SAL AMMONIAC ,' or AMMONIUM CHLORIDE, NH4C1, the earliest known
See also:salt of
See also:ammonia (q.v.), was formerly much used in dyeing and metallurgic operations . The name Hammoniacus sal occurs in Pliny (Nat . Hist. xxxi . 39), who relates that it was applied to a kind of fossil salt found below the sand, in a
See also:district of
See also:Cyrenaica . The general opinion is, that the sal ammoniac of the ancients was the same as that of the moderns; but the imperfect description of Pliny is far from being conclusive . The native sal ammoniac of Bucharia, described by
See also:Model and Karsten, and analysed by M . H . Klaproth, has no resemblance to the salt described by Pliny . The same remark applies to the sal ammoniac of volcanoes . Dioscorides (v . 126), in mentioning sal ammoniac, makes use of a phrase quite irreconcilable with the description of Pliny, and rather applicable to
See also:rock-salt than to our sal ammoniac . Sal ammoniac, he says, is peculiarly prized if it can be easily split into rectangular fragments .
Finally, we have no
See also:proof whatever that sal ammoniac occurs at
See also:present, either near the
See also:temple of
See also:Jupiter Ammon, or in any
See also:part of Cyrenaica . Hence we conclude that the
See also:term sal ammoniac was applied as indefinitely by the ancients as most of their other chemical terms . It may have been given to the same salt which is known to the_ moderns by that appellation, but was not confined to it . In any case there can be no doubt that it was well known to the alchemists as early as the 13th century . Albertus
See also:Magnus, in his
See also:treatise De alchymia, informs us that there were two kinds of sal ammoniac, a natural and an artificial . The natural was sometimes
See also:white, and sometimes red; the artificial was more useful to the chemist . He does not tell us how it was prepared, but he describes the method of subliming it, which can leave no doubt that it was real sal ammoniac . In the
See also:Opera mineralia of Isaac Hollandus the elder, there is likewise a description of the mode of subliming sal ammoniac .
See also:Valentine, in his Currus triumphalis antimonii, describes some of the
See also:peculiar properties of sal ammoniac in, if possible, a still less equivocal manner .
See also:Egypt is the
See also:country where sal ammoniac was first manufactured, and from which
See also:Europe for many years was supplied with it . This commerce was first carried on by the Venetians, and afterwards by the Dutch . Nothing was known about the method employed by the Egyptians till the
See also:year 1719 .
In 1716 C . J .Geoffroy read a paper to the French Academy, showing that sal ammoniac must be formed by sublimation; but his opinion was opposed so violently by W . Homberg and N .
See also:Lemery, that the paper was not printed . In 1719 D . Lemaire, the French
See also:consul at Cairo, sent the Academy an account of the mode of manufacturing sal ammoniac in Egypt . The salt, it appeared, was obtained by
See also:simple sublimation from soot . In the year 176o
See also:Linnaeus communicated to the Royal Society a correct detail of the whole
See also:process, which he had received from Dr F .
See also:Hasselquist, who had travelled in that country as a ' Some derive the name sal ammoniac from Jupiter Ammon, near whose temple it is alleged to have been found; others, from a district of Cyrenaica called Ammonia . Pliny's derivation is from the sand (4taµos) in which it occurred.naturalist (Phil . Trans., 176o, p .
504) . The dung ofblack
See also:cattle, horses,
See also:sheep, goats, &c., which contains sal ammoniac ready formed, is collected during the first four months of the year, when the animals feed on the
See also:spring grass, a kind of
See also:clover . It is dried, and sold to the
See also:people as fuel . The soot from this fuel is carefully collected and sold to the sal ammoniac makers, who
See also:work only during the months of
See also:March and
See also:April, for it is only at that
See also:season of the year that the dung is
See also:fit for their purpose . - The composition of this salt seems to have been first discovered by J . P . Tournefort in 1700 . The experiments of C . J . Geoffroy in 1716 and 1723 were still more decisive, and those of H . L .
See also:Duhamel de Monceau, in 1735,
See also:left no doubt upon the subject .
See also:Thomson first pointed out a process by synthesis, which has the
See also:advantage of being very simple, and at the same
See also:time rigidly accurate, resulting from his observation that when hydrochloric acid
See also:gas and ammonia gas are brought in contact with each other, they always combine in equal volumes . The first attempt to manufacture sal ammoniac in Europe was made, about the beginning of the 18th century, by Mr
See also:Goodwin, a chemist of
See also:London, who appears to have used the
See also:mother ley of common salt and putrid urine as ingredients . The first successful manufacture of sal ammoniac in
See also:Great Britain was established in
See also:Edinburgh about the year 176o . It was first manufactured in France about the same time by A .
See also:Baume . Manufactories of it were afterwards established in Germany,
See also:Holland and
See also:Flanders . - It is now obtained from the ammoniacal liquor of gas
See also:works by distilling the liquor with milk of lime and passing the ammonia so obtained into hydrochloric acid . The solution of ammonium chloride so obtained is evaporated and the crude ammonium chloride purified by sublimation . The subliming apparatus consists of two parts: (1) a hemispherical stoneware
See also:basin placed within a close-fitting iron one, or an enamelled iron basin, and (2) a hemispherical lead or stoneware lid, or dome, cemented on the top of the basin to prevent leakage . The dome has a small aperture in the top which remains open to preclude accumulation of pressure . The carefully dried crystallized salt is pressed into the basin, and, after the has been fitted on, is exposed to a long-lasting moderate
See also:heat . The salt volatilizes (mostly in the
See also:form of a mixed vapour of the two components, which reunite on cooling), and condenses in the dome in the form of a characteristically fibrous and tough crust .
The pure salt has a
See also:sharp saline taste and is readily soluble in
See also:water . It readily volatilizes, and if moisture be rigorously excluded, it does not dissociate, but in the presence of mere traces of water it dissociates into ammonia and hydrochloric acid (H . B .
See also:Baker, Journ . Chem .
See also:Soc., 1895, 65, p . 612) . Sal ammoniac (ammonium chloride,
See also:British and
See also:United States pharmacopoeiae) as used in
See also:medicine is a white crystalline odourless powder having a saline taste . It is soluble in i in 3 of
See also:cold water and in I in 50 of 90 %
See also:alcohol . It is incompatible with
See also:carbonates of the alkalis . The dose is 5 to 20 grs . Ammonium chloride has a different
See also:action and therapeutic use from the
See also:rest of the ammonium salts .
It possesses only slightinfluence over the heart and respiration, but it has a specific effect on mucous membranes as the elimination of the
See also:drug takes place largely through the lungs, where it
See also:aids in loosening bronchial secretions . This action renders it of the utmost value in
See also:bronchitis and
See also:pneumonia with associated bronchitis . The drug may be given in a mixture with glycerine or
See also:liquorice to cover the disagreeable taste or it may be used in a spray by means of an atomizer . The inhalation of the fumes of nascent ammonium chloride by filling the
See also:room with the gas has been recommended in foetid bronchitis . Though ammonium chloride has certain irritant properties which may disorder the stomach, yet if its mucous membrane be depressed and atonic the drug may improve its
See also:condition, and it has been used with success in gastric and intestinal catarrhs of a subacute type and is given in doses of to grains
See also:half an
See also:hour before meals in painful dyspepsia due to hyperacidity . It is also an intestinal and hepatic stimulant and a feeble diuretic and diaphoretic, and has been considered a specific in some forms of neuralgia .
GEORGE AUGUSTUS HENRY SALA (1828-1895)
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