France, was born at Toulon in 1718, and died in 1794, aged 77. He arrived at Macao in 1750, was invited to Pekin in 1751 by the emperor of China, and remained in that capital forty-three years. By continued application he soon became acquainted with the Chinese and Tartar languages, and sent from time to time the result of his attainments and collections to France, His works are, a Chinese Poem in praise of the city of Moukden, by the emperor Kien Long, translated into French, 8vo. Paris, 1770. The Chinese Military Art, 4to. Paris, 1772. Letters on the Chinese Characters. On the Music of the Chinese. The Life of Confucius. Dictionnaire Tartar Mantcheou François, 3 vols. 4to. Paris, 1789. AMIRANTE ISLANDS, a small group of isles in the Indian Ocean, lying to the south-west of the Seychelles, and about thirteen degrees to the north of Madagascar. They possess very little either of culture or population. AMIRANTE, in the Spanish polity, a great officer of state, answering to our lord high-ad miral. AMISS', n. & adv. Ang. Sax. missian, to err; Dutch missen, to err; German missen, to want. Miss, as well as amiss, is found in Chaucer. Error, fault, deceitfulness, deficiency. amys. Aftur fyftene dawes, pat he hadde y ordeyned pis R. Brunne, p. 164. Every people, nation, and language, which speak any thing amiss against the God of Shadrach, Meshach, and Abednego, shall be cut in pieces, and their houses shall be made a dunghill; because there is no other God that can deliver after this sort. Daniel, iii. 29. We hope therefore to reform ourselves, if at any time we have done amiss, is not to sever ourselves from the church we were of before. Hooker. O ye powers that search The heart of man, and weigh his inmost thoughts, If I have done amiss, impute it not! Addison. Your kindred is not much amiss, 'tis true; Yet I am somewhat better born than you. Dryden. I built a wall, and when the masons played the Inaves, nothing delighted me so much as to stand by, while my servants threw down what was amiss. Swift, AMISUS, the chief city of the ancient kingdom of Pontus, built by the Milesians, and peopled partly by them, and partly by a colony from Athens. It was at first a free city, like the other Greek cities in Asia; but afterwards subdued by Pharnaces king of Pontus, who made it his metropolis. It was taken by Lucullus at Eupatoria a neighbouring city, in the Mithridatic war. Several medals of Adrian, Sabina, Ælius Cæsar, Antoninus Pius, &c. were struck here. Some of the inscriptions show its alliance with the town of Amastris, as does a medal of which the annexed is a diagram, representing two Amazons standing by an altar with their right hands Joined, one bearing an axe, and the other a spear; to denote MICOC that these two towns, which deduced their origin from the two Amazons, Amisus and Amastrus, entered into alliance with each other. AMIT', A, mitto, to let out, let go. To AMISSION, send away, to lose. Obsolete. But ice is water congealed by frigidity of the air whereby it acquireth no new form, but rather a consistence or determination of its diffluency, and amitteth not its essence, but condition of fluidity. Brown's Vulgar Errours. If any shall further queery why magneticall philosophy excludeth decussations, and needles transversly placed do naturally distract their verticities? why geomancers do imitate the quintuple figure in their mother's characters of acquisition and amission, &c. He shall not fall on trite or trivial disquisitions. Brown's Garden of Cyrus. AMITERNUM, a town of the Sabines, in Italy, now extinct. The ruins are to be seen on the level ridge of a mountain, near S. Vittorino, not far from Aquila, which rose out of the ruins of Amiternum. AMITTERE LEGEM TERRE, among lawyers, a disablity to appear as witness in any court. Such was the punishment of a champion overcome or yielding in battle, of jurors found guilty in a writ of attaint, of a person outlawed, &c. AMITY. Fr. amitié; from amo. Friendly intercourse between nations; opposed to a state of warfare: denoting also agreement, and absence of discord among lesser bodies of people, and friendship between individuals. For excellent and wonderful art thou (O Lord) and thy face is full of amyte. Bible,1539, Ester. ch. xv. Debateful strife, and cruell enmity, The famous name of knighthood fowly shend; But lovely peace, and gentle amity, And in amours the passing howres to spend, The mightie martiall handes doe most commende. Spenser's Faerie Queene, b. ii. c. 6. LAF. I have then sinned against his experience, and transgressed against his valour, and my state that way is dangerous, since I cannot yet find in my heart to repent. Here he comes, I pray you make us friends, I will pursue the amity. Shakspeare's All's Well that ends Well. Nothing is so strong a tie of amity between nation and nation as correspondence in laws, customs, manBurke. ners, and habits of life. AM-KAS, in history, a spacious saloon in the palace of the Great Mogul, where he gave audience to his subjects, and appeared on solemn festivals with extraordinary magnificence. AMLI, one of the Aleutian islands in the North Pacific Ocean, forty-four miles in length. AMLIAK, another of the Aleutian islands. Long. 187° 14′ E., lat. 53° 30′ N. AMLWCH, a town of North Wales, on the north side of the isle of Anglesey, eighteen miles from Holyhead, and 261 north-west of London. Since the discovery of copper mines in this neighbourhood, the town of Amlwch, or Anlwick has risen into considerable importance. The harbour was made at the expense of the Parys Mine Company, and cut out of the solid rock. It is capable of admitting thirty vessels of two hundred tons burden each. The mines are about two miles from the town. Here is an elegant modern church, consecrated by the late bishop of Bangor in 1801, and said to have been erected at the expense of £4,000, the whole of which was defrayed by the Mine Company. Population 4629. It has an annual fair on the 12th of November. AMMA, among ecclesiastical writers, a term used to denote an abbess or spiritual mother. AMMA, in authors of the middle age, a spiritual mother; an abbess or superior of a nunnery. AMMAILARE, in old records, to enamel. AMMAN (John Conrad), a native of Schaffhausen, was born in 1669, and distinguished himself by his success in teaching the deaf and dumb to speak. He published Surdus Loquens, 8vo. Haerlem, 1692, and De Loquela, 12mo. Amsterdam, 1700: also an edition of Cœlius Aurelianus, in quarto 1709; and died in 1724 at Marmund in the Netherlands. AMMAN (John), son of the above, was fellow of the Royal Society in London, and member of the Academy of Sciences at Petersburgh. He published Stirpium rariorum in imperio Rutheno Sponte Provenientium icones et Descriptiones, in 4to. and died in 1740. AMMAN (Paul), was a native of Breslaw, who settled in 1674 at Leipsic, where he gave lectures on physiology, history, and botany. He is the author of Character naturalis Plantarum. Irenicum Numa Pompilii cum Hippocrate, 8vo. Parænesis ad discentes occupata circa Institutionum Medicarum emendationem, in duodecimo. Archeas Syncopticus, Eccardi Leichneri. And died in 1691. AMMANIA, in botany, a genus of plants of the monogynia order, belonging to the tetandria class, in the natural method ranking under the seventeenth order, Calycanthemæ. The characters are: CAL. an oblong, erect, bellshaped perianthium, with eight striæ, quadrangulated, octodented, and persistent: COR. is either wanting or consists of four ovate expanding petals inserted in the calyx: STAM. four bristly filaments the length of the calyx; the antheræ are didymous: PIST. a large ovate germen, above; the stylus simple and very short; the stigma headed: PER. a roundish four-celled capsule, covered by the calyx: the seeds are numerous and small. Of this genus there are three species enumerated; all of them natives of warm climates. AMMER, in geography, a powerful but infamous tribe of Arabs, who, according to Dr. Shaw, inhabit the province of Constantina, in Africa; and, contrary to the practice of their brethren, prostitute their wives and daughters. Also a range of mountains in the above neighbourhood. AMMER, a small lake of Bavaria, near the foot of the Alps, about half way between the Iser and the Lech. AMMERLAND, a market town with two castles in Upper Bavaria, circle of the Iser, district of Wolfrathshausen, near the lake of Wurm. AMMERPOOR, or ANEAPURAS, a town of Hindostan, on the north-west of the Bagmutty river, in the district of Mocwanpoor, ten miles east of the last place, and in N. lat. 27° 31′, E. long. 82° 26'. AMMERSEE, a lake of Upper Bavaria, in the circle of the Iser. It is nine miles long, four and a half broad, and very abundant in fish. There is AMMI, BISHOP'S WEED, in botany, a genus of the digynia order, belonging to the pentandria class of plants; and ranking in the natural method under the forty-fifth order, umbellatæ. The characters are: CAL. the universal umbel manifold; the partial one short and crowded; the involucra pinnatifid, with numerous leaflets : COR. radiated, and all hermaphrodite: STAM. five capillary filaments; the antheræ roundish: PIST. a germen beneath: the STYLI two and reflected; and the stigmata obtuse. no pericarpium; the fruit roundish, polished, striated, small and partible. The seeds are two, plane-convex, and striated. Of this there are three species: 1. A. Copticum, or Egyptian bishop's weed, now no otherwise known than by the figure of its seeds, which were formerly used in medicine. 2. A. glaucifolium, with all its leaves cut in the form of a spear, is perennial, and very hardy. 3. A. majus, or common bishop's weed, the seeds of which are used in medicine, an annual plant. AMMI is also a name of the sison ammi, the cicuta bulfera, the seseli ammoides, and sium falcaria of Linnæus. He AMMIANUS (Marcellinus), a Grecian and a soldier, as he calls himself, was born at Antioch, and flourished under Constantius and the succeeding emperors, as late as Theodosius. served under Julian in the east; and wrote in Latin an interesting history, from the reign of Nerva to the death of Valens, in thirty-one books; of which only eighteen remain. Though a pagan, he speaks with candour and moderation of the Christian religion, and even praises it: his hero is the emperor Julian. He died about A. D. 390. The best edition of his history is that of Gronovius, in 1693. AMMINEA UVA, in botany, the grapes of a wild vine, common in the hedges of Italy, and other places. AMMION, in chemistry, cinnabaris. AMMIRATO (Scipio), an eminent Italian historian, born at Lecce in Naples, in 1531. After travelling over a great part of Italy, he was engaged by the grand duke of Tuscany, to write the history of Florence: for which he was presented to a canonry in the cathedral there. His works while in this station are, 1. Arguments, in Italian verse, 4to. Venice, 1548. 2. Il Decalione Dialogo del Poeta, 8vo. Naples, 1560. 3. Istorie Fiorentine, dopo la Fondatione di Fierenze insino all, anno 1574. He died in 1601. AMMITES, in mineralogy, a kind of figured stone of a loose open contexture, formed of a number of small globular stones. It is found in different parts of Germany, of various colours and degrees of hardness. It is by some reckoned the same with the ammodytes. AMMOCITUS, in ichthyology, the sand-eel. See AMMODYTES. AMMOCHOSIA, from aμμoç, sand, and yɛw, to lie along, a remedy prescribed by ancient physicians, which consisted in laying the patient on warm sand, and covering him with it. AMMOCHRYSOS, from appoç, sand, and Xprooc. gold, a stone very common in Germany, and seeming to be composed of a golden sand. It is of a yellow gold-like colour, and its particles are very glossy, being all fragments of a coloured talc. It is usually so soft as to be easily rubbed to a powder in the hand; but sometimes requires grinding to powder in a mortar, or otherwise. It is used as sand to strew over writing. There is another kind of it less common, but much more beautiful, consisting of the same sort of glossy spangles, not of a gold colour, but a bright red, like vermilion. AMMOCHYSUS, in natural history, a kind of gem supposed to be the same with the avanturine. AMMODYTES, from aupos, sand, and durns, a diver: sand eel, in ichthyology, a genus of fishes, belonging to the order of apodes. This fish resembles an eel, and seldom exceeds a foot in length. The head is compressed, and narrower than the body; the upper jaw larger than the under; the body cylindrical, with scales hardly perceptible. There is but one species, viz.: Ammodytes tobianus, or the launce, a native of Europe. AMMODYTES, in zoology, a species of serpent, by some called serpens cornutus, from a protuberance on its head. It is yellow or sand coloured, and about the size of a viper; its jaws are wide, and the upper part of the head has a wart-like excrescence, resembling a horn. It is principally found in Lybia and some parts of Illyria. AMMOIDES, in botany, the name given by Boerhaave, to the bishop's weed. See AMMI. AMMON, an ancient city of Marmarica, in which stood the temple of Jupiter Ammon, round which there was nothing but sandy wastes. Pliny says, that the oracle of Ammon was twelve days' journey from Memphis, and among the Nomi of Egypt he reckons the Nomos Ammoniacus: Diodorus Siculus, says, the district where the temple stood, though surrounded with desarts, was watered by dews which fell nowhere else in all that country. It was agreeably adorned with fruitful trees and springs, and full of villages. In the middle stood the acropolis or citadel, encompassed with a triple wall; the first and inmost of which contained the palace; the others the apartments of the women, the relations and children, as also the temple of the god, and the sacred fountain. Without the acropolis, at no great distance, was another temple of Ammon, shaded by a number of tall trees; near which there was a fountain, called Solis Fons, or the fountain of the sun, because subject to extraordinary changes according to the time of the day; being at morning and evening warm, at noon cold, and at midnight extremely hot. A kind of fossil salt was said to be naturally produced here. It was dug out of the earth in large oblong pieces, sometimes three fingers in length, and transparent as crystal. It was thought a present worthy of kings, and used by the Egyptians in their sacrifices. From this our sal ammoniac has taken its name. AMMON, R, Heb. i. e. the son of my people, or Ben-Ammi, the son of Lot, by his youngest daughter. He was the father of the Ammonites, and dwelt to the east of the Dead Sea, in the mountains of Gilead. See AMMONITES. AMMON, OF HAMMON, in heathen mythology, the name of the Egyptian Jupiter, worshipped under the figure of a ram. The fable is, that Bacchus having subdued Asia, and passing with his army through the desarts of Africa, was in great want of water: but Jupiter his father, assuming the shape of a ram, led him to a fountain, where he refreshed himself and his army; in gratitude for which Bacchus built there a temple to Jupiter, under the title of Ammon, from the Greek appog; and alluding to the sandy desart where it was built. AMMONIA. This name has been given to a material which has actually been classed among the alkalies, in consequence of the properties it possesses, in common with these last, of uniting with acids to form neutral compounds, of converting vegetable blues to green, and yellows to red: it is moreover attracted to the negative pole of a voltaic battery as are the other alkalies; and hence its alkaline nature being considered as demonstrated, it has been termed volatile alkali, this last name and ammonia being employed as synonymous. This material (ammonia) when pure exists in a gaseous condition, and it does not become liquid, according to Guyton, till the temperature to which it is exposed be reduced to 56° of Fahrenheit; and even then its liquefaction is attributable, according to the opinion of other chemists, to the hygrometric vapour it contains, and from which the pure gas is separated with extreme difficulty. The specific gravity of ammonia, at 60° Fahrenheit, is stated to be 0,000,715, being to that of atmospheric air as 590 to 1000; 100 cubic inches of it weigh, according to Kirwan 18.2; according to Davy 18.4; and according to Biot, and Arago 19.6 grains. Its smell is extremely pungent; it inflames the skin, and animals are immediately killed by immersion in it. Its constituents are hydrogen and nitrogen, the former principle being in very large proportion to the latter; it appears probable (says Mr. Brande), that one volume of ammonia is resolved by electric decomposition into two volumes of a mixture of hydrogen and nitrogen, consisting of three volumes of hydrogen and one volume of nitrogen; and Dr. Prout, in the 38th number of the Annals of Philosophy, gives the theoretical proportions of three atoms of hydrogen + one azote (nitrogen). Its composition, however, was not discovered by its synthetic formation; for when hydrogen and nitrogen are mixed together in a gaseous state, the elasticity of each gas is an obstacle to their mutual affinity; nor can their combination be effected, as is the case with some other mixed gases, by transmitting the electric spark through the mixture, or exposing them to a high temperature. It may be, and very generally is, obtained by heating a mixture of quick-lime and sal ammoniac (muriate of ammonia). Two parts of the former, and one of the latter are to be introduced into a small glass retort; and upon the application to this mixture of a gentle heat, the gas passes over, which must be collected over mer cury. It is also produced by more indirect processes, as from the decomposition of animal matter by heat. Bones exposed to a high temperature give out ammonia, from the combination of portions of the hydrogen and nitrogen of the animal matter contained in them. Other animal substances in decomposition form also ammonia; as do, indeed, some varieties of vegetable matter. Coal soot, for instance, which is of vegetable origin, yields it in combination with some of the acids. But when the material in question is obtained by these processes, it is mixed with an empyreumatic oil, which gives it a fœtid odour; thus, what is usually called the spirit of hartshorn, from its having been obtained in abundance from the horns of the hart, is only different from liquid ammonia by the latter being without and the former combined with this empyreumatic oil. See AMMONIAC SAL (Sal Ammoniac, or muriate of Ammonia). Ammonia is inflammable, and by this property is it said to be distinguished from all other substances possessed of alkaline properties. When a kindled match is immersed in it, the flame, before it is extinguished, is enlarged, and is of a pale yellow colour at the edges; if mixed previously with two-thirds of atmospheric air it kindles, and gives a white lambent flame. It detonates with oxygen gas; this detonation is effected only when the two gases are in a certain proportion. With a greater proportion of oxygen gas to ammonia than that of three to one, or of ammonia to oxygen than that of three to 1.4, the mixture does not inflame. But within these limits it is inflamed readily by the electric spark. The results are different according to the proportion. If the volume of oxygen gas be double that of the ammonia, the latter is entirely consumed; its hydrogen combines with the requisite quantity of oxygen, forming water, and its nitrogen partly remains with any redundant oxygen, and is partly combined with a portion of oxygen forming nitric acid, which uniting with ammonia forms a dense vapour. If the ammonia exceeds considerably the oxygen, no nitric acid is formed; if the proportion of oxygen is that which is just necessary to saturate the hydrogen, nitrogen remains: but if the proportion be even lower than this, still the whole of the ammonia is decomposed; part of its hydrogen combines with the oxygen, and the remaining hydrogen, with the nitrogen, form a mixture which, on the addition of a fresh quantity of oxygen, may be inflamed by the electric spark. No mixture of ammonia, in any proportion, with atmospheric air can be inflamed by the electric spark; but the mixture of it with oxygen, even when diluted with six times its bulk of atmospheric air, burns. Ammonia introduced from a small aperture in a tube into oxygen gas suffers slow combustion, burning with a pale yellow flame. Nitrous oxide, and nitric oxide gases form mixtures with ammonia which are capable of being inflamed. Murray. Although, as we have said, ammonia, when pure, exists naturally in a gaseous condition, it must be observed that water, at the temperature of 50°, takes up 670 times the volume of the material; and the usual state in which it is em ployed, as well in chemistry as in medicine, is in solution; this solution in the London Pharmacopoeia bears the name of liquor ammoniæ, and may be obtained by passing the gas into water in a proper apparatus, or by distilling over the water and gas together. Mr. R. Phillips, in his remarks on the London Pharmacopoeia, recommends the following process for obtaining this liquid ammonia, which Mr. Brande, in his valuable work entitled A Manual of Chemistry, quotes and approves. On nine ounces of well-burned lime pour half a pint of water; and, when it has remained in a well-closed vessel for about an hour, add twelve ounces of muriate of ammonia in powder, and three pints and a half of boiling water; when the mixture has cooled, pour off the clear portion, and distil, from a retort, twenty fluid ounces. The specific gravity of this solution, which is sufficiently strong for most purposes, is 0.954. It should be preserved in well-stopped glass bottles, since it loses ammonia when exposed to the air, and absorbs carbonic acid. The first clue to the discovery of the properties by which ammonia is characterised, was given by Dr. Priestley. He first produced an alkaline air by a mixture of lime and sal ammoniac, which was absorbed by water, forming ' volatile spirit of sal ammoniac, much stronger than that produced by other means;' he observed, also, that on taking the electric spark or explosion in this air over quicksilver, its volume is enlarged, until it occupies three times its original space; and that its properties also, as well as its volume, are changed, no longer being absorbed by water, and becoming moreover inflammable. Dr. Priestley afterwards found, that by heating certain metallic oxides in this air, they were reduced to the metallic state, water being developed, and the residual air being apparently nitrogen gas. The theory (says Murray) of these experiments, is now sufficiently evident. By the action of the electric spark, or of a red heat, the gas is resolved into its constituent elements, hydrogen and nitrogen; hence the enlargement of volume and change of properties. The reduction of the metallic oxides is owing to the oxygen of the oxide combining with the hydrogen of the ammonia, and forming a small portion of water, the metal of course appearing in its metallic state; while the nitrogen, the other component principle of the alkali, being freed from its state of combination, assumes the gaseous form. : After the splendid discoveries respecting the composition of alkalies (see ALKALI), it was conceived that ammonia would prove to contain oxygen; but hitherto experiment has failed in showing this to be the case, although weight has been supposed due to the inference from analogy and on this supposition, says a modern chemist, it must be inferred that either hydrogen or nitrogen must be a compound, and contain oxygen as a constituent element. Assuming, likewise, from analogy the metallic base of ammonia, and proceeding on the principle of Richter, that all metallic bases saturating the same quantity of an acid must contain the same portion of oxygen combined with them; the proportion of oxygen in ammonia must be 47 in 100 parts, according to Berzelius, who considers the nitrogen as the furnisher of it. Berzelius adds some other arguments of an analogical nature to strengthen the inference of oxygen being contained in ammonia; which has also been supposed, from analogy with the other alkalies, to have a metallic base; but we want experiments from which to predicate either that oxygen is a constituent of this substance, or that it contains metallic matter; although the ammoniacal hydrurets of mercury and potassium, obtained by subjecting quicksilver and potassium mixed with liquid ammonia to voltaic agency, present results which are exceedingly interesting in re'ference to the analogy between ammonia and other alkalies. In the article chemistry, and in alphabetical order, we shall treat of the several substances which enter into combination with ammonia to form distinct compounds; but we deem it expedient to attach to this paper a particular account of sal ammoniac, on account of this substance being the material from which ammonia may be more directly produced, because this substance is used in the arts for a variety of purposes, especially in certain metallurgic operations, and because it constitutes an extensive manufacture. We cannot better accomplish this purpose (which falls indeed into our alphabetical arrangement), than by extracting, verbatim, the account given by Dr. Ure of this material in the Dictionary of Chemistry lately published by that highly meritorious author. AMMONIAC SAL (SAL AMMONIAC), MURIATE OF AMMONIA. This salt was originally fabricated in Egypt. The dung of camels and other animals constitutes the chief fuel used in that country. The soot is carefully collected; globular glass vessels, about a foot in diameter, are filled within a few inches of their mouth with it, and are then arranged in an oblong furnace, where they are exposed to a heat gradually increased. The upper part of the glass balloon stands out of the furnace, and is kept relatively cool by the air. On the third day the operation is completed, at which time they plunge an iron rod occasionally into the mouths of the globes to prevent them from closing up, and thus endanger the bursting of the glass. The fire is allowed to go out; and, on breaking the cooled globes, their upper part is found to be lined with sal ammoniac in hemispherical lumps about two inches and a half thick, of a grayish white colour, semi-transparent, and possessed of a degree of elasticity; twenty-six pounds of soot yield six of sal ammoniac. The ordinary mode of manufacturing sal ammoniac in Europe, is by combining with muriatic acid the ammonia resulting from the igneous decomposition of animal matters in close vessels. Cylinders of cast iron are charged with bones, horns, parings of hides, and other animal matters; and being exposed to a full red heat, an immense quantity of an impure liquid carbonate of ammonia distils over. Mr. Minish contrived a cheap method of converting this liquid into sal ammoniac: he digested it with pulverised gypsum, or simply made it percolate through a stratum of bruised gypsum; whence resulted a liquid sulphate of ammonia, and an insoluble carbonate of lime. The liquid evaporated to dryness was mixed with muriate of soda, put into large glass balloons, and decomposed by a subliming heat. Sal ammoniac was found above in its characteristic cake, with sulphate of soda remaining below. M. Leblanc, of St. Denis near Paris, invented another method of much ingenuity, which is described by a commission of French chemists in the 19th volume of the Annales de Chimie, and in the Journal de Physique, for the year 1794; he used tight brick-kilns instead of iron cylinders, for holding the materials to be decomposed. Into one he put a mixture of common salt and oil of vitriol; into another animal matter. Heat extricated from the first muriatic acid gas, and from the second ammonia; which bodies being conducted by their respective flues into a third chamber lined with lead, and containing a stratum of water on its bottom, entered into combination, and precipitated in solid sal ammoniac on the roof and sides, or liquid at the bottom. In the 20th volume of the Annales a plan for employing bittern or muriate of magnesia to furnish the acid ingredient is described. An ingenious process on the same principles was some time ago commenced at Borrowstounness in Scotland, by Mr. Astley. He imbued in a stove-room, heated by brick flues, parings of skins, horns, and other animal matters, with the muriate of magnesia, or mother water of the sea salt works. The matters thus impregnated and dried, were subjected in a close kiln to a red heat, when the sal ammoniac vapour sublimed, and was conducted either in a solid form into an adjoining chamber or chimney, or else into a stratum of water on its bottom. Muriate of magnesia at a red heat evolves muriatic acid gas; an evolution probably aided in the present case by the affinity of ammonia. From coal soot likewise a considerable quantity of ammonia in the state of carbonate and sulphate may be obtained, either by sublimation or lixiviation with water. These ammoniacal products can afterwards be readily converted into the muriate as above described. M. Leblanc used a kettle or eolipile for projecting steam into the leaden chamber to promote the combination. It is evident that the exact neutralization essential to sal ammoniac might not be hit at first in these operations; but it could be afterwards effected by the separate addition of a portion of alkaline or acid gas. As the mother waters of the Cheshire salt-works contain only 3 per cent. of muriate of magnesia, they are not suitable like those of sea-salt works for the above manufacture. For the medicinal properties of sal ammoniac, see MATERIA MEDICA and MEDICINE. AMMONIAC, GUM. This is a gum resin which consists, according to Braconnot, of 70 resin, 18.4 gum, 4.4 glutinous matter, 6 water, and 1.2 loss, in 100 parts. It forms a milky solution with water; is particularly soluble in alcohol, and entirely so in æther, nitric acid, and alkalies. Specific gravity, 1.200. See MATERIA MEDICA and MEDICINE. |