222 
BRITISH PHARMACEUTICAL CONFERENCE. 
Out of twenty-seven samples purchased in small quantities, at various 
places, only twelve could be certainly classed as genuine, although it must be 
a matter of some little difficulty now and then to distinguish absolutely a 
poor and inferior bark from one which contains an admixture of the same 
bark in a spent and exhausted condition ; it is here that the microscope does 
some good work. 
I will not take up your time to-day by entering upon a detailed exposition 
of the results, but will allow Table II. to tell its own story. The alkaloids 
were determined generally by the following method, which I find gives 
tolerably definite results :— 
200 grains or thereabouts of the bark to be examined are mixed with about 
half a drachm of bisulpliate of potassium, and enough hot distilled water 
added to make the whole into a rather thin paste, which is digested upon a 
water-bath for several hours, more water being added to supply the loss by 
evaporation, unless a closed vessel be employed, which is certainly preferable. 
A few drops of strong hydrochloric acid are next stirred in, and afterwards 
about three ounces of hot water rendered also slightly acid. If twelve or 
fourteen hours’ maceration can then be conveniently given, it will be well; 
if not, a shorter time will do, if the temperature be kept not much under 
200° E. After careful filtration and washing of the residue with more acidu¬ 
lated water, a mixed solution of the acetates of lead and aluminum will be 
found best for separating colouring matter, etc., if cautiously added to the 
filtrate, after which a second filtration will be necessary. The clear liquor 
must be concentrated by evaporation to a small bulk and a slight excess of 
pure caustic soda added thereto. The alkaloids present may be extracted 
directly from the liquid by successively agitating it with small quantities of 
pure ether, or it may be mixed with sufficient pure plaster of Paris to cause 
the solidification of the whole, and the cake thus formed after being carefully 
dried can then be very conveniently exhausted with anhydrous ether. 
The figures which appear in the fifth column of the table almost speak for 
themselves. fluorescence of soluble quinine-salts is here taken advantage 
of, and offers a ready method of comparing various samples of bark, for their 
quinine-value, both with each other and with a standard series of 100 tubes, 
containing graduated solutions of the pure alkaloid. 
I may in conclusion observe that in two or three instances my results have 
been confirmed by the confidential admissions of the vendors themselves, who 
have duly promised to amend their ways: they will doubtless join the 
“ British Pharmaceutical Conference ” as soon as their consciences are quite 
clear. 
Mr. Balkwill expressed the hope that assistants and pupils would be en¬ 
couraged to attend the meetings of the Conference. 
Mr. Cooper said that several were present yesterday. 
Mr. Inge recalled the meeting at Nottingham, when a considerable num¬ 
ber of the young men engaged in the town were present. 
Some discussion followed as to whether invitations should be sent to the 
medical practitioners of towns in which the meetings were held, in which 
Mr. Pale, Mr. Eadford, Mr. Xnapman, Mr. Guyer, and others, took part. 
It was stated that invitations had been issued to the physicians and surgeons 
of Exeter, but from the short notice given only a few had attended. 
The general feeling was that the Local Committee might on each occasion 
be entrusted with the power of invitation, the President expressing his 
opinion in favour of the attendance of medical men, and also hoping that all 
convenient facilities would be given by members to their young men. 
