Chapter CXLIV: Act 1895: , may be given to a married woman on applying to (33)

AMMIANUS, MARCELLINUS, the last Roman historian of importance, was born about A.D. 325-330 at Antioch; the date of his death is unknown, but he must have lived till 391, as he mentions Aurelius Victor as the city prefect for that year. He was a Greek, and his enrolment among the protectores domestici (household guards) shows that he was of noble birth. He entered the army at an early age, when Constantius II. was emperor of the East, and was sent to serve under Ursicinus, governor of Nisibis and magister militiae. He returned to Italy with Ursicinus, when he was recalled by Constantius, and accompanied him on the expedition against Silvanus the Frank, who had been forced by the unjust accusations of his enemies into proclaiming himself emperor in Gaul. With Ursicinus he went twice to the East, and barely escaped with his life from Amida or Amid (mod. Diarbekr), when it was taken by the Persian king Shapur (Sapor) II. When Ursicinus lost his office and the favour of Constantius, Ammianus seems to have shared his downfall; but under Julian, Constantius's successor, he regained his position. He accompanied this emperor, for whom he expresses enthusiastic admiration, in his campaigns against the Alamanni and the Persians; after his death he took part in the retreat of Jovian as far as Antioch, where he was residing when the conspiracy of Theodorus (371) was discovered and cruelly put down. Eventually he settled in Rome, where, at an advanced age, he wrote (in Latin) a history of the Roman empire from the accession of Nerva to the death of Valens (96-378), thus forming a continuation of the work of Tacitus. This history (Rerum Gestarum Libri XXXI.) was originally in thirty-one books; of these the first thirteen are lost, the eighteen which remain cover the period from 353 to 378. As a whole it is extremely valuable, being a clear, comprehensive and impartial account of events by a contemporary of soldierly honesty, independent judgment and wide reading. "Ammianus is an accurate and faithful guide, who composed the history of his own times without indulging the prejudices and passions which usually affect the mind of a contemporary" (Gibbon). Although Ammianus was no doubt a heathen, his attitude towards Christianity is that of a man of the world, free from prejudices in favour of any form of belief. If anything he himself inclined to neo-Platonism. His style is generally harsh, often pompous and extremely obscure, occasionally even journalistic in tone, but the author's foreign origin and his military life and training partially explain this. Further, the work being intended for public recitation, some rhetorical embellishment was necessary, even at the cost of simplicity. It is a striking fact that Ammianus, though a professional soldier, gives excellent pictures of social and economic problems, and in his attitude to the non-Roman peoples of the empire he is far more broad-minded than writers like Livy and Tacitus; his digressions on the various countries he had visited are peculiarly interesting. In his description of the empire--the exhaustion produced by excessive taxation, the financial ruin of the middle classes, the progressive decline in the morale of the army--we find the explanation of its fall before the Goths twenty years after his death.

The work was discovered by Poggio, who copied the original MS. Editio princeps (bks. 14-26) by Sabinus, 1474; completed by Accursius, 1533; with variorum notes, by Wagner-Erfurdt, 1808; latest edition of text, Gardthausen, 1874-1875. English translations by P. Holland, 1609; Yonge (Bohn's Classical Library), 1862; also Max Budinger, Ammianus Marcellinus und die Eigenart seines Geschichtswerkes (1895); F. Liesenberg, Die Sprache des Ammianus Marcellinus (1888-1890); T. R. Glover, Life and Letters in the Fourth Century (1901); Abbe Gimazane, Ammianus Marcellinus, sa vie et son oeuvre (Toulouse, 1889), a work containing a number of very doubtful theories. For a criticism of his views on Roman society see S. Dill, Roman Society in the Last Century of the Western Empire (London, 1898).

AMMIRATO, SCIPIONE (1531-1601), Italian historian, born at Lecce, in the kingdom of Naples. His father, intending him for the profession of law, sent him to study at Naples, but his own decided preference for literature prevented him from fulfilling his father's wishes. Entering the church, he resided for a time at Venice, and afterwards engaged in the service of Pope Pius IV. In 1569 he went to Florence, where he was fortunate in securing the patronage and support of Duke Cosimo I., who gave him a residence at the Medici Palace and the Villa Zopaja on the understanding that he should write his Istorie Fiorentine (1600), the work by which he is best known. In 1595 he was made a canon of the cathedral of Florence. He died in 1601. Among the other works of Ammirato, some of which were first published after his death, may be mentioned discourses on Tacitus and genealogies of the families of Naples and Florence.

AMMON, the Graecized name of an Egyptian deity, in the native language Amun, connected by the priests with a root meaning "conceal." He was, to begin with, the local deity of Thebes, when it was an unimportant town on the east bank of the river, about the region now occupied by the temple of Karnak. The XIth dynasty sprang from a family in the Hermonthite nome or perhaps at Thebes itself, and adorned the temple of Karnak with statues. Amenemhe, the name of the founder of the XIIth dynasty, was compounded with that of Amun and was borne by three of his successors. Several Theban kings of the later part of the Middle Kingdom adopted the same name; and when the Theban family of the XVIIth dynasty drove out the Hyksos, Ammon, as the god of the royal city, was again prominent. It was not, however, until the rulers of the XVIIIth dynasty carried their victorious arms beyond the Egyptian frontiers in every direction that Ammon began to assume the proportions of a universal god for the Egyptians, eclipsing all their other deities and asserting his power over the gods of all foreign lands. To Ammon the Pharaohs attributed all their successful enterprises, and on his temples they lavished their wealth and captured spoil.

Ammon is figured of human form, wearing on his head a plain deep circlet from which rise two straight parallel plumes, perhaps representing the tail feathers of a hawk. Two main types are seen: in the one he is seated on a throne, in the other he is standing, ithyphallic, holding a scourge, precisely like Min, the god of Coptos and Chemmis (Akhmim). The latter may be his original form, as a god of fertility, before whom the king ceremoniously breaks up the ground for sowing or cuts the ripe corn. His consort was sometimes called Amaune (feminine of Amun), but more usually Mut, "mother": she was human-headed, wearing the double crown of Upper and Lower Egypt, and their son was Khons (Chon or Chons), a lunar god, represented as a youth wearing the crescent and disk of the moon. A great temple was built to Mut at Karnak not later than the XVIIIth dynasty, and another to Khons not later than the XXth dynasty.

The name of Re, the sun-god, was generally joined to Ammon, especially in his title as "king of the gods": the rule of heaven belonged to the sun-god in the Egyptian cosmos, and this identification with Re was only logical for a supreme deity. Ammon was entitled "lord of the thrones of the two lands," or, more proudly still, "king of the gods." Such indeed was his unquestioned position when suddenly he was overthrown and his worship proscribed. Not even a henotheist fervently worshipping one of many gods, Amenophis (Amenhotp) IV. of the XVIIIth dynasty became the monotheist Akhenaton; discarding all the gods of Egypt, and especially persecuting Ammon the arch-god, he devoted himself to the purer and more sublime worship of Aton, the sun. But he failed to win the permanent adhesion of the people to his reform, or to conciliate or entirely crush the enormously powerful priesthood of Ammon. A few years after the reformer's death, the old cults were re-established and the monuments of Aton studiously defaced. Hymns were then addressed to Amen-re, which are almost monotheistic in expression. The cult of the supreme god spread throughout Egypt and was carried by the Egyptian conquerors into other lands, Syria, Ethiopia and Libya, and was accepted by the natives both in Ethiopia and in the Libyan cases, where civilization was low and Egyptian influence permanent. After the XXth dynasty the centre of power was removed from Thebes, and the authority of Ammon began to wane. In the XXIst dynasty the secondary line of priest kings of Thebes upheld his dignity to the best of their power, and the XXIInd dynasty favoured Thebes: but as the sovereignty weakened the division between Upper and Lower Egypt asserted itself, and thereafter Thebes would have rapidly decayed had it not been for the piety of the kings of Ethiopia towards Ammon, whose worship had long prevailed in their country. Thebes was at first their Egyptian capital, and they honoured Ammon greatly, although their wealth and culture were not sufficient to effect much. Ammon (Zeus) continued to be the great god of Thebes in its decay, and notwithstanding that a nome-capital in the north of the Delta and many lesser temples, from El Hibeh in Middle Egypt to Canopus on the sea, acknowledged Ammon as their supreme divinity, he probably in some degree represented the national aspirations of Upper Egypt as opposed to Middle and Lower Egypt: he also remained the national god of Ethiopia, where his name was pronounced Amane. The priests of Amane at Meroe and Napata, in fact, regulated through his oracle the whole government of the country, choosing the king, directing his military expeditions (and even compelling him to commit suicide, according to Diodorus) until in the 3rd century B.C. Arkamane (Ergamenes) broke through the bondage and slew the priests. Ammon had yet another outburst of glory. There was an oracle of Ammon established for some centuries in Libya, in the distant oasis of Siwa. Such was its reputation among the Greeks that Alexander journeyed thither, after the battle of Issus, and during his occupation of Egypt, in order to be acknowledged the son of the god. The Egyptian Pharaohs of the XVIIIth dynasty had likewise been proclaimed mystically sons of this god, who, it was asserted, had impregnated the queen-mother; and on occasion wore the ram's horns of Ammon, even as Alexander is represented with them on coins.

The Egyptian goose (chenalopex) is figured in the XVIIIth dynasty as sacred to Ammon; but his most frequent and celebrated incarnation was the woolly sheep with curved ("Ammon") horns (as opposed to the oldest native breed with long horizontal twisted horns and hairy coat, sacred to Khnum or Chnumis). It is found as representing Ammon from the time of Amenophis III. onwards.

As king of the gods Ammon was identified by the Greeks with Zeus and his consort Mut with Hera. Khnum was likewise identified with Zeus probably through his similarity to Ammon; his proper animal having early become extinct, Ammon horns in course of time were attributed to this god also.

See Erman, Handbook of Egyptian Religion (London, 1907); Ed. Meyer, art. "Ammon" in Roscher's Lexikon der griechischen und romischen Mythologie; Pietschmann, arts. "Ammon," "Ammoneion" in Pauly-Wissowa, Realencyclopadie; and works on Egyptian religion quoted under EGYPT, section Religion. (F. LL. G.)

AMMON, CHRISTOPH FRIEDRICH VON (1766-1850), German theological writer and preacher, was born at Baireuth. He studied at Erlangen, held various professorships in the philosophical and theological faculties of Erlangen and Gottingen, succeeded Franz Reinhard (1753-1812) in 1813 as court preacher and member of the consistorial court at Dresden, retired from these offices in 1849, and died on the 21st of May 1850. Seeking to establish for himself a middle position between rationalism and supernaturalism, he declared for a "rational supernaturalism," and contended that there must be a gradual development of Christian doctrine corresponding to the advance of knowledge and science. But at the same time he sought, like other representatives of this school of thought, such as K. G. Bretschneider and Julius Wegscheider, to keep in close touch with the historical theology of the Protestant churches. He was a man of great versatility and extensive learning, a philologist and philosopher as well as a theologian, and a very voluminous author. His principal theological work was the Fortbildung des Christenthums zur Weltreligion, in 4 volumes (Leipzig, 1833-1840). Entwurf einer reinbiblischen Theologie appeared in 1792 (2nd ed., 1801), Summa Theologiae Christianae in 1803 (other editions, 1808, 1816, 1830); Das Leben Jesu in 1842, and Die wahre und falsche Orthodoxie in 1849. Von Ammon's style in preaching was terse and lively, and some of his discourses are regarded as models of pulpit treatment of political questions.

See Herzog-Hauck, Realencyklopadie; Otto Pfleiderer, The Development of Theology in Germany since Kant, pp. 89 ff.

AMMONIA (NH3). Salts of ammonia have been known from very early times; thus the term Hammoniacus sal appears in the writings of Pliny (Nat. Hist. xxxi. 39), although it is not known whether the term is identical with the more modern sal-ammoniac (q.v.). In the form of sal-ammoniac, ammonia was known, however, to the alchemists as early as the 13th century, being mentioned by Albertus Magnus, whilst in the 15th century Basil Valentine showed that ammonia could be obtained by the action of alkalies on sal-ammoniac. At a later period when sal-ammoniac was obtained by distilling the hoofs and horns of oxen, and neutralizing the resulting carbonate with hydrochloric acid, the name spirits of hartshorn was applied to ammonia. Gaseous ammonia was first isolated by J. Priestley in 1774 and was termed by him "alkaline air." In 1777 K. W. Scheele showed that it contained nitrogen, and C. L. Berthollet, in about 1785, ascertained its composition.

Ammonia is found in small quantities as the carbonate in the atmosphere, being produced from the putrefaction of nitrogenous animal and vegetable matter; ammonium salts are also found in small quantities in rain-water, whilst ammonium chloride (sal-ammoniac) and ammonium sulphate are found in volcanic districts; and crystals of ammonium bicarbonate have been found in Patagonian guano. Ammonium salts too are found distributed through all fertile soil, in sea- water, and in most plant and animal liquids, and also in urine.

Ammonia can be synthesized by submitting a mixture of nitrogen and hydrogen to the action of the silent electric discharge, the combination, however, being very imperfect. It is obtained by the dry distillation of nitrogenous vegetable and animal products; by the reduction of nitrous acid and nitrites with nascent hydrogen; and also by the decomposition of ammonium salts by alkaline hydroxides or by slaked lime, the salt most generally used being the chloride (sal- ammoniac, q.v.) thus 2NH4Cl + Ca(OH)2 = CaCl2 + 2H2O + 2NH3. It also results on decomposing magnesium nitride (Mg3N2) with water, Mg3N2 + 6H2O = 3Mg(OH)2 + 2NH3. Large quantities of ammonia and ammonium salts are now obtained from the ammoniacal liquor of gas-works.

Ammonia is a colourless gas possessing a characteristic pungent smell and a strongly alkaline reaction; it is lighter than air, its specific gravity being 0.589 (air=1). It is easily liquefied and the liquid boils at -33.7 deg. C., and solidifies at -75 deg. C. to a mass of white crystals. It is extremely soluble in water, one volume of water at 0 deg. C. and normal pressure absorbs 1148 volumes of ammonia (Roscoe and W. Dittmar). All the ammonia contained in an aqueous solution of the gas may be expelled by boiling. It does not support combustion; and it does not burn readily unless mixed with oxygen, when it burns with a pale yellowish-green flame. Ammonia gas has the power of combining with many substances, particularly with metallic halides; thus with calcium chloride it forms the compound CaCl2.8NH3, and consequently calcium chloride cannot be used for drying the gas. With silver chloride it forms two compounds (F. Isambert, Comptes rendus, 1868, lxvi. p. 1259)--one, AgCl.3NH3 at temperatures below 15 deg. C.; the other, 2AgCl.3NH3 at temperatures above 20 deg. C. On heating these substances, ammonia is liberated and the metallic chloride remains. It was by the use of silver chloride ammonia compounds that in 1823 M. Faraday was first able to liquefy ammonia. It can be shown by Isambert's results that the compound AgCl.3NH3 cannot be formed above 20 deg. C., by the action of ammonia on silver chloride at atmospheric pressure; whilst 2AgCl.3NH3, under similar conditions, cannot be formed above about 68 deg. C. Liquid ammonia is used for the artificial preparation of ice. It readily dissolves sodium and potassium, giving in each case a dark blue solution. At a red heat ammonia is easily decomposed into its constituent elements, a similar decomposition being brought about by the passage of electric sparks through the gas. Chlorine takes fire when passed into ammonia, nitrogen and hydrochloric acid being formed, and unless the ammonia be present in excess, the highly explosive nitrogen chloride NCl3 is also produced. With iodine it reacts to form nitrogen iodide. This compound was discovered in 1812 by Bernard Courtois, and was originally supposed to contain nitrogen and iodine only, but in 1840 R. F. Marchand showed that it contained hydrogen, whilst R. Bunsen showed that no oxygen was present. As regards its constitution, it has been given at different times the formulae NI3, NHI2, NH2I, N2H3I3, &c., these varying results being due to the impurities in the substance, owing to the different investigators working under unsuitable conditions, and also to the decomposing action of light. F. D. Chattaway determined its composition as N2H3I3, by the addition of excess of standard sodium sulphite solution, in the dark, and subsequent titration of the excess of the sulphite with standard iodine. The constitution has been definitely determined by O. Silberrad (Jour. of Chem. Soc., 1905, lxxxvii. p. 55) by the interaction of nitrogen iodide with zinc ethyl, the products of the reaction being triethylamine and ammonia; the ammonia liberated was absorbed in hydrochloric acid, and 95% of the theoretical amount of the ammonium chloride was obtained. On these grounds O. Silberrad assigns the formula NH3.NI3 to the compound, and explains the decomposition as taking place, 2NH3.NI3 + 6Zn(C2H5)2 = 6ZnC2H5.I + 2NH3 + 2N(C2H5)3. The hydrogen in ammonia is capable of replacement by metals, thus magnesium burns in the gas with the formation of magnesium nitride Mg3N2, and when the gas is passed over heated sodium or potassium, sodamide, NaNH2, and potassamide, KNH2, are formed.

One of the most characteristic properties of ammonia is its power of combining directly with acids to form salts; thus with hydrochloric acid it forms ammonium chloride (sal-ammoniac); with nitric acid, ammonium nitrate, &c. It is to be noted that H. B. Baker (Journal of Chem. Soc., 1894, lxv. p. 612) has shown that perfectly dry ammonia will not combine with perfectly dry hydrochloric acid, moisture being necessary to bring about the reaction. The aqueous solution of ammonia is very basic in its reactions, and since it is a weak electrolyte, one must assume the solution to contain a certain amount of ammonium hydroxide NH4OH, although it is probably chiefly composed of a solution of ammonia in water. (On the constitution of aqueous ammonia solutions see also Carl Frenzel, Zeit fur angew. Chemie, xxxii. 3, p. 319.) Ammonia finds a wide application in organic chemistry as a synthetic reagent; it reacts with alkyl iodides to form amines (q.v.), with esters to form acid amides (q.v.), with halogen fatty acids to form amino-acids; while it also combines with isocyanic esters to form alkyl ureas and with the mustard oils to form alkyl thioureas. Aldehydes also combine directly with ammonia.

Liquid ammonia possesses strong ionizing powers, and solutions of salts in liquid ammonia have been much studied. For details see E. C. Franklin and C. A. Kraus, Amer. Chem. Jour., 1899, xxi. p. 8; 1900, xxiv. p. 83; 1902, xxviii. p. 277; also Carl Frenzel, Zeits fur Elektrochemie, 1900, vi. p. 477.

The salts produced by the action of ammonia on acids are known as the ammonium salts and all contain the compound radical ammonium (NH4). Numerous attempts have been made to isolate this radical, but so far none have been successful. By the addition of sodium amalgam to a concentrated solution of ammonium chloride, the so-called ammonium amalgam is obtained as a spongy mass which floats on the surface of the liquid; it decomposes readily at ordinary temperatures into ammonia and hydrogen; it does not reduce silver and gold salts, a behaviour which distinguishes it from the amalgams of the alkali metals, and for this reason it is regarded by some chemists as being merely mercury inflated by gaseous ammonia and hydrogen. M. le Blanc has shown, however, that the effect of ammonium amalgam on the magnitude of polarization of a battery is comparable with that of the amalgams of the alkali metals.

Many of the ammonium salts are made from the ammoniacal liquor of gas- works, by heating it with milk of lime and then absorbing the gas so liberated in a suitable acid. (See GAS: Manufacture.)

Ammonium bromide, NH4Br, can be prepared by the direct action of bromine on ammonia. It crystallizes in colourless prisms, possessing a saline taste; it sublimes on heating and is easily soluble in water. On exposure to air it gradually assumes a yellow colour and becomes acid in its reaction.

Ammonium chloride, NH4Cl. (See SAL-AMMONIAC.)

Ammonium fluoride, NH4F, may be obtained by neutralizing ammonia with hydrofluoric acid. It crystallizes in small prisms, having a sharp saline taste, and is exceedingly soluble in water. It decomposes silicates on being heated with them.

Ammonium iodide, NH4I, can be prepared by the action of hydriodic acid on ammonia. It is easily soluble in water, from which it crystallizes in cubes, and also in alcohol. It gradually turns yellow on standing in moist air, owing to decomposition with liberation of iodine.

Ammonium chlorate, NH4ClO3, is obtained by neutralizing chloric acid with either ammonia or ammonium carbonate, or by precipitating barium, strontium or calcium chlorates with ammonium carbonate. It crystallizes in small needles, which are readily soluble in water, and on heating, decompose at about 102 deg. C., with liberation of nitrogen, chlorine and oxygen. It is soluble in dilute aqueous alcohol, but insoluble in strong alcohol.

Ammonium carbonates. The commercial salt is known as sal-volatile or salt of hartshorn and was formerly obtained by the dry distillation of nitrogenous organic matter such as hair, horn, decomposed urine, &c., but is now obtained by heating a mixture of sal-ammoniac, or ammonium sulphate and chalk, to redness in iron retorts, the vapours being condensed in leaden receivers. The crude product is refined by sublimation, when it is obtained as a white fibrous mass, which consists of a mixture of hydrogen ammonium carbonate, NH4.HCO3, and ammonium carbamate, NH2COONH4, in molecular proportions; on account of its possessing this constitution it is sometimes called ammonium sesquicarbonate. It possesses a strong ammoniacal smell, and on digestion with alcohol the carbamate is dissolved and a residue of ammonium bicarbonate is left; a similar decomposition taking place when the sesquicarbonate is exposed to air. Ammonia gas passed into a strong aqueous solution of the sesquicarbonate converts it into normal ammonium carbonate, (NH4)2CO3, which can be obtained in the crystalline condition from a solution prepared at about 30 deg. C. This compound on exposure to air gives off ammonia and passes back to ammonium bicarbonate.

Ammonium bicarbonate, NH4.HCO3, is formed as shown above and also by passing carbon dioxide through a solution of the normal compound, when it is deposited as a white powder, which has no smell and is only slightly soluble in water. The aqueous solution of this salt liberates carbon dioxide on exposure to air or on heating, and becomes alkaline in reaction. The aqueous solutions of all the carbonates when boiled undergo decomposition with liberation of ammonia and of carbon dioxide.

Ammonium nitrate, NH4NO3, is prepared by neutralizing nitric acid with ammonia, or ammonium carbonate, or by double decomposition between potassium nitrate and ammonium sulphate. It can be obtained in three different crystalline forms, the transition points of which are 35 deg. C., 83 deg. C. and 125 deg. C. It is easily soluble in water, a considerable lowering of temperature taking place during the operation; on this account it is sometimes used in the preparation of freezing mixtures. On gentle heating, it is decomposed into water and nitrous oxide. P. E. M. Berthelot in 1883 showed that if ammonium nitrate be rapidly heated the following reaction takes place with explosive violence:--2NH4NO3 = 4H2O + 2N2 + O2.

Ammonium nitrite, NH4NO2, is formed by oxidizing ammonia with ozone or hydrogen peroxide; by precipitating barium or lead nitrites with ammonium sulphate, or silver nitrite with ammonium chloride. The precipitate is filtered off and the solution concentrated. It forms colourless crystals which are soluble in water and decompose on heating, with the formation of nitrogen.

Ammonium phosphates. The normal phosphate, (NH4)3PO4,is obtained as a crystalline powder, on mixing concentrated solutions of ammonia and phosphoric acid, or on the addition of excess of ammonia to the acid phosphate (NH4)2HPO4. It is soluble in water, and the aqueous solution on boiling loses ammonia and the acid phosphate NH4H2PO4 is formed. Diammonium hydrogen phosphate, (NH4)2HPO4, is formed by evaporating a solution of phosphoric acid with excess of ammonia. It crystallizes in large transparent prisms, which melt on heating and decompose, leaving a residue of metaphosphoric acid, (HPO3). Ammonium dihydrogen phosphate, NH4.H2PO4, is formed when a solution of phosphoric acid is added to ammonia until the solution is distinctly acid. It crystallizes in quadratic prisms.

Ammonium sodium hydrogen phosphate, NH4.NaHPO4.4H2O. (See MICROCOSMIC SALT.)

Ammonium sulphate (NH4)2SO4 is prepared commercially from the ammoniacal liquor of gas-works (see GAS: Manufacture) and is purified by recrystallization. It forms large rhombic prisms, has a somewhat saline taste and is easily soluble in water. The aqueous solution on boiling loses some ammonia and forms an acid sulphate. It is used largely as an artificial manure, and also for the preparation of other ammonium salts.

Ammonium persulphate (NH4)2S2O8 has been prepared by H. Marshall (Jour. of Chem. Soc., 1891, lix. p. 777) by the method used for the preparation of the corresponding potassium salt (see SULPHUR). Pure specimens are difficult to obtain. It is very soluble in cold water, a large fall of temperature accompanying solution.

Ammonium sulphide, (NH4)2S, is obtained, in the form of micaceous crystals, by passing sulphuretted hydrogen mixed with a slight excess of ammonia through a well-cooled vessel; the hydrosulphide NH4.HS is formed at the same time. It dissolves readily in water, but is probably partially dissociated in solution. The hydrosulphide NH4.HS can be obtained as a white solid, by mixing well-cooled ammonia with a slight excess of sulphuretted hydrogen. According to W. P. Bloxam (Jour. of Chem. Soc., 1895, lxvii. p. 283), if sulphuretted hydrogen is passed into strong aqueous ammonia at ordinary temperature, the compound (NH4)2S.2NH4HS is obtained, which, on cooling to 0 deg. C. and passing more sulphuretted hydrogen, forms the compound (NH4)2S.12NH4HS. An ice-cold solution of this substance kept at 0 deg. C. and having sulphuretted hydrogen continually passed through it gives the hydrosulphide. Several complex polysulphides of ammonium have been isolated, for details of which see Bloxam's paper quoted above. Compounds are known which may be looked upon as derived from ammonia by the replacement of its hydrogen by the sulpho-group (HSO3); thus potassium ammon-trisulphonate, N(SO3K)3.2H2O, is obtained as a crystalline precipitate on the addition of excess of potassium sulphite to a solution of potassium nitrite, KNO2 + 3K2SO3 + 2H2O = N(SO3K)3 + 4KHO. It can be recrystallized by solution in alkalies. On boiling with water, it is converted, first into the disulphonate NH(SO3K)2 thus, N(SO3K)3 + H2O = NH(SO3K)2 + KHSO4, and ultimately into the monosulphonate NH2.SO3K. The disulphonate is more readily obtained by moistening the nitrilosulphonate with dilute sulphuric acid and letting it stand for twenty-four hours, after which it is recrystallized from dilute ammonia. It forms monosymmetric crystals which by boiling with water yield amidosulphonic acid. (See also E. Divers, Jour. of Chem. Soc., 1892, lxi. p. 943.) Amidosulphonic acid crystallizes in prisms, slightly soluble in water, and is a stable compound.

Ammonia and ammonium salts can be readily detected, in very minute traces, by the addition of Nessler's solution, which gives a distinct yellow coloration in the presence of the least trace of ammonia or ammonium salts. Larger quantities can be detected by warming the salts with a caustic alkali or with quicklime, when the characteristic smell of ammonia will be at once apparent. The amount of ammonia in ammonium salts can be estimated quantitatively by distillation of the salts with sodium or potassium hydroxide, the ammonia evolved being absorbed in a known volume of standard sulphuric acid and the excess of acid then determined volumetrically; or the ammonia may be absorbed in hydrochloric acid and the ammonium chloride so formed precipitated as ammonium chlorplatinate, (NH4)2PtCl6.

AMMONIACUM, or GUM AMMONIAC, a gum-resin exuded from the stem of a perennial herb (Dorema ammoniacum), natural order Umbelliferae. The plant grows to the height of 8 or 9 ft., and its whole stem is pervaded with a milky juice, which oozes out on an incision being made at any part. This juice quickly hardens into round tears, forming the "tear ammoniacum" of commerce. "Lump ammoniacum," the other form in which the substance is met with, consists of aggregations of tears, frequently incorporating fragments of the plant itself, as well as other foreign bodies. Ammoniacum has a faintly fetid, unpleasant odour, which becomes more distinct on heating; externally it possesses a reddish-yellow appearance, and when the tears or lumps are freshly fractured they exhibit a waxy lustre. It is chiefly collected in central Persia, and comes to the European market by way of Bombay. Ammoniacum is closely related to asafetida and galbanum (from which, however, it differs in yielding no umbelliferone) both in regard to the plant which yields it and its therapeutical effects. Internally it is used in conjunction with squills in bronchial affections; and in asthma and chronic colds it is found useful, but it has no advantages over a number of other substances of more constant and active properties (Sir Thomas Fraser). Only the "tear ammoniacum" is official.

African ammoniacum is the product of a plant said to be Ferula tingitana, which grows in North Africa; it is a dark coloured gum-resin, possessed of a very weak odour and a persistent acrid taste.

AMMONITES, or the "children of Ammon," a people of east Palestine who, like the Moabites, traced their origin to Lot, the nephew of the patriarch Abraham, and must have been regarded, therefore, as closely related to the Israelites and Edomites. Both the Ammonites and Moabites are sometimes spoken of under the common name of the children of Lot (Deut. ii. 19; Ps. lxxxiii. 8); and the whole history shows that they preserved throughout the course of their national existence a sense of the closest brotherhood. According to the traditions, the original territory of the two tribes was the country lying immediately on the east of the Dead Sea, and of the lower half of the Jordan, having the Jabbok for its northern boundary; and of this tract the Ammonites laid claim to the northern portion between the Arnon and the Jabbok, out of which they had expelled the Zamzummim (Judg. xi. 13; Deut. ii. 20 sqq.; cf. Gen. xiv. 5), though apparently it had been held, in part at least, conjointly with the Moabites, or perhaps under their supremacy (Num. xxi. 26, xxii. 1; Josh. xiii. 32). From this their original territory they had been in their turn expelled by Sihon, king of the Amorites, who was said to have been found by the Israelites, after their deliverance from Egypt, in possession of both Gilead and Bashan, that is, of the whole country on the left bank of the Jordan, lying to the north of the Arnon (Num. xxi. 13). By this invasion, as the Moabites were driven to the south of the Arnon, which formed their northern boundary from that time, so the Ammonites were driven out of Gilead across the upper waters of the Jabbok where it flows from south to north, which henceforth continued to be their western boundary (Num. xxi. 24; Deut. ii. 37, iii. 16). The other limits of the Ammonitis, or country of the Ammonites ('Lmmanitis chora, 2 Mac. iv. 26), there are no means of exactly defining. On the south it probably adjoined the land of Moab; on the north it may have met that of the king of Geshur (Josh. xii. 5); and on the east it probably melted away into the desert peopled by Amalekites and other nomadic races.

The chief city of the country, called Rabbah, or Rabbath of the children of Ammon, i.e. the metropolis of the Ammonites (Deut. iii. 11), and Rabbathammana by the later Greeks (Polyb, v. 7. 4), whose name was changed into Philadelphia by Ptolemy Philadelphus, a large and strong city with an acropolis, was situated on both sides of a branch of the Jabbok, bearing at the present day the name of Nahr `Amman, the river of Ammon, whence the designation "city of waters" (2 Sam. xii. 27); see Survey of E. Pal (Pal. Explor. Fund), pp. 19 sqq. The ruins called Amman by the natives are extensive and imposing. The country to the south and east of Amman is distinguished by its fertility; and ruined towns are scattered thickly over it, attesting that it was once occupied by a population which, however fierce, was settled and industrious, a fact indicated also by the tribute of corn paid annually to Jotham (2 Chron. xxvii. 5).

The traditional history of Ammon as related in the Old Testament is not free from obscurity, due to the uncertain date of the various references and to the doubt whether the individual details belong to the particular period to which each is ascribed. (See further MOAB.) From the Assyrian inscriptions we learn that the Ammonite king Ba'sa (Baasha) (son) of Ruhubi, with 1000 men joined Ahab and the Syrian allies against Shalmaneser II. at the battle of Karkar in 854. In 734 their king Sanip(b)u was a vassal of Tiglathpileser IV., and his successor, P(b)udu-ilu, held the same position under Sennacherib and Esarhaddon. Somewhat later, their king Amminadab was among the tributaries who suffered in the course of the great Arabian campaign of Assurbanipal. With the neighbouring tribes, the Ammonites helped the Babylonian monarch Nebuchadrezzar against Jehoiakim (2 Kings xxiv. 2); and if they joined Zedekiah's conspiracy (Jer. xxvii. 3), and were threatened by the Babylonian army (Ezek. xxi. 20 sqq.), they do not appear to have suffered punishment at that period, perhaps on account of a timely submission. When, after the destruction of Jerusalem, the fugitive Jews were again gathered together, it was at the instigation of Baalis, king of Ammon, that Gedaliah, the ruler whom Nebuchadrezzar had appointed over them, was murdered, and new calamities were incurred (Jer. xl. 14); and when Nehemiah prepared to rebuild the walls of Jerusalem an Ammonite was foremost in opposition (Neh. ii. 10, 19, iv. 1-3).1 True to their antecedents, the Ammonites, with some of the neighbouring tribes, did their utmost to resist and check the revival of the Jewish power under Judas Maccabaeus (1 Macc. v. 6; cf. Jos. Ant. Jud. xii. 8. 1.). The last notice of them is in Justin Martyr (Dial. cum Tryph. sec. 119), where it is affirmed that they were still a numerous people. The few Ammonite names that have been preserved (Nahash, Hanun, and those mentioned above, Zelek in 2 Sam. xxiii. 37 is textually uncertain) testify, in harmony with other considerations, that their language was Semitic, closely allied to Hebrew and to the language of the Moabites. Their national deity was Moloch or Milcon. (See MOLOCH.) (S. A. C.)

1 The allusions in Jer. xlix. 1-6; Zeph. ii. 8-11; Ezek. xxi. 28- 32; Judg. xi. 12-28, have been taken to refer to an Ammonite occupation of Israelite territory after the deportation of the east Jordanic Israelites in 734, but more probably belong to a later event. The name Chephar-Ammoni (in Benjamin; Josh. xviii. 24) seems to imply that the "village" became a settlement of "Ammonites." Some light is thrown upon the obscure history of the post-exile period by the references to the mixed marriages which aroused the reforming zeal of Ezra and culminated in the exclusion of Ammon and Moab from the religious community--on the ground of incidents which were ascribed to the time of the "exodus" (Deut. xxiii. 3 sqq.; Ezr. ix. 1 sqq.; Neh. xiii. 1 sqq.).

AMMONIUS GRAMMATICUS, the supposed author of a treatise entitled Peri omoion kai dialoron lfxeon (On the Differences of Synonymous Expressions), of whom nothing is known. He was formerly identified with an Egyptian priest who, after the destruction of the pagan temple at Alexandria (389), fled to Constantinople, where he became the tutor of the ecclesiastical historian Socrates. But it seems more probable that the real author was Herennius Philo of Byblus, who was born during the reign of Nero and lived till the reign of Hadrian, and that the treatise in its present form is a revision prepared by a later Byzantine editor, whose name may have been Ammonius.

Text by Valckenaer, 1739, Schafer, 1822; Kopp, De Ammonii . . . Distinctionibus Synonymicis, 1883.

AMMONIUS HERMIAE (5th century A.D.), Greek philosopher, the son of Hermias or Hermeias, a fellow-pupil of Proclus. He taught at Alexandria, and had among his scholars Asclepius, John Philoponus, Damascius and Simplicius. His commentaries on Plato and Ptolemy are lost. Those on Aristotle are all that remain of his reputedly numerous writings. Of the commentaries we have--(1) one on the Isagoge of Porphyry (Venice, 1500 fol.); (2) one on the Categories (Venice, 1503 fol.), the authenticity of which is doubted by Brandis; (3) one on the De Interpretatione (Venice, 1503 fol.). They are printed in Brandis's scholia to Aristotle, forming the fourth volume of the Berlin Aristotle; they are also edited (1891-1899) in A. Busse's Commentaria in Aristot. Graeca. The special section on fate was published separately by J. C. Orelli, Alex. Aphrod., Ammonii, et aliorum de Fato quae supersunt (Zurich, 1824). A life of Aristotle, ascribed to Ammonius, but with more accuracy to John Philoponus, is often prefixed to editions of Aristotle. It has been printed separately, with Latin translation and scholia, at Leiden, 1621, at Helmstadt, 1666, and at Paris, 1850. Other commentaries on the Topics and the first six books of the Metaphysics still exist in manuscript. Of the value of the logical writings of Ammonius there are various opinions. K. Prantl speaks of them with great, but hardly merited, contempt.

For a list of his works see J. A. Fabricius, Bibliotheca Graeca, v. 704-707: C. A. Brandis, Uber d. Reihenf. d. Bucher d. Aristot. Org., 283 f.; K. Prantl, Gesch. d. Logik, i. 642.

AMMONIUS SACCAS (3rd century A.D.), Greek philosopher of Alexandria, often called the founder of the neo-Platonic school. Of humble origin, he appears to have earned a livelihood as a porter; hence his nickname of "Sack-bearer" (Sakkas, for sakkoforos.) The details of his life are unknown, insomuch that he has frequently been confused with a Christian philosopher of the same name. Eusebius (Church History, vi. 19), who is followed by Jerome, asserts that he was born a Christian, remained faithful to Christianity throughout his life, and even produced two works called The Harmony of Moses and Jesus and The Diatessaron, or Harmony of the Four Gospels, which is said by some to exist in a Latin version by Victor, bishop of Capua. Porphyry, quoted by Eusebius, ib. vi. 19. 6, however, says that he apostatized in later life and left no writings behind him. There seems no reason, therefore, to doubt that Eusebius is here referring to the Christian philosopher. After long study and meditation, Ammonius opened a school of philosophy in Alexandria. His principal pupils were Herennius, the two Origens, Cassius Longinus and Plotinus. As he designedly wrote nothing, and, with the aid of his pupils, kept his views secret, after the manner of the Pythagoreans, his philosophy must be inferred mainly from the writings of Plotinus. As Zeller points out, however, there is reason to think that his doctrines were rather those of the earlier Platonists than those of Plotinus. Hierocles, writing in the 5th century A.D., states that his fundamental doctrine was an eclecticism, derived from a critical study of Plato and Aristotle. His admirers credited him with having reconciled the quarrels of the two great schools. His death is variously given between A.D. 240 and 245. See NEO-PLATONISM, ORIGEN.

BIBLIOGRAPHY.--C. Rosler, De commentitiis philosophiae Ammoniaceae fraudibus et noxis (Tubingen, 1786); L. J. Dehaut, Essai historique sur la vie et la doctrine d' Ammonius Saccas (Brussels, 1856); E. Zeller, "Ammonius Saccas und Plotinus," Arch. f. Gesch. d. Philos. vii., 1894, pp. 295-312; E. Vacherot, Hist. crit. de l'ecole d'Alexandrie (Paris, 1846); T. Whittaker, The Neo-platonists (Camb., 1901); Eusebius, Hist. Eccles., trans. A. C. M'Giffert (Oxford and New York, 1890), notes on passages quoted above.

AMMUNITION, a military term (derived, through the French, from Lat. munire, to provide), for consumable stores used in attack or defence, such as rifle cartridges, cartridges, projectiles, igniting tubes and primers for ordnance, &c.

The components of ammunition intended for rifles and ordnance may be divided into (a) explosives and propellants (see EXPLOSIVES and GUNPOWDER), (b) projectiles of all kinds, and (c) cartridges. The military classification of explosives differs somewhat from that of the Explosives