THE EIGHTH REMITTANCE OF BARK FROM INDIA. 
317 
luctantly compelled to desist making any farther attempts to arrive at the end 
we had in view, at least for the time, but we never lost the hope of resuming 
our investigation under more favourable circumstances. In an investigation of 
the nature of the present, it is evident that wrong steps must be checked by 
using the human frame as a medium for testing the existence of a cathartic 
power in any product. In consequence of this constantly recurring necessity and 
the difficulty of getting or-asking another person to submit to the, at least dis¬ 
agreeable, ordeal, we were led to dose ourselves to such an extent as to bring on, 
in one of us, a state of irritation of the whole mucous membrane of the 
alimentary canal, extending even to the nostrils, and the effects of which 
have not disappeared even to this day, so that we were compelled to throw aside 
the whole investigation, and it affords us much pleasure to see that it has been 
taken up and so well wrought out by others. 
REPORT OF AN ANALYSIS OF THE EIGHTH REMITTANCE OF BARK 
FROM INDIA. 
BY J. E. HOWARD, F.L.S. 
To the Under Secretary of State for India. 
September ls£, 1868. 
Sir,—I have to report on specimens of bark collected in March of the present year, 
and sent to me for analysis, as follows :— 
No. 1 , C. succirubra, being the “ third harvest of renewed bark,” is most interesting, 
as it showed more completely than any sent hitherto the aspect of the red bark from 
South America, and has, in all respects, a superior appearance. In examining it chemi¬ 
cally, I found that it presented also more exactly the counterpart of that composition 
which I have described as being commonly observed in the analysis of the older bark of 
this species. I hoped to obtain a larger produce than last time, but was disappointed in 
finding a smaller amount of salts of quinine, viz. 6-15 per cent, against 8*45 per cent, 
in the specimen of renewed bark from the same tree on which I had the honour to 
report in February, 1867. 
The above figures give the relative commercial value of the two specimens; but, as 
I thought it desirable to obtain all the information in my power, I endeavoured, in two 
experiments, with a sufficient quantity of bark lb.) in each, to arrive at the most 
correct results. From the first I obtained quinine as alkaloid, capable of being formed 
into, and equivalent to 5*33 per cent, of sulphate of quinine. From the second, by a 
process somewhat varied, I obtained in crystallizations of refined oxalate 4‘80 per cent., 
and remaining in the liquor as more soluble (in part, perhaps, oxalate of cinchonidine) 
060, together 5'40 per cent, oxalate of quinine. In both cases there was an inevitable 
loss through the product being more exactly purified, and therefore this must be borne 
in mind in comparing these figures with those previously given ; but, even at this lowest 
or minimum scale of production, the results are really surprisingly good, though not 
equal to the hopes entertained by Mr. M‘Ivor. 
The explanation of a smaller produce of sulphate of quinine appears to me to be found 
in the idiosyncrasy of this particular species, which I have described to the best of my 
power in my ‘Illustrations of the Nueva Quinologia,’ sub voce C. succirubra. 
I am pleased to find that Mr. Broughton, in his first report, corroborates what I have 
said as to the difficulty of obtaining the alkaloids in a pure state from this species, a 
difficulty which increases with the age of the tree. On this account I must again urge 
the necessity of carefully ascertaining what species are likely to yield the best permanent 
results. 
The precipitated hydrated alkaloids, in a subsequent examination, of a small portion 
of the present bark against a re-examination of a portion remaining from the second 
harvest, gave me for the second harvest of renewed bark— 
