REPORT ON THE PHARMACOPOEIA. 
277 
A great improvement, the Committee think has been 
effected in the introduction of equal parts, appended to each 
formula. The unequal system of weights existing in our 
shops, leads to the constant danger of the use of avoirdupois in- 
stead of troy weights, and this danger was greatly enhanced 
by the paucity which existed in the number of troy weights, 
to be found even in this city, a fact which rendered a nice 
calculation necessary where a formula was compounded, to 
convert the sole pile in the shop into its tro)^ equivalent. This 
inconvenience, and the consequences which must inevitably 
flow from it, is obviated by the employment of equal parts, 
which, however determined, must still retain their relative 
value ; and effectually prevent the results i which must ensue 
from the substitution of amounts so entirely dissimilar, as 
those of the troy and avoirdupois weight, expressed by identi- 
cal terms. 
But perhaps the amendment of most value, independent, of 
special modifications in particular formulae, has been the in- 
troduction of the process of Displacement or vegetable lixivia- 
tion, in the preparation of a large class of formulas, to which 
the experience of the Committee and others has found it ad- 
mirably adopted. It was early determined that the use of 
this process must be adopted, and it became an anxious ques- 
tion with the Committee, to say whether one general descrip- 
tion of the process should be prepared, and inserted in the 
former part of the work, or whether a detailed direction for 
its execution should follow each formula to which it was ap- 
plicable. Objections existed to both. To the. former mode 
it was opposed that] pharmaceutic directions were inconsist- 
ent with a Pharmacopoeia, as the Committee had determined 
by its own vote ; to the latter, there existed the incon- 
venience, monotony and tautology, of directions unwieldly in 
length, and in an almost identity of terms. The subject having 
been fully considered, it was finally concluded that an excep- 
tion to the general rule was admissible in the case of this 
new process ; that it would be depriving the profession of a 
most valuable agent, and the country of an important 
