° 
PRODUCED BY DISTILLATION OF CINCHONINE. 311 
idea which often forced itself upon me, namely, that there might be some basic 
product besides pyrrol, characteristic of the destructive distillation of nitrogenized 
organic bodies, because I had no decisive proof; but I may mention that there is 
a most intimate connection between the volatile bases best known, produced at 
very high temperatures. For with all the substances as yet examined, such as 
bones, shale, &c., the complete series of bases homologous with pyridine has been 
found, and though, in the case of coal naphtha, only picoline has as yet been de- 
tected, I believe I shall shortly be able to prove, that other members of that series 
exist in it. It will be seen that, if these views are correct, indigo and piperine 
ought to yield more than aniline in the one case, and piperidine in the other, 
which, in the present state of our knowledge, does not appear to be the case; 
while, on the other hand, if we study the experimental results yet obtained 
from coniine, it will scarcely be too much to conclude that it is a mixture. 
In order to give a decisive answer to the question raised by these facts, it be- 
comes necessary to examine, somewhat minutely, several of the bases said to be 
the sole product of the destructive distillation of certain alkaloids, and other nitro- 
genous bodies ; and the following may be regarded in the light of a small contri- 
bution to the subject. 
It being evident that a considerable amount of material would be required, I 
subjected 100 ounces of cinchonine to destructive distillation with potash, by 
small portions at a time, in an iron alembic, the products being collected in a well 
cooled recipient, but notwithstanding the large scale on which the experiments 
were carried on, some difficulty was found in procuring enough of certain portions 
for examination. 
There were several phenomena observed during the preparation of the crude 
chinoline, which are not described in the works to which J have had access; but 
as these are not immediately connected with the subject under consideration, 
they need not be further alluded to, except to mention that whatever precautions 
were taken in the distillation, pyrrol was, nevertheless, constantly found, and ad- 
hered to the crude chinoline with such tenacity, that it required two days’ boiling 
of the acid solution to effect its complete removal. 
The base was separated from the simultaneously-produced water, by means 
of caustic potash, which was added in sufficient quantity to prevent any remain- 
ing dissolved. After separation, by means of a tap funnel, from the dense alkaline 
solution, it was again digested with sticks of the potash, until no more water was 
removed. The general process for separating these volatile bases from non-basic 
and other impurities, has been so often described, that it becomes unnecessary to 
dwell upon it further. 
On distilling perfectly dry chinoline, with a thermometer in the tubulature of 
the retort, ebullition was found to begin at about 300° F. (149 C.), although no 
* I have inserted the centigrade degrees (in round numbers), for convenience of those accustomed 
to that scale. 
