C H E M 
Mr. Demachy.fir.ft obferved this decompofiticn. MefTrs. 
Spielman and Corvinus have likewife bufied themfelves 
on this fubjeft; but Berthollet has made experiments 
which are frill more accurate than thofe which preceded 
him. He has obferved, that two ounces of the tartare- 
ous acidule required eighteen months for their entire 
decompoiition; that it afforded fix and a half drachms 
of carbonat of potafli, itill oily, and mixed with a fmall 
quantity of carbon ; that this quantity of alkali answer¬ 
ed with fufiicient exaftnefs to that which was afforded 
by the acidule by combuftion and calcination. The al¬ 
kaline refidue of the diftillation, and this fpontaneous 
decompofition, prove, therefore, that the tartareous aci- 
dule contains nearly one fourth of its weight of p'otafli. 
None of the combuftible bodies have any aftion upon 
tartareous acidule. Some metals, in the oxyd Hate, 
unite to it with excefs of acid, forming triple falts. 
The combination of tartareous acidule and antimony, 
is called Jlibiated, or emetic , or antimoniated, tartar : it is 
the tartarit of antimony and of potafli. As it is one of 
the moft important remedies afforded by chemiftry, it is 
neceffary to examine its properties with thegreateft care. 
Since the time of Adrian de Mynficht, who fil'd defended 
this compofition, in the year 1631, the procefs for making 
it has been greatly varied. The Pharmacopoeia, and the 
writings of chemifts, all differ in the antimonial fub- 
ftances directed to be employed, as well as in the tarta¬ 
reous acidule and water, either with refpect to quantity, 
or the method of applying them to each other. The 
fublimated white, the brown vitreous, or orange, oxyds, 
have been fucceflively preferibed : fome direil thefe Jub¬ 
ilances to be boiled with tartareous acidule, and a greater 
or lefs quantity of water, for ten or twelve hours ; others 
dire ft the ebullition to be continued no longer than half 
an hour j others again require the filtered lixivium to 
be evaporated to drynefs ; and laftly, there are others 
who direft it to be cryftallized, and the cryltals only to 
be ufed in medicine. Hence it happens, that tartarit of 
antimony is never the fame fubftance, but pofiefies vari¬ 
ous degrees of force, fo that its effefts cannot be clearly 
afeertained. Vitreous oxyd of antimony has been chofen 
in preference to other antimonial fubftances, becaufe it 
is one of the moft foluble by the acidule of tartar; but 
this metallic glai's may be more 01 lefs oxydated, and 
the different degrees of oxydation muft affeft its emetic 
power. However, if very tranfparent vitreous oxyd of 
antimony, previoufly well levigated, be boiled in water, 
with an equal weight of tartareous acidule, till the lat¬ 
ter is faturated, and this folution be filtered and evapo¬ 
rated by a gentle heat, cryftals of antimonial tartarit are 
obtained, by Handing, wliofe emetic power appears to 
be lufficiently conftant. The liquor being decanted and 
evaporated, affords new cryftals for feveral fucceffive 
times. The mother water contains fulphur, tartarit of 
potafli, and a certain quantity of antimoniated alkaline 
fulpliure. When the mixture of tartareous acidule, vi¬ 
treous oxyd of antimony, and water, has been boiled for 
the preparation of antimoniated tartarit, and paffed 
through the filtre, a yellow or brown gelatinous fub¬ 
ftance remains behind, which Rouelie has examined. 
According to Prouft, this jelly affords, by diftillation, a 
very inflammable pyrophorus. 
Macquer propofes to fubftitute the white oxyd, preci¬ 
pitated from muriat of antimony by water, in the place 
of vitreous oxyd of antimony, in the preparation of 
emetic tartar. This oxyd is itfelf a violent emetic, 
which Macquer confidered as always the fame. Berg¬ 
man has adopted the opinion of Macquer ; and nee that 
time, a tartarit of antimony has been prepared in the la¬ 
boratory of the academy of Dijon according to the me¬ 
thod of Bergman and De Laffone. This medicine has 
been ufed with the greateft fuccefs: it operates, in a 
dofe of three grains, without fatiguing the ftomach and 
jnteftines. 
Lartigue, an apothecary at Bourdeaux, has lately pro- 
[ S T R Y. 327 
pofed another method: Mix twelve parts of the white 
oxyd of antimony with fifteen of the acidulated tartarit 
of potafli reduced to powder and drained through fiik. 
Throw the mixture by degrees into hot water, and boil 
it till the acidule is faturated, or till the acid tafte of tbs 
liquor changes to fweet, which will be in about a quar¬ 
ter of an hour; filtre the liquor, and by reft and cooling 
it will furnifh very white cryftals, compofed of trihedral 
pyramids. 
The antimoniated tartarit of potafli is decompofable 
by heat, which converts it to a coaly fubftance. It efflo- 
refees in the air, and becomes a white farinaceous pow¬ 
der; it is foluble in fixly parts of cold water, or in a 
much lefs quantity of hot water. It cryftallizes by cool- 
ling; and is decompofed by lime and alkalis. Calcare¬ 
ous earth, bark, and pure water, in a large dofe, are ca¬ 
pable of decompofing it; whence it follows, that it 
ought to be adminiftered only in diftilled water. Al¬ 
kaline fulphures, and fulphurated hydrogen gas, preci¬ 
pitate from it a red powder, or kind of fulphurated oxyd 
of antimony, which may ferve as a teft for the pre¬ 
fence of this fait in all liquors containing it. Iron 
feizes the acid of tartar, and feparates the oxyd of an¬ 
timony ; antimoniated tartar ought not, therefore, to 
be prepared in veflels of this metal. Durande, phyiician 
and profefTor at Dijon, propoies that this medicine be 
made publicly, and by one uniform-procefs,’eftablifhed 
by law, as the theriaca is made ; and we are convinced, 
that the greateft advantages would arife to the praftice 
of phyfic from fucli a regulation being adopted. 
Tartareous acidule has a fenfible aftion on the oxyds 
of lead. Rouelie the younger has afeertained, that the 
tartarit of,lead, produced in this operation, does not 
remain difi'olved, but that the liquor, by evaporation, 
affords pure tartarit of potafli, which was 1 ready formed 
in the tartareous acidule. This is one of the proceffes 
he has made ufe of to prove, that potafli exiils in tartar. 
Copper, and its oxyds, are readily attacked by the tar¬ 
tareous acidule: the refult is a felt, of a beautiful green, 
capable of cryftailization, but hitherto little examined. 
Iron is very Itrongly afted on by tartareous acidule; 
and its different combinations form feveral compofi- 
tions much ufed in medicine. The firfi, called chaiy- 
beated tartar , is prepared, by boiling four ounces of le¬ 
vigated iron filings with one pound of white tartar, in 
twelve pounds of water. When the tartar is diflolyed, 
the liquor is filtered, and depolites cryftals, more of 
which may be obtained by fubfequent evaporation. 
To prepare the tartarized tindiure of Mars, a pafte is 
made, with fix ounces of iron filings, one pound of white 
tartar in powder, and a fufiicient quantity of water. This 
mixture is left at reft for twenty-four hours ; after which 
twelve pounds of water are added, and the whole boil¬ 
ed for two hours; frefli water being added in propor¬ 
tion as the evaporation goes forward. The liquor is 
then decanted, filtered, and thickened, by boiling to 
the confillence of fyrup; after which one ounce of ipirit 
of wine is added. Rouelie afeertained, that potafhexifts 
at liberty in this tinfture, and that by treating it with 
acids, neutral felts, with bafe of this alkali, are obtained. 
Ludovicus’s tinfture of Mars, according to Baume, is 
a mixture in water of equal parts of fulphat of iron and 
of acidulous tartarit of potafli; the mixture is to Hand 
till a dry pulverulent matter remains; then digeft al¬ 
cohol over it with a gentle heat till it has acquired a 
yellow colour; draw off the liquor, filtre, and dry the 
refidue ; pour on frefli alcohol, and digeft as before. 
Peres has given another procefs in the Journal de 
Pharmacie, p. 154. Take two parts of iron-filings, over 
which place in digeftion, in a gentle heat, one part of 
pure tartareous acid, diftblved in the lead poffible quan¬ 
tity of water : when the acid is very red and much i ad- 
ed with iron, add as much alcohol as may be judgeci 
neceffary. 
There are likewife two other medical preparations, 
formed 
