548 
JOTTINGS ON THE BRITISH PHARMACOPOEIA. 
ance of composition the superstition of former ages brought into vogue,"* and 
whose efficacy, when the proper simple for a case in treatment is found to 
answer better, may be compared to that of “ accumulatiug all the medicinal 
simples into one form ” to “ make a remedy against all diseases.”* 
It is our duty to assist, not to obstruct, the therapeutist in his investiga¬ 
tion of the action of medicines on disease. He has a wide field of labour, in 
which comparatively little is known—medical treatment at present being 
quite empirical; stiil such rapid strides have of late been made in this direc¬ 
tion, that the day may not be far distant when the practice of medicine may 
stand on a definite scientific basis. 
University College Hospital , Feb. 22nd , 1870. 
JOTTINGS ON THE BRITISH PHARMACOPEIA. 
BY J. F. BROWN. 
The following are strictly what the title describes them to be—jottings 
made during a course of reading for the Major Examination. 
Some of them, I am aware, possess but slight importance, although the 
recent discussions at the evening meetings of the Society may render them 
opportune; and to all of them I would solicit the kind attention of fellow- 
students, that my corrections may be, if need be, themselves corrected. It 
may be convenient to note a few proposed emendations of the text,— 
P. 36. After the dose of ammonii chloridum, insert “ preparation in which 
chloride of ammonium is used— 
Liquor Ammonia? Fortior.” 
152. Third line from bottom, insert— 
“ Hydrargyrum Ammoniatum.” 
179. Seventh line from bottom, insert— 
“ Spiritus Ammonise Foetidus.” 
The following are less palpable, and require explanation :— 
P. 18. Thirteenth line from top. for “ 215 5 ” read “ 202'75 ” grains. 
142 parts by weight of phosphoric anhydride, P 2 0 5 , will produce 811 parts 
of phosphate of lead, Pb 3 P 2 O s ; therefore 355 grains of the officinal acid, 
which contains 10 per cent, by weight of the anhydride, can only } T ield 202‘75 
grains of the lead salt. 
P. 183. Twentieth line from top, for “ 9'92 ” read “ 9'905.” 
The quantity stated in the Pharmacopoeia is apparently based on the as¬ 
sumption that exactly 3 grains of oxide of bismuth are contained in each fluid 
drachm of the solution, whereas the quantity, calculated from the weight of 
metal employed, is 2‘994 grains, and therefore the weight of sulphide obtained 
from three fluid drachms can only be 9'905 grains. 
My few remaining notes and queries I have arranged alphabetically. 
Ferri Arsenias, Fe 3 As 2 O s .—The note appended to this formula, “ partially 
oxidized,” hardly conveys to the mind an accurate idea of the average con¬ 
dition of this salt, since two-tliirds of the iron may pass into the ferric state, 
without its ceasing to fulfil the conditions of the volumetric test. Twenty 
grains of Fe 3 As 2 O s contain 7‘5 grains of iron; but the 170 grain-measures 
of the volumetric solution of bichromate of potash used to test that weight of 
the arseniate, are only capable of peroxidizing 2 856 grains of the metal. 
Ferri Carbonas Saccharata.—The volumetric test given for this preparation 
erroneously indicates the presence of 57'4 per cent, of ferrous salt. The whole 
* ‘ The New Dispensatory,’ London, 1770, p. 593. 
