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PREPARATION OP MERCURIAL OINTMENT. 
ART. XXXII— ON THE PREPARATION OF MERCURIAL 
OINTMENT. 
By M. Fossembras. 
There are few pharmaceutical preparations that have 
given rise to so many investigations and theories as mer- 
curial ointment. So much has been said on the subject 
that anything new may at the very outset appear fastidious 
and useless. 
It is with some hesitation therefore that I publish these 
considerations, which have suggested to me the employ- 
ment of a process which allows S lbs. of mercurial oint- 
ment being prepared in less than one hour. The process 
which I employ consists simply in the use of rancid fat, but 
it is so easy of execution that I have thought, it right to res- 
cue it from the oblivion into which it has fallen. Only 25 
grms. of this substance are requisite for a pound of oint- 
ment, and so small a quantity is not capable of communi- 
cating injurious properties to a medicine which can never 
be preserved for any length of time from becoming rancid, 
and which is scarcely ever employed in any other state. 
The requisite conditions for a prompt division of the metai 
may be reduced to two, — 1st, dividing by trituration ; and 
2d, preventing the reunion of the separated particles. The 
first condition is always complied with, but the second 
scarcely ever. In fact, fresh lard not possessing any aggluti- 
native properties can for that very reason not retain the 
mercurial powder and prevent the reunion of its particles. 
Fresh lard therefore is incapable of extinguishing mercury 
in a perfect manner. 
It may perhaps be objected, that a continued vigorous 
working is always followed in a short time by success; to 
which I would answer, that I have never seen the work 
terminated before the fat has acquired a rancid odor. 
