the two states, stabbed the prince and twenty-six of his suite before they themselves fell.

In Malabar there were certain professional assassins known to old travellers as Amouchi or Amuco. The nearest modern equivalent to these words would seem to be the Malayalim Amar-khan, ``a warrior'' (from amar, ``fight''). The Malayalim term chaver applied to these ruffians meant literally those ``who devote themselves to death.'' In Malabar was a custom by which the zamorin or king of Calicut had to cut his throat in public when he had reigned twelve years. In the 17th century a variation in his fate was made. He had to take his seat, after a great feast lasting twelve days, at a national assembly, surrounded by his armed suite, and it was lawful for anyone to attack him, and if he succeeded in killing him the murderer himself became zamorin (see Alex. Hamilton, ``A new Account of the East Indies,'' in Pinkerton's Voyages and Travels, viii. 374). In 1600 thirty would-be assassins were killed in their attempts. These men were called Amar-khan, and it has been suggested that their action was ``running amuck'' in the true Malay sense. Another proposed derivation for amouchi is Sanskrit amokshya, ``that cannot be loosed,'' suggesting that the murderer was bound by a vow, an explanation more than once advanced for the Malay amuck; but amokshya in such a sense is unknown in Malayalim.

See Sir F. A. Swettenham, Malay Sketches (1895); H. Clifford, Studies in Brown Humanity (1898).

AMULET (Late Lat. amuletum, origin unknown; falsely connected with the Arab. himalah, a cord used to suspend a small Koran from the neck), a charm, generally, but not invariably, hung from the neck, to protect the wearer against witchcraft, sickness, accidents, &c. Amulets have been of many different kinds, and formed of different substances,--stones, metals, and strips of parchment being the most common, with or without characters or legends engraved or written on them. Gems have often been employed and greatly prized, serving for ornaments as well as for charms. Certain herbs, too, and animal preparations have been used in the same way. In setting them apart to their use as amulets, great precautions have been taken that fitting times be selected, stellar and other magic influences propitious, and everything avoided that might be supposed to destroy or weaken the force of the charm. From the earliest ages the Oriental races have had a firm belief in the prevalence of occult evil influences, and a superstitious trust in amulets and similar preservatives against them. There are references to, and apparently correctives of, these customs in the Mosaic injunctions to bind portions of the law upon the hand and as frontlets between the eyes, as well as write them upon the door-posts and the gates; but, among the later Jews especially, the original design and meaning of these usages were lost sight of; and though it has been said that the phylacteries were not strictly amulets, there is no doubt that they were held in superstitious regard. Amulets were much used by the ancient Egyptians, and also among the Greeks and Romans. We find traces of them too in the early Christian church, in the emphatic protests of Chrysostom, Augustine and others against them. The fish was a favourite symbol on these charms, from the word ichthus being the initials of 'Iesous Christos Theou uios soter. A firm faith in amulets still prevails widely among Asiatic nations. Talisman, also from the Arabic, is a word of similar meaning and use, but some distinguish it as importing a more powerful charm. A talisman, whose ``virtues are still applied to for stopping blood and in cases of canine madness,'' figures prominently in, and gives name to, one of Sir Walter Scott's novels.

See also Arpe, De Prodigiis Naturae et Artis Operibus Talismanes et Amuleta dictis (Hamburg, 1717); Ewele, Ueber Amulete (1827); and Koop's Palaeographica Critica, vols. iii. and iv. (1829).

AMUR (known also as the Sakhalin-ula.) a river of eastern Asia, formed by the confluence of the Argun and the Shilka, at Ust-Stryelka, in 53 deg. 19' N. lat. and 120 deg. 30' E. long. Both these rivers come from the south-west: the Argun, or Kerulen as it is called above Lake Kulun (Dalai-nor), through which it flows about half way between its source and Ust-Stryelka, rises in 49 deg. N. lat. and 109 deg. E. long.; the Shilka is formed by the union of the Onon and the Ingoda, both of which have their sources a little farther north-east than the Kerulen (Argun). The Amur proper flows at first in a south-easterly direction for about 800 m., as far as long. 132' E., separating Manchuria from the Amur government; it then turns to the north-east, cuts its way through the Little Khingan mountains in a gorge 2000 ft. wide and 140 m. long, and after a total course of over 1700 m. discharges into the Sea of Okhotsk, opposite to the island of Sakhalin. It is estimated to drain an area of 772,000 sq.