AMMAN AMMONIA. 



141 



Tartar- Mantcheou language, arc to be found in 

 Memoires concernant 1'Histoire, les Sciences et les 

 Arts des Chinois, the tenth part of which sets forth, 

 in fourteen columns, his contributions to the first 

 ten volumes. He wrote, also, Eloges de Moukden, 

 published by Guignes, and the Dictionnaire Tatar- 

 inantcheou-Frangais, published by Langles. 



AMMAN. There were three eminent physiolo- 

 gists of this name. The first, JOHN CONRAD, a 

 native of Schaffhausen, distinguished himself by 

 his success in teaching persons born deaf and dumb 

 to speak, upon which subject he published two 

 treatises. He was born in 1669, and died in 1724. 

 His son, JOHN, was an eminent botanist, and lec- 

 tured on botany at Petersburg. He died in 1740. 

 The third, PAUL, was a native of Breslau, who 

 settled in 1674 at Leipsic, where he gave lectures 

 on physiology, natural history, and botany, and pub- 

 lished several treatises on these subjects. He died 

 in 1691, aged fifty-seven. 



AMMIANUS, Marcellinus ; a Roman historian, of 

 the fourth century after Christ, born at Antioch, in 

 Syria. His work, in thirty-one books (of which 

 only twenty-four are extant), includes the history of 

 the Cajsars, from Nerva to Valens. It may be 

 considered a continuation of Tacitus and Suetonius, 

 and is very interesting and instructive. There is 

 an old and good edition by Gronovins (Leyden, 

 1693), a later one by Ernesti (1773), and the latest 

 by Wagner (Erfurt and Leipsic, 1808, 3 vols.). 



AMMIRATO, Scipio; a distinguished Italian his- 

 torian, born at Lecce, in Naples, 1531. After 

 liaving travelled through Italy, he was employed 

 by the grand duke of Tuscany to write the history 

 of Florence ; for which he was presented to a 

 canonry in the cathedral there. Some of his works, 

 while in this station, are, 1. Arguments, in Italian 

 verse, 4to. Venice, 1548. 2. II Decalione Dialogo 

 del Poeta, 8vo. Naples, 1560. 3. Istorie Floren- 

 tine, dopo la Fondatione di Firenze insino all' 

 anno, 1574. He died in 1601. 



AMMON ; a Libyan deity. Some writers make 

 him a son of Triton; others say, that he was found 

 in a wood, where, with the exception of a sheep, no 

 living thing was to be seen ; and affirm, therefore, 

 tlmt he was the son of this sheep and Jupiter. 

 Others say, that when a boy, he was found by 

 some herdsmen, playing in the sand, between Car- 

 thage and Gyrene ; ana that, as long as he remain- 

 ed on the sand, he continued uttering predictions, 

 but, as soon as they removed him, he became dumb. 

 Finally, it is related, that Bacchus, on his journey 

 Uirough India, being exhausted by heat and thirst, 

 called upon Jupiter for help, not far from Xero- 

 Ijbya ; thereupon a ram appeared, and, stamping 

 with his foot, opened a spring in the sand, and then 

 vanished. This ram he acknowledged as Jupiter 

 himself, paid him divine honours, ana built a temple 

 to him. According to Diodorus Siculus, A. was a 

 king in Libya, whose wife was Rhea, sister to 

 Saturn, and whose mistress was Amalthea, by 

 whom he had Bacchus. The latter built that cele- 

 brated temple to A., where he delivered oracles, 

 not by words, but by signs made by his priests, and 

 where he was exhibited under the form of a ram, 

 or, according to some, of a man with a ram's head 

 or horns. Alexander visited this temple, and was 

 declared, by the priests, a son of the deity. For an 

 account of this old temple of A., in the Oasis of 

 Siwah, see, also, Oasis and Meroe. A.'s horn is a 

 species of fossil, in the form of a ram's horn. A., 

 in Hebrew history, the son of Lot, by his youngest 

 daughter. He was the father of the Ammonites. 



AMMONIA ; an alkaline substance, differing from 

 the other alkalies by its volatility, not being obtain- 



ed pure, except in its gaseous form, and hence 

 called the volatile alkali. It is obtained by mixing 

 together equal weights of dry quick-lime and 

 muriate of ammonia (sal ammoniac), separately 

 powdered, and introducing them into a retort or 

 iron bottle, and applying 'heat. It is a transparent, 

 colourless gas, of little more than half the weight of 

 common air, and has an exceedingly pungent smell, 

 well known under the old name of spirits of harts- 

 horn. It extinguishes flame, and is fatal to life. If 

 is decomposable, by a strong heat, into three parts, 

 by measure, of hydrogen, and one of nitrogen gas. 

 It is rapidly absorbed by water, which dissolves one 

 third of its weight of this gas, or 460 times its bulk, 

 and forms the aqueous ammonia, or aqua ammonice, 

 as it is commonly termed in commerce. The pro- 

 cess for procuring this is merely to connect a retort, 

 or iron bottle, containing the muriate of ammonia 

 and quick-lime (generally slacked), with a common 

 still and refrigeratory, and apply a moderate heat. 

 It is very accurately valued by its specific gravity ; 

 that used in medicine is about 0,950. It is also 

 soluble in alcohol, and is used in medicine under 

 the name of spirits of hartshorn. Ammonia com- 

 bines with the acids, and forms a numerous class of 

 salts : with carbonic acid, it forms the carbonate of 

 ammonia (volatile sal ammoniac), which was formerly 

 prepared from the destructive distillation of animal 

 substances, but is now fabricated, in part, by mixing 

 one proportion of muriate of ammonia with two of 

 carbonate of lime, in a state of dryness, and sub- 

 liming in an earthen pot ; and, more largely, from 

 purified sulphate of ammonia, raixed with one quar- 

 ter of its weight of chalk, finely ground, and pre- 

 viously calcined, introduced into cast-iron retorts, 

 and subjected to a red heat : the carbonate of am- 

 monia, as it is formed, is conveyed by a tube into a 

 leaden or cast-iron receiver, where it is condensed. 

 It is used as a stimulant, usually in the form of 

 smelling-bottles, and also by bakers, to raise their 

 bread lighter and quicker than by yeast alone. 

 With muriatic acid, ammonia forms muriate of am- 

 monia (sal ammoniac). It is found native in fibrous 

 masses and crusts, sublimed into the cracks of lava, 

 among other volcanic matters, about the craters of 

 volcanoes. The muriate of ammonia of commerce, 

 however, is prepared, by a tedious process, from an 

 impure carbonate of ammonia, obtained by the dis- 

 tillation of bones and other animal matters : the 

 carbonate is decomposed by sulphate of lime, and 

 the sulphate of ammonia again by muriate of soda ; 

 and the muriate of ammonia is separated from the 

 sulphate of soda by crystallization, after which it 

 undergoes the process of sublimation two or three 

 times ; and, this being done in rounded vessels, it 

 assumes the form in which we are familiar with 

 it in commerce. The sulphate of ammonia, obtain- 

 ed in procuring gas-lights for illumination from 

 coal, is also made use of in the manufacture of sal 

 ammoniac. It has lately been discovered, that 

 muriate of ammonia exists in the water of the ocean, 

 and that it may be obtained, by sublimation, from 

 the uncrystallizable part called bittern. (Phil. Trans. 

 1822, p. 454.) This salt was formerly imported 

 from Egypt, but is now manufactured in Europe. 

 Great quantities are annually carried from Buch- 

 arian Tartary to Russia and Siberia. Sal am. 

 moniac is applied to many useful purposes. Occa- 

 sionally, it is used in medicine. A considerable 

 portion of it is consumed by dyers, to give bright- 

 ness to some of their colours. It is also employed 

 in the assay of metals, to discover the presence of 

 iron ; and, having the property of rendering lead 

 brittle, is sometimes used in the manufacture of 

 shot. By coppersmiths and tinners, it is used for 



