628 
LECTURES ON THE BRITISH PHARMACOPEIA. 
Hard soap is prescribed, and is defined as being “ greyish-white, dry, inodorous.” It 
is ordered to be made from soda and olive oil. Some was accordingly prepared, and the 
liniment was accurately made from it, excepting that a small portion would not dissolve 
as long as the heat did not exceed 70°. This liniment had only a faint greenish tinge of 
colour, and remained fluid when exposed to great cold. It was doubtless such a prepara¬ 
tion as was intended should be produced. Since a pure olive-oil soap was not a commer¬ 
cially recognized substance, it was needful to examine the soaps which were often used 
for this purpose, and the following are some experiments:— 
1. Mottled Castile soap digested at 68°, as prescribed by British Pharmacopoeia, gave 
12 per cent., insoluble residue (margarate of soda), and the product did not gelatinize in 
the cold. 
2. The same at 120°: all dissolved, but the proportion of margarate of soda was too large 
to be retained at a low temperature, and gelatinization followed. 
3. White Castile soap at G8° left 27 per cent, residue. 
4. The same at 120° dissolved, but gelatinized. 
o. The olive-oil soap at 68° left 5 per cent, residue, and continued fluid at 32°. 
G. The same at 120° dissolved entirely, and also remained fluid at 32°. 
This experiment confirmed the statement of Groves (Pharm. Journ. vol. xviii. p. 502), 
that an olive oil which had lost much of its margarin by deposition in cold weather, 
would dissolve to a greater extent than is ordinarily the case with hard soap. 
Mr. Abbott submitted that these experiments were sufficient proof that neither kind 
of Castile soap ought to be employed, and especially they indicated that if the white 
variety were used, the liniment would contain less than three-fourths of the quantity of 
soap which it should. He believed that it contained much stearate of soda, from the use 
of animal fat. 
Mr. Yewdall read a short paper upon “ The Value of the Marc left in the Preparation 
of Tincture of Opium.” 
His object was to compare the processes of maceration and percolation respectively as 
affecting this. Tincture of opium was prepared, in a York Glass Company’s percolator, 
from pulv. opii. turc. mixed with half its bulk of sand. The loss of proof spirit was at 
the rate of six ounces per gallon, after pressing the marc. The marc was then 
treated with repeated quantities of distilled water, the washings concentrated and sub¬ 
mitted to processes which were described, for the separation of morphia and the other con¬ 
stituents. 
For comparison with Mr. Davis’s results upon the marc of tincture made by maceration 
(Pharm. Journ., n. s., vol. v. p. 462), Mr. Yewdall stated the morphia from the marc 
of three gallons of percolated tincture as being 16’8 grains, against 42 grains found 
by Mr. Davis in the marc of macerated tincture. 
These comparisons do not inform us of all that it is desirable to know, because the 
samples of opium used were not the same. 
The author alluded to the various modified processes that have been suggested for 
making tincture of opium, and expressed approval of that which adopts a hard watery 
extract instead of the crude drug, as giving a nearer approach to uniformity of result. 
The President announced that this would be the concluding meeting of the present 
session. 
LECTURES ON THE BRITISH PHARMACOPOEIA. 
ON THE RELATION OE THE BRITISH PHARMACOPOEIA TO 
PHARMACOLOGY. 
Lecture II. 
Delivered before the Members of the Pharmaceutical Society , April 20, 1864/ 
BY DR. JOHN ATTFIELD, E.C.S., 
DIRECTOR OF THE SOCIETY’S LABORATORIES. 
In considering the preparations of the Pharmacopoeia with the view of ascef-* 
taining to what extent the authors of the work have succeeded in representing 
