TRANSACTIONS OF THE PHARMACEUTICAL SOCIETY. 305 
the substitution of barberry bark for the officinal pomegranate root-bark. Th 
former might be readily distinguished bj T its great bitterness. 
NOTE ON RED OXIDE OE MERCURY OINTMENT. 
BY MR. T. A. BARBER. 
In the Pharmaceutical Journal for last June, Mr. Mee made favourable 
mention of my recommendation to substitute yellow for white wax in the Uno-. 
Ilyd. Nit. Oxidi of the P. L. 1851. It certainly kept much longer without 
change, and I continued so to prepare it till the appearance of the British Phar¬ 
macopoeia, when preferring, if possible, to adhere to the legal directions, I made 
it as ordeied, of white wax, lard, and almond oil. The consistence was much 
improved, and this is all that can be said in its favour; for, by keeping, it not 
only became discoloured, but also rancid, an affliction to which the old ointment 
being harder, was less subject. 
The recipe that I now propose, and by which I have made some that remains 
after four months as good as when first prepared, is—• 
Ilyd. Nit. Oxidi ~j. 
Cer. Flavrn gij. 
01. Amygdalae *vj. 
Misce ; fiat unguentum. 
I thus discard both white wax and lard, discoloration being chiefly due to 
the former, and rancidity to the latter. The result has been an ointment which, 
for consistence and persistence, leaves nothing to be desired. 
1 rofessor Redwood said the note which had just been read was sent for 
insertion in the 1 Pharmaceutical Journal,’ but at his request the author had 
consented to its being read at the meeting. Short as the communication was, 
it related to a subject the introduction of which might elicit some discussion, and 
he was anxious, in common with others, to encourage the discussion of such 
subjects, especially at the present time, when the Pharmacopoeia was under 
revision. There were two or three points to be considered with reference to Red 
Oxide of Mercury Ointment. In the first place, was the oxide made by heating 
nitrate of mercury, or that made by precipitation, best suited for the purpose? 
It would be recollected that several months ago Dr. Balmanno Squire recom¬ 
mended the substitution of precipitated oxide of mercury for the ordinary red 
precipitate in making the ointment, the precipitated oxide, which has precisely 
the same chemical composition as the other, being in a more uniformly minute 
state of division, and forming an ointment which, according to Dr. Squire’s 
statement, possesses greater smoothness, and is therefore less likely to irritate 
the skin. It would be desirable to ascertain whether the ointment made with 
the precipitated oxide would admit of being kept without change as well as that 
made with red precipitate. Then with reference to the use of yellow (un¬ 
bleached) wax, it appeared from the statement of Mr. Barber that the ointment 
made with this was less subject to change than that made with bleached wax, 
and this corresponded with observations which he (Dr. R.) had made in some¬ 
what similar cases. 
The Chairman observed that the preparation of ointments was one of con¬ 
siderable practical importance, as inconvenience was frequently experienced 
from their tendency to become rancid. There was one point he would mention 
that could not be too carefully attended to, and that was to have the pots in 
which ointments were kept for use perfectly cleansed, by scalding them out 
before putting freshly-made ointments into them. This was often neglected, 
