tations of the more costly starches from this source. The chief use, however, of potato-farina as an edible starch is for adulterating other and more costly preparations. This falsification can readily be detected by microscopic examination, and the accompanying drawings exhibit the appearance under the microscope of the principal starches we have described. Although these starches agree in che mical composition, their value as articles of diet varies considerably, owing to different degrees of digestibility and pleasantness of taste. Arrowroot is found frequently to remain in the stomach of invalids when most other forms of food are rejected, and on this account it has considerable therapeutic value. Being destitute of nitrogen, arrowroot and the other edible starches belong to the force-producing class of foods, and cannot of themselves form a perfect diet. They require to be associated with milk, eggs, meat, or other substances rich ia nitrogenous compounds as articles of diet; and they should not be given to young infants, whose
organs are not suited for the digestion of starchy food.ARROWSMITH, the name of a family of geographers. The first of them, Aaron Arrowsmith, was born in 1750 at Winston in Durham. When about twenty years of age he came to London, and was employed by Gary, the engraver. In 1790 he made himself famous by his large chart of the world on Mercator s projection. Four years later he published another large map of the world on the globular projection, with a companion volume of explanation. The maps of North America and Scotland are the most celebrated of his many later productions. He died in 1823, leaving two sons, Aaron and Samuel, the elder of whom was the compiler of the Eton Comparative Atlas, of a Biblical atlas, and of various manuals of geography. John Arrow- smith, nephew of the elder Aaron, was born at Winston in 1790, and in 1810 joined his uncle in London. In 1834 he published his London Atlas, the best set of maps then in existence. He followed up the atlas with a long series of elaborate and carefully-executed maps, those of Australia, America, Africa, and India being especially valuable. In 1862 he received the gold medal of the Royal Geographical Society, of which body he was one of the founders. He died 2d May 1873.
ARSACIDÆ, the dynasty of Parthian kings, so called from the name of the founder, Arsaces. Very little is known of the circumstances attending the sudden rise of the Parthian power, or of the leader under whom it was effected. He is said by some to have been a Parthian noble, by others to have been a predatory Scythian chief. But at all events, about 250 B.C., when the Selcucid empire of Antiochus II. was distracted by ar> Egyptian war and the successful rebellion of Bactria, t ^e Parthians, hitherto subject and almost unknown to history, revolted, established an independent kingdom, and made their leader, Arsaces, their first sovereign. He is said to have been killed in battle, after a short reign of three years, and the throne was then occupied by his brother, Tiridates, who, like all succeeding sovereigns of Parthia, assumed the name Arsaces as a regal title. The empire increased rapidly in extent and strength, and for a time was the most formidable rival of the Roman power. Towards the close of the 2d century A.D. it had fallen somewhat into decay, as is manifest from the successful Roman invasions under Avidius Cassius and the Emperor Severus; and it finally succumbed to the Persians, who (224 A.D.) revolted under Artaxerxes, and slew in battle Artabanus, the twenty- ninth and last of the Arsacidse. See Parthia.
ARSAMASS, a town in Russia, in the government of Nijni-Novgorod, at the confluence of two minor tributaries of the Volga, the Arsha and Tesha. It has thirty-four churches, three monasteries, several schools, and various benevolent institutions. There are dye-works, soap-fac tories iron- works, and extensive tanneries; and a large trade, stimulated by two annual fairs, is carried on, more especially in sheep-skins and sail-cloth. Population, 1 0,5 1 7.
ARSENAL (supposed to be derived from arx navalis, whence the Romaunt word arthenal, signifying generally a " citadel," though primarily it meant simply a naval citadel 1 ), is an establishment for the construction, repair, receipt, storage, and issue of warlike stores.
A first class arsenal, which can renew the materiel and equipment of a large army must embrace a gun factory, car riage factory, laboratory, and small arms ammunition factory, small arms factory, harness, saddlery, and tent factories, and a powder factory ; in addition it must possess great store-houses. In a second class arsenal the factories would be replaced by workshops. The situation of an arsenal Situate should be governed by strategical considerations. If of the first class, it should be situated at the base of operations and supply; it must be secure from attack, not too near a frontier, and placed so as to draw in readily the resources of the country. The defences of a large arsenal would be Defence provided for by a chain of detached forts and an enceinte of sufficient strength.
The great point in arranging stores is their proper preser- Organiz vation and facility for issue. The branches of an arsenal may tion. be divided into A, Storekeeping ; B, Construction; C, Ad ministration. Under A we should have the following de partments and stores: Departments of issue and receipt, pattern room, armoury department, ordnance or park, har ness, saddlery, and accoutrements, camp equipment, tools and instruments, engineer store, magazines, raw material store, timber yard, breaking up store, unserviceable store. Under B, Gun factory, carriage factory, laboratory, small arms factory, harness and tent factory, powder factory, &c. In a second class arsenal there would be workshops instead of these factories. C. Under the head of administration would be classed the chief director of the arsenal, the superin tendents and assistant-superintendents of the factories and branches of the arsenal. Besides these, who would usually be artillery officers, there would be required managers or fore men (civil and military), non-commissioned officers, arti ficers, workmen, and labourers. In addition a staff of clerks and writers are necessary for all the office work of the establishments. In the manufacturing branches we should want skill, and efficient and economical work, both executive and administrative ; in the storekeeping part, good arrangement, great care, thorough knowledge of all warlike stores, both in their active and passive state, and scrupulous exactness in the custody, issue, and receipt of stores. For fuller details than can be given here the reader is referred to a paper on the organisation of an arsenal, by Lieut. Collen, R.A., in vol. viii. Proceedings It. A. Inst.
In England the Royal Arsenal, Woolwich, manu- Koyal factures and stores the requirements of the army and navy. Aram Under the scheme of army localisation now in force, there are district-issuing stores for the troops for camp equipage, field stores, and reserve ammunition. The con centration of nearly the whole of our military factories and stores at one place, Woolwich, has long been considered an evil, and it has been proposed to establish, at some central spot, a large military depot or arsenal, which should be complementary to Woolwich.
by Lieut. Grover before referred to. As a manufacturing establishment it has existed about 150 years, but as a mili tary post and store depot it possesses a greater antiquity. Before 1805 it was called the "Tower Place" or King s Warren, and the land had been probably acquired in 1667 1 See a very interesting paper, by Lieut. C. E. Grover, R.E., in vol.
vi. Proceedings R. A. Inst., on the Royal Arsenal at Woolwich.