C H E M I 
Neutral falls have fcavcely any a&ion on mercury. 
Tliough this affertion is more efpecially applicable to the 
different l'ulphats, Fourcroy oblerved, neverthelefs, that 
mercury becomes very quickly extinguilhed in fulphat 
of potafh. 
Mercury does not appear capable of altering ammo- 
niacal muriat by dillillation. Bucquet, who made this 
experiment, obterved, that two parts or mercury are not 
well extinguilhed by one part of this fait, and that the 
mixture does not afford ammoniac by diltillation. The 
count de la Garaye, neverthelefs, prepared with thefe 
two fubtlances, a medicine, to which he gave the name 
of tintture of mercury. Macquer, who examined his pro- 
cefs, found it to fucceed perfectly well. It confided in 
triturating one ounce of running mercury, with four 
ounces of ammoniacal muriat, in a marble mortar, moift- 
ening the mixture with a fmall quantity of water, till the 
mercury entirely difappeared. This matter being left 
expofed to the air five or fix weeks, and from time to 
time agitated, is then to be triturated afrefh, and after- 
tjvards expofed in a matrafs on a fand-batli, covering the 
powder to the depth of about two inches with good fpi- 
rit of wine. The mixture being made to boil flowly, 
the alcohol affumes a yellow colour, and contains mer¬ 
cury, as appears from its whitening a flip of copper. 
From this experiment it appears, that the ammoniac is gra¬ 
dually difengaged by the mercury ; that ammoniaco- 
itiercurial muriat is formed, part of which is difl'olved 
by the fpirit of wine ; and that the different quantity of 
the mercury, and the flow aftion produced during the 
maceration, are the caules of the difference between this 
experiment and that of BuCquet. The red fulphure 
of mercury may be made to detonate with the fuper-oxy- 
genated muriat of potafh ; but does not flame with the 
fulphuric acid. 
Mercury combines with many other fubflances, as 
gums, fyrups, vegetable acids, See. as will appear in the 
courfe of this treatife. Mercury is of the molt extenfive 
tile in the arts, fuch as gilding, filvering of glaffes, con- 
ftru&ing of meteorological inftruments, metallurgy, &c. 
it is ufed in medicine in a great variety of forms. Crude 
mercury was formerly employed in the iliac paffion. It 
is kill boiled in w'ater, to which it communicates a ver¬ 
mifuge property. Mixed with fat fubflances, it forms an 
ointment ufed in venereal diforders. Turbifh mineral, or 
yellow oxyd of mercury by fulphtiric acid, has likewife 
been recommended in the fame diforders, in the dofe of 
a few grains. This medicine is emetic and purgative in 
a high degree. Mercurial water, or its nitric folution, is 
ufed by furgeons as a powerful efcharotic. Red precipi¬ 
tate, or red oxyd by the nitric acid, anfwers the fame 
purpofe. A citron-coloured ointment is prepared with 
hog’s lard and the nitric folution of mercury, which is a 
certain cure for the itch. Corrofive mercurial muriat has 
been recommended by Sanches and Van Swieten, in ve¬ 
nereal diforders. A few grains are difl'olved in brandy, 
and a fpoonful of this folution is taken at a time in a 
large quantity of mild liquid. The exhibition of this 
remedy requires great care, more efpecially with regard 
to the ftate of the ftomach and lungs. Mild mercurial 
muriat, given in the dofe of twelve or fifteen grains, is a 
purgative, and in the dofe of three or four grains, is an 
alterative. The phagedenic water is ufed in lurgery to 
corrode and deftroy fungus, or proud flelh, &c. Mercu¬ 
rial borat has been ufed with fuccefs in venereal diforders 
by Chauflier the younger, of the academy of Dijon. Cin¬ 
nabar has been confidered improperly as an anti-fpafmo- 
dic and fedative medicine. It enters into the compofition 
of the pulvis temperans of Stahl, which is prepared ac¬ 
cording to the Pharmacopeia of Paris, by accurately mix¬ 
ing three grains of fulphat of potafh, and of nitrat of 
potafh, vitriqlated tartar and nitre, with two fcruples of 
artificial cinnabar. This compound is ftill ufed, by ex- 
pofing the patients to its vapour. It then conftitutes one 
S T R Y, 287 
of the methods of treatment of venereal diforders by fu¬ 
migation. 
_ All the preparations of mercury, which are internally 
given, produce very beneficial eft'etfts in other diforders, 
as well as thole of the venereal kind ; fuch as moft dit- 
orders of the fkin, fcrophulous diforders, lymphatic fwel- 
lings, &c. We cannot, however, forbear obferving, that 
thefe medicines, more efpecially the faline mercurial pre¬ 
parations, ought not to be applied but by experienced 
and cautious phyficians; and that it is dangerous to the 
health, and even to the life of men, that mercurial reme¬ 
dies fliould be in the hands of a great number of perfons, 
who, generally fpeaking, are deficient, not only in the 
knpwledge which is necefl'ary to adminifler them with 
fuccefs, but even in that knowledge which might enable 
them to avoid danger. 
Of ZINK. 
Native zink is very rare; naturalifts even doubt whe¬ 
ther it exifts at all. The ores of zink are not worked for 
the purpofe of gaining this metal. It is obferved, during 
the finelting of lead-ores mixed with blende, that the 
zink is fublimed in the chimneys of the furnaces, in the 
form of an oxyd, and produces greyifli incruftations, 
named inttia, or cadmla fornaciun. Another portion is 
obtained in the metallic form, by cooling the anterior 
part of the furnace. The zink, being driven up in the 
vapourous form by the aftion of the fire, is condenfed in 
this place, and falls in fmall grains into powder of char¬ 
coal, which covers a done placed below. This metal is 
preferved from oxydation by the powder of charcoal, 
and is afterwards melted in a crucible, and run into 
moulds. Such is the procefs by which the greateft part 
of the zink found in commerce is obtained at Rammelf- 
burg, whether in the ftate of oxyd or metal. This zink. 
is always united to a certain quantity of lead : it feems 
that the zink prepared in China, which comes to us un¬ 
der the name of tutenag, is much purer, but the manner 
of preparing it is unknown with us. Sage ftates, that 
the Englifltobtain zink in the large \*ay, from lapis cala- 
minaris, by diftillation ; but the method is kept a fecret. 
Zink is a brilliant bluilh white metallic fubftance, cryf- 
tallized in narrow plates. It has neither tafte nor ftnell. 
It cannot be reduced into powder like the other metals, 
but becomes flattened under the hammer, and may even 
be laminated, provided it has. not ■ previoufly been too 
much hammered. This experiment was made by Sage. 
When it is required to have zink in a ftate of extreme 
divifion, it muft be granulated, that is to fry, poured 
melted into cold water, or elfe reduced into filings. It 
has the inconvenience of choking up the files. Macquer 
affirms, that, when heated nearly to melting, it becomes 
very brittle, and may then be pulverized. This property 
is very different from that of the metals, which become 
more duftile by the aftion of heat, and qft'ords an advan¬ 
tageous procel's for obtaining zink in a ftate of extreme 
divifion. It may likewife be obtained in this ftate, by 
triturating it while melted, and keeping its particles 
afunder by continual motion, before they take the folid 
form by cooling. This operation muft not be made in 
an iron-mortar, becaufe zink always diffolves a portion 
of this metal; a mortar and peftle of marble muft be ufed. 
Mongez fucceeded in obtaining this metal in a regular 
form; for this purpofe he ufed a veffel pierced at the 
bottom and at its fides, with a number of holes which 
he flopped with earth of bones. When the' zink cools 
at its furface, the holes are to be opened gradually, 
and the metal agitated by a red-hot iron, introduced 
through one of thefe openings. This Ample procefs oc- 
cafions the melted portion of the zink to run out; the 
veffel is then to be iliaken, till no more melted metal runs 
out, and the cold portion cryftallizes. If it be left in the 
veflel, it retains its metallic colour ; but, if it be expofed 
to air, it takes a tarnilh of rainbow colours. When zink 
is 
