Memoir wpon Animal Fat. 107 
so little oxygen, yields any part of it to the muriatic acid, 
and makes it pass to the state of oxymuriatic acid. 
I made the comparison with different ointments, which 
had been prepared three months, eight months, and several 
years; in the latter compounds I found a little oxidated 
mercury, but the greatest part was always in the metallic 
“State. 
I also triturated mercury with Venice turpentine ; and it 
was absorbed with great facility. To ascertain if the mer- 
cury obsorbed the oxygen from the air, or if it got any oxy- 
gen from the turpentine, J dissolved the mass. in alcohol at 
40°; all the turpentine was dissolved, and-the mercury was 
precipitated in small globules; the alcoholic solution was 
afterwards evaporated : ,I then obtained the turpentine with 
all its. properties. 5 
It results, therefore, that in the ointments above men- 
tioned the mercury is not in the state of..an oxide, as gene- 
rally supposed, but that it is in, the metallic state, and in 
very minute division, particularly in newly prepared oint- 
ment. I am of opinion that mercury is inva similar state 
in several mercurial compounds, more or Jess in wse,,as in 
the vigo-mercurial plaster, ethiops saccharatus, ethiops alka- 
lisatus, or mercurius gummosus Plenki, &c. of the shops, 
It may be objected that the colour of the ointment and of 
the above preparations speaks very much for the oxidation 
of the mercury; but let glittering antimony, bismuth, or 
any other metal susceptible of pulverization be reduced toa 
fine powder, and it will be seen that these substances are of 
a blackish gray when in minute division. 
It remains for. me to speak of the action of fat upen the 
metallic salts. I shall confine myself more particularly to 
the nitrate of mercury, from which a compound results very 
much used in pharmacy. 
I prepared the citrine mercurial ointment according to the 
process described in Baumé’s Elements of Pharmacy, by dis- 
solving three ounces of mercury in four ounces of nitric acid 
for two pounds of fat. 
As the surface of this ointment always becomes white 
after some time, the cause of which is only explained by 
asserting 
