282 CHE M 
This combination is more quickly effefted, by mixing 
mercury with melted fulphur. The mixture being ftir- 
red up immediately, becomes black, and very readily 
takes fire. In order to preferve it black, it mult be taken 
irom the fire, the flame extinguilhed as foon as it be¬ 
gins to appear, and the matter mull be flirted till it be¬ 
comes fqlid, and in lumps. It mull then be pulverized, 
mid palled through a fine fieve. When this compound 
(four parts ot powdered fulphur to one of mercury) is 
expofed to a conliderable degree of heat, it takes fire, the 
greatell part of the fulphur burns, and after the combuf- 
tiori a matter remains, which, when pulverized, is of a 
violet colour. This powder is put into matrafles, which 
are heated till their bottoms become red, and kept in this 
Hate for feveral hours, till it appears that the matter is 
entirely fublimed. An artificial cinnabar, or red fulphure 
or mercury, is found fublimed to the upper part of the 
matrafs, in cryllalline needles, of a reddifn brown. It is 
of a lighter and more lively colour, when fublimed in 
retorts. The Dutch prepare in the large way the cinna¬ 
bar employed in the arts; it is made in loaves of various 
thicknefs, and divided by layers which mark the different 
iublimations made in the fame veffel, without feparating 
the cinnabar from the preceding fublimatior.s. 
The fulphure of red mercury, or cinnabar, levigated 
with water on marble, lofes much of the intenfity of its 
colour, and becomes of a fine bright red, by reafon of its 
extreme divifion; afterwards it is put into a large quan¬ 
tity of water, and the powder left to fettle; then draw 
off the water, and dry the powder: this is called Vermil¬ 
lion; it is much ui'ed in painting, and fometimes in me¬ 
dicine. 
If die black fulphure of mercury be boiled with pot¬ 
ash it is converted into cinnabar: Berthollet, who re¬ 
peated die experiment, fays he ufed pure potalh, but that 
it required a long ebullition to produce the efvefit. Cin¬ 
nabar is not decompofed by the aftion of fire in clofe 
veflels; when heated in open veflels, the fulphur burns 
gradually, and the mercury is volatilized. Many fub- 
llances are capable of decompofing red fulphure of mer¬ 
cury, by virtue of their affinity to fulphur. Lime and 
alkalis have this property; when thefe are heated in a 
retort, with twice their weight of cinnabar, running mer¬ 
cury is obtained, and the reiidue is found to be an alka¬ 
line or earthy fulphure. Many brittle metals, fuch as 
cobalt, bifmuth, and antimony, have likevvife the pro¬ 
perty of depriving mercury of its fulphur. And almoll 
all the duftile metals, lead, tin, iron, copper, and filver, 
Lave Jikewile a ftronger affinity with fulphur than mer¬ 
cury, and confequently decompofe cinnabar. But iron 
is principally ufed to fsparate the . mercury from this 
compound. The metallic fluid obtained by thefe pro- 
cefles is perfeftly pure, and is diftiirguiflied by the name 
of mercury revived from cinnabar. 
Mercury immediately decompofes alkaline fulphures, 
but produces different phenomena, according to the na¬ 
ture of thefe compounds, With a folution of hydroge¬ 
nated fulphure of potalh, it is reduced to a black ful¬ 
phure, which in the courfe of feveral days becomes red. 
With hydro-fulphure of ammoniac, it becomes a black 
powder, The hydrogenated fulphure of ammoniac changes 
the mercury itfelf into a black powder ; but in a few days 
.this powder affumes a beautiful red colour; the fiiper- 
natant liquor becomes at the fame time colourlefs. It 
may be decompofed by muriatic acid ; and much fulphu- 
.rated hydrogen gas is dilengaged, without any precipi¬ 
tation. of fulphur. 
From this experiment it appears, that the mercury 
combines at full with the fulphur and fulphurated hy¬ 
drogen ; but tire ammoniac regains by degrees the- ful¬ 
phurated hydrogen, by giving out fulphur; fo that, at 
the end of the operation, the fulphur is found entire with 
the mercury, and the fulphurated hydrogen with the am¬ 
moniac. The new combination is black, becaufe it con¬ 
tains fulphurated hydrogen; it becomes red, becaufe 
I S T R Y. 
the fulphurated hydrogen has been taken away by the 
ammoniac, which has given out fulphur in exchange ; 
but with the hydro-fulphure of ammoniac this exchange 
cannot take place. This difference there is then between 
the black fulphure of mercury and the red,, that the firfl: 
contains more or lefs of fulphurated hydrogen,- while the 
lad is an unmixed fulphure; the firfl; is hydrogenated 
fulphure, the laft is fulphure of mercury. Fourcroy dis¬ 
covered, that by ftirring mercury in water charged either 
naturally or artificially with fulphurated hydrogen gas, 
,it. would be quickly decompofed, and converted into a 
black fulphure. 
To phofphorize mercury, put into a matrafs equal 
parts of the red oxyd of mercury and pliofphorus; add 
a little water, and then place the matrafs over a warm, 
land-bath : fltake the matrafs from time to time, and 
keep it a long while on the fire. The oxyd of mercury 
becomes black, and then unites with the phofphorus 
the water becomes acid, and contains phofphoric acid. 
In this experiment, the oxygen contained in the oxyd of 
mercury, quits the metal to attack a portion of the phof- 
phorus, which it changes into phofphoric acid; then the 
mercury, deprived of its oxygen, is in a Hate of extreme 
divifion, and thus it unites with phofphorus, forming a 
peculiar combination, in which the phofphorus predomi¬ 
nates; this produft foftens in boiling water, and takes a 
confluence as the water cools. This pliofphorated mer¬ 
cury is to be put into a bag of chamois leather; hold it 
in boiling water, and fqueeze it'gently; a little tranf- 
parent phofphorus comes through ; and there will remain 
in the bag pliofphorated mercury, of a firm conliftence, 
black colour, breaking under the knife ; on examination, 
it will appear to confiit of little molecules of mercury not 
well combined. This phofphure of mercury, expoled to 
a dry air, emits white vapours with a phoiphoric odour. 
The combination is broken by diftillation : the pholpho- 
rus pufles over firfl:, then the mercury ; and both will be 
found in the receiver, entirely feparate. 
Mercury does not feem to diflolve in Water. Phyficians 
are, neverthelefs, in the habit of caufing a bag full of this 
metal to be fufpended in vermifuge decoctions during, 
their ebullition ; and experience has fliewn, that this 
practice is attended with good eflefts. Lemery affirms, 
that mercury lofes nothing of its weight by this decoc¬ 
tion. It is probable, that-a principle, fimilar to that of 
fmell, emanates from the mercury, a principle fo fugitive 
and fubtle, that its weight cannot be found. It is per¬ 
haps this principle that communicates the anthelminthic 
virtue to water. 
Neither arfenic nor cobalt will unite with mercurv. 
Bifmuth, however, unites completely; hence ariles a 
bright friable matter, more or lefs lolid, according to the 
proportion of bifmuth: this amalgama cryftallizes in 
four-fided prifms, which fometimes unite in octahedrons. 
When heated in a retort, this mixture parts with its 
mercury with great difficulty. There is no union with 
nickel, or with antimony. 
The fulphuric acid does not aft on this metallic fub- 
ffance but when it is well concentrated and hot. To 
make this folution, one part of mercury is poured into a 
glafs retort, and one part and a half or two parts of con¬ 
centrated fulphuric acid are added ; the mixture is heal¬ 
ed, and a violent effervefcence is loon after . excited ; the 
furface of the mercury becomes white, and a powderof the 
fame colour is feparated, which renders the acid opake; 
and a large quanti ty of fulphureous gas is dilengaged, 
which may be collected over mercury. This, method, as 
we have leen in Ipeaking of the fulphuric acid, is mod 
commonly ufed to obtain that gas. A portion of water,; 
charged with fulphureous acid gas, iikewife pall’es over. 
When thi s, dill illation rs urged till the fulphureous acid no. 
longer palles over, a white opake veryeaufiic mafs is formed 
at the bottom of the retort, which weighs one-third more 
than the mercury made ule. of, and Itrongly attrafts the 
humidity of the air. The greateft. part of this mafs is an 
