LECTURES ON THE BRITISH PHARMACOPEIA. 
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stated to contain, namely, 29'84, is quite in accordance with the experiments of 
Bastick, who showed that the preparation could not contain more than about 30 
per cent, instead of 34 per cent, as stated in the London Pharmacopoeia. 
Hydrargyri Ciiloridum. —What is Hydrargyri Chloridum ? According to 
the old Pharmacopoeias it was calomel, according to the new Pharmacopoeia it is 
corrosive sublimate. Now it is not my intention to say anything against the 
employment of the terms calomel, corrosive sublimate, red iodide of mercury, 
green iodide of mercury, red oxide of mercury, and ammoniated mercury; every 
jaescriber and dispenser knows what is meant by them, and perspicuity should 
be the primary consideration in pharmacopoeial nomenclature. Nor have I any 
remarks to make on the processes for the preparation of these substances. But 
the adoption in the British Pharmacopoeia of new views of the atomic constitu¬ 
tion of mercury and its salts, and the thrusting of those views on prescriber and 
dispenser without previously consulting or warning them, is, in my opinion, a 
proceeding uncalled-for, inexpedient, and dangerous. For will not the physician 
who objects, or is unaccustomed to use the terms Calomelas and Hydrargyri Cor- 
rosivum Sublfmatum, continue to use the term Hydrargyri Chloridum, or its con¬ 
traction, Hyd. Chlor. ? Assuredly'he will, and the consequence will be endless 
anxiety and trouble to the druggist, and possible salivation, or even death, to the 
patient. 
But this proceeding is one which, so far from indicating a desire in the com¬ 
pilers of the work to keep pace with the progress of science, exhibits that disre¬ 
gard of recent researches which is so frequently evident in the book. On the 
19th of November, 1863, two months before the Pharmacopoeia was published, 
Dr. Frankland read a paper before the Chemical Society on a new method of 
producing certain new mercury compounds, from which, among other important 
results, it was obvious that the question regarding the atomic constitution of 
mercury salts might be considered to be settled ; settled, moreover, in accordance 
with the constitution ascribed to these salts in the last London, Edinburgh, and 
Dublin Pharmacopoeias. This paper gave rise to some interesting discussion, in 
the course of which the President, Professor Williamson, said that by the light 
of these researches the constitution of corrosive sublimate could not be viewed 
otherwise than as the bichloride of that metal. The discussion and an abstract 
of the paper were published, on the 28th of November, in the ‘Chemical News’ 
(p. 262), and shortly afterwards in the Chemical Society’s own Journal (1863, 
p. 415). There was thus ample time for the authors of the Pharmacopoeia to 
detect and reject their new and erroneous views, had they desired to do so. 
If names other than, or rather in addition to, those of calomel and corrosive 
sublimate were desired for the two chlorides of mercury, to meet the wishes of 
medical practitioners who think it objectionable in the interests of their patients 
to use those names, or who may occasionally find it absolutely necessary to keep 
from their patients the knowledge of the fact that they are taking calomel or 
corrosive sublimate, such additional names could very well be found; names that 
are in constant use by scientific men of all countries, names which correctly and 
shortly express difference of composition, but which are perfectly independent 
of the constitution of the salts they are used to designate. 
Hydrargyrum cum Creta is still retained in the Pharmacopoeia, although 
it has been repeatedly shown to be most uncertain in its action, and the cause 
to be the varying amounts of black oxide or red oxide of mercury inevitably 
present in it. 
Infusa. —The most noticeable point in connection with the infusions in the 
new Pharmacopaeia is the short time during which the ingredients are to be 
kept in contact with the water, as compared with the periods of maceration 
ordered in the last London, Edinburgh, and Dublin Pharmacopoeias. The fol¬ 
lowing Table shows these differences at a glance :— 
