THE ALUMNI JOURNAL 31 



[Reprinted from the Aiueriean Drui^gist and Pliarmaeeutical Rceord 



for October 9, 1905.] 



PERMANENT OINTMENT OF RED MERCURIC OXIDE.^ 



Bv Utto RaubenheiiMer, Pir. G., Brooklyn, X. Y. 

 Many druggists have experienced annoyance on account of the 

 instabihty of the ointment of red mercuric oxide. We prepare a 

 C|uantity and in a few days or a month, when we have occasion to 

 use it, we find the upper part gray or black and are obliged to throw 

 it away. In order to obtain information on this subject I presented 

 a query at the 1904 meeting (A. Ph. A. Proceedings, vol. 52, p. 255), 

 "How May Ung. Hydrarg. Oxid. Rub. be prepared so it will keep 

 a nice red color?" Unfortunately this query remained unanswered, 

 so I made experiments myself and in October, 1904, succeeded 

 with the following formula : 



Red mercuric oxide, in very fine powder... 10 Gm. 



Castor oil 5 Gm. 



Petrolatum 85 Gm. 



Triturate the red mercuric oxide with the castor oil until a per- 

 fectly smooth mixture results, then gradually incorporate the pe- 

 trolatum and mix thoroughly. 



In the preparation of this ointment I use a glass mortar and 

 pestle and a horn spatula. Never use a steel spatula, as the iron 

 will reduce the mercuric oxide to metallic mercury, thus causing 

 the gray or black color. 



■ Put the finished ointment into the jar, smooth the top of the 

 ointment and cover with about i inch of water. Whenever you 

 have occasion to use the ointment take it evenly off the top with 

 a horn or rubber spatula and smooth it out again. Never dig any 

 holes into the ointment or leave any ointment around the top of 

 the jar by wiping the spatula thereon. I, by the way, make this 

 a point with all my ointments. 



It is not necessary to change the inch of water on top of the oint- 

 ment. The water keeps the air away. 



I have a jar of this ointment on hand which is almost a year old, 

 prepared in October, 1904, and which has not changed since in the 

 least. 



1 Presented to the American Pharmaceutical Association at the Atlantic City 

 meeting, September, 1905. 



