PHAllM aceutical meeting. 
461 
Mr. Carteighe believed a good deal of misunderstanding had arisen about 
the meaning of the term jelly in reference to this liniment, for he had always 
associated the idea of jelly with that which one was accustomed to eat, having 
a somewhat yellow transparent colour. If this liniment were made with Castile 
soap, he had never been able to produce anything like that at all, but when 
made with soft soap, in various proportions, it was quite possible to make a 
very beautiful imitation of what he should call an edible jelly. It was certain 
that a great deal depended on the soap, for having made fifty or sixty experi¬ 
ments on this liniment with different kinds of soap at different times, he was 
astonished to find what different results were obtained with different soaps. 
Some time ago he met with a specimen of soap which professed to be genuine 
French Castile soap made with olive oil, and which was guaranteed by the 
seller to be what it professed to be. That soap yielded an excellent product, 
but it seemed to go very much further than the ordinary soap, although it was 
not sensibly harder, for he had dried it a short time and compared the amount 
of loss with that of an ordinary specimen, and found there was no material 
difference between the two. Still it seemed to have the sticky tendency in a 
greater degree than that which he was in the habit of using. He found that 
following strictly the directions of the Pharmacopoeia, cutting this soap up into 
extremely small pieces, not powdering it, he got a product which did not sepa¬ 
rate, and was not transparent, but which would bear dilution to a considerable 
extent; indeed, in one experiment he added as much as three ounces of water 
beyond the total weight of the ingredients used. He thought it would be well 
in future to mention the weight which the product should have, as according 
to the weight there would be very different degrees of limpidity. The speci¬ 
men of soap he had alluded to, although very excellent for this purpose was 
totally unfit for making soap-liniment, for when it was dissolved at a low tem¬ 
perature, it became quite gelatinous and unfit for use. The result of the dif¬ 
ferent experiments he had made tended to force conviction upon his mind, that 
the later recommendation of using soft soap was a very desirable one to intro¬ 
duce, as he thought it would tend to produce a more uniform product, and one 
more nearly answering the description given. He thought it would be better 
to use, if not all, at least one half of soft soap in the preparation. 
Mr. Wood said there was one point in Professor Redwood’s paper to which 
he thought it might be worth while to direct attention, namely, the alteration 
which he proposed in the Pharmacopoeia process for determining the alkaloids 
in cinchona barks. The process now given was to form an ethereal solution, 
which was to be evaporated to dryness, and the product taken as representing 
the weight of alkaloid extracted from the bark. Dr. Redwood proposed to 
modify this process by directing the ethereal solution to be evaporated, then 
dissolved in dilute sulphuric acid, and afterwards precipitated by ammonia, the 
precipitated alkaloid to be collected on a filter, washed, dried, and weighed. It 
so happened that he had quite recently been engaged in a number of experi¬ 
ments bearing on this very point, and he had come to a different conclusion to 
that advanced by Dr. Redwood. In fact, he was very strongly inclined to think, 
that the process as it stood gave more correct results, and was more easily 
carried out, than the one suggested. He had taken a definite weight of pure 
quinine, and tried it by both methods; and though he had very little difficulty, 
by evaporating the ethereal solution in arriving at a constant and correct esti¬ 
mate of the amount of quinine, by the other process he never could obtain 
perfectly uniform results, nor could he obtain them perfectly accurate. In the 
first place, there seemed to be a difficulty in precipitating pure quinine by am¬ 
monia. The difficulty of precipitating hydrates had been referred to by Dr. 
Redwood in the case of oxide of iron and carbonate of magnesia, and the same 
difficulty arose in precipitating the hydrate of quinine. If you took a solution 
