328 
INFUSUM CINCHONA SPISSATUM. 
article! ” The manifestly impartial nature of the plan corrected all this the 
second year. 
There is an important question in connection with the subject, upon which I 
will not enlarge here, viz. the question of what status we should give to those 
passing such examinations? I merely wish to say that it must be a recognition 
that the candidate (a Senior, for instance) is fully qualified to perform the duties 
of a Pharmaceutical Chemist. We must not do less than this, or we shall be 
unjust, and our illiberality will defeat our object. That an examination less 
stringent than our present Major in some respects, would effect this, we all 
know. 
Allow me to conclude by asking some of our members in the leading towns 
to give their fellow-members the advantage of a public expression of their opi¬ 
nions upon this important question. 
I have myself refrained from this publicity until now, but the serious mis¬ 
understanding of the question which has arisen from its having been so slightly 
brought before the body, has made me regard it as a duty to offer these expia¬ 
tions, with a view to clearing up some misconceptions. 
I am, Sir, yours truly, 
Leeds , December 22, 1863. It. Reynolds. 
INFUSUM CINCHONA SPISSATUM. 
Having lately had a considerable demand for this comparatively little-known 
preparation of cinchona, we have tried a few modifications of the process of 
the London Pharmacopoeia, which, in our opinion, produce a liquor contain¬ 
ing a larger proportion of the active principles of the bark, and yield a prepa¬ 
ration much superior, to that obtained by a strictly pharmacopical method. In 
the first place, with regard to the degree of comminution to which the bark 
should be reduced, the Pharmacopoeia directs that it should be employed in a 
coarse powder, which is certainly rather an indefinite term ; we have, however, 
with great advantage used a uniform powder produced by passing it through a 
sieve of about fifty meshes to the inch ; it is then mixed with distilled water 
(which should always be employed on account of the salts of lime ordinarily present 
in common water, which form a serious objection when the degree of concen¬ 
tration is taken into consideration) until formed into a paste after twenty-four 
hours’ digestion, during which time the greater part of the moisture is absorbed ; 
more water is added, until there is sufficient to completely cover the bark to the 
depth of an inch ; in this state it is allowed to remain for four days at a tem¬ 
perature of 55° to 60°, and stirred thoroughly at intervals; at the expiration of 
this time the liquor is strained off, the residue strongly pressed, more water is 
then added and macerated for two days, pressed, finally macerated again for 
the same period, and subjected to powerful pressure; the mixed liquors are then 
evaporated over a bath at a temperature of 170° until reduced to a specific gra¬ 
vity of about 1*200 : the setting aside of the liquors when partially evaporated 
to deposit the dregs, seems to be of very little importance or advantage, as we 
have found but a very trifling deposit in the liquor obtained by the above pro¬ 
cess. It will be seen that this mode of preparation occupies a period almost 
three times that of the Pharmacopoeia, and judging by the result, the length of 
maceration seems to be no greater than is absolutely required for the water to 
thoroughly permeate the woody fibres of the bark, and render it sufficiently 
soft to be influenced by the pressure to which it is subjected. The infusion we 
have noticed does not appear to require more than fourteen days for the dregs 
to subside, as it is generally perfectly bright even at the expiration of a week, 
but a longer time renders it less likely to deposit when bottled; the specific 
gravity of the liquor when reduced to the strength of one drachm, equivalent to 
