416 
LECTURES ON THE BRITISH PHARMACOPOEIA. 
duct, as well as that obtained by other operators. I have compared it with the 
preparation made by the London Pharmacopoeia, and I certainly prefer the latter, 
as a more agreeable spirit, to which the name “ sweet spirit of nitre ” more 
fully applies. 
Collodium. —Among the new preparations introduced into the British Phar¬ 
macopoeia is Collodium, for the preparation of which a process is given, but of 
this 1 cannot speak more favourably than of that just noticed. The success in 
making collodion depends upon the quality of the pyroxylin employed for the 
purpose. The Pharmacopoeia gives a process for making the pyroxylin to be 
used in the production of the collodion, but on trying the process I have ob¬ 
tained an insoluble, and not a soluble cotton. Such a result was just what I 
should have anticipated ; for in the process given the strongest nitric and sul¬ 
phuric acids are directed to be used, which would yield very good gun-cotton, 
if required as an explosive agent, but it is well known that good gun-cotton is 
not soluble in the mixture of ether and alcohol, and that to obtain a cotton that 
is soluble, and suitable for making collodion, the acids should be mixed with a 
portion of water, and should be used at a certain fixed temperature, with refer¬ 
ence to which no instructions are given in the Pharmacopoeia. 
One other preparation I have yet to refer to, and that is Distilled Water. 
The description given of the distilled water directed to be used in pharmacy, 
affords a good illustration of what appears to me to be a defect in many parts 
of the work; and that is an attempt at too great refinement. We are told that 
distilled water should answer to the following character, among others, namely, 
“ that a fluid ounce of it evaporated in a clean glass capsule leaves no visible re¬ 
sidue.” Now, I should like to see such distilled water made by simple distil¬ 
lation with a copper still, as described in the Pharmacopoeia. In the instruc¬ 
tion of pharmaceutical pupils I have been accustomed to set them the task of 
producing such distilled water, as one which they would think very easy, but 
which experience proves to be attended with considerable difficulty. 
ON THE ORGANIC MATERIA MEHICA OF THE BRITISH 
PHARMACOPOEIA. 
Lecture I. 
Delivered at the Pharmaceutical Society of Great Britain, on the 2ith of February, 1864. 
BY ROBERT BENTLEY, M.R.C.S. ENG., F.L.S., HONORARY FELLOW OF KING’S 
COLLEGE, LONDON, 
PROFESSOR OF MATERIA MEPICA AND EOTANY TO THE PHARMACEUTICAL SOCIETY OF 
GREAT BRITAIN; PROFESSOR OF BOTANY IN ICING’S COLLEGE, LONDON, 
AND IN THE LONDON INSTITUTION. 
The recent publication of a Pharmacopoeia which an Act of Parliament declares 
shall alone be used in the British Islands, cannot but be a source of gratification to 
all classes in the kingdom, and an event in which Medical Practitioners and Phar¬ 
maceutists especially must feel the greatest interest. There is no subject, there¬ 
fore, that is so well adapted at the present time for bringing before the Members, 
Associates, and Pupils of the Pharmaceutical Society, in a course of lectures, as a 
general account of the history, construction, nature of the changes, and descrip¬ 
tion of the new remedies of the first British Pharmacopoeia. When we con¬ 
sider the great difficulties that the framers of this national work have had to 
encounter, I feel sure you will all agree with me, that whatever errors it may 
contain and whatever its shortcomings may be, we should make all reasonable 
allowance for them, and approach its consideration and critical examination in a 
hilosophic and kindly spirit, and with an anxious desire of finding out its 
merits rather than its defects. At the same time, it is imperatively necessary 
