36 
APPENDIX. 
E. (Page 29.) 
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 1st, 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. sucdrubra , 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 
chemically, 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 (J 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*38 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) 0*60, 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. MTvor. 
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 f Illustrations of the Nueva Quinologia/ sub voce C. sucdrubra. 
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-examina- 
tion of a portion remaining from the second harvest, gave me for the second harvest of renewed bark, — 
Alkaloids dried at the temperature of the air .... 10*60 
Of which soluble in ether, quinine, etc. . . . 8*70 ^ 
,, „ insoluble in ether, cinchonine, etc. . . 1*90 3 
For the third or present harvest of renewed bark, — 
Alkaloids dried at the temperature of the air 
Of which soluble in ether, quinine, etc. 
,, ,, insoluble in ether, cinchonine, etc. 
. 11*20 
9*40 } 
1*80 3 
It will be seen that the proportion of alkaloid has increased, but this would be no guide to the commercial value, which is 
almost entirely regulated by the proportion capable of being converted into crystallized salts. More valuable commercial informa- 
tion, consequently, will be gained from the following corrected analysis : — 
Quinine (as sulphate) . . . 5*33 
„ uncrystallizable . . . 2*00 (?) 
7*33 
Cinchonidine . . . . . • 1T4 
Cinchonicine . . . . . .0*53 
9*00 
I have attached a (?) to the weight of the proportion of uncrystallizable quinine, which it was impossible to ascertain exactly 
from so small a quantity of bark. Moreover, from its great implication with resinous colouring matter, I am led to doubt the 
possibility of obtaining any part of it as crystallized sulphate of quinine on a large scale. This uncrystallizable portion is, therefore, 
unimportant, and not to be reckoned, from a commercial point of view, as possessing any value to the purchaser of such bark for 
manufacturing purposes.* 
The analysis of No. 2, “ Root bark from a tree of C. sucdrubra seven years old,” presented much interest, as bearing on the 
question as to which of several modes of cultivation is to be preferred, since it has recently been proposed to cultivate the plant, 
like madder, solely for the roots. 
I consequently have forwarded about half the sample of No. 2, and also No. 3 (of which a very small quantity was sent from 
India) to Dr. de Vrij, as it was desirable thus to arrive at a consentaneous agreement on the value of the root bark, which I have 
always regarded unfavourably, judging from the root bark of the C. Calisaya, var. Josephiana , occasionally found in the market. 
* The weight of the crystallizable, and consequently more valuable, portion, was ascertained by the following process The 6*15 per cent, (as above) 
having been precipitated, the precipitate was dissolved in ether, separating thus the cinchonidine and the quinine, then dried at 212° F. It must be 
understood that quinine thus obtained from the C. sucdrubra , although sufficiently pure to pass the tests required in commerce, retains some cinchonidine, 
which can be separated by solution in acid and subsequent treatment with iodide of potassium. 
