242 
CINCHONA GROWN ON THE NEILGHERHY HILLS. 
living bark, and are most suggestive of future experiments in the cultivation of the 
latter. 
16. It has been stated that the action of the moss is to protect the alkaloids from 
oxidation. This is contradicted by the circumstance that moss does not exclude 
either air or oxygen. It is also incompatible with the fact that the quinidiue produced 
under moss in Micrantha bark is really a more oxidized substance than the cinchonine 
produced in the natural bark when fully exposed to the air. 
17. It appeared to me that an examination of bark that had been renewed by natural 
processes, without the application of moss, would possess considerable interest. It was 
suggested by a statement in Howard’s ‘ Nueva Quinologia of Pavon,’ and also given on 
the authority of Ruiz.* I was able to obtain a small quantity of such renewed bark 
from two Succirubra trees which had been injured and partially stripped of their bark 
by the falling of a log in October, 1864. The renewed bark was thicker than that of the 
natural bark, measuring 0T9 to 022 inch, instead of 0T6 inch, and had replaced 
itself mainly from the edges of the wound,—not from the surface, as is the case in 
mossed bark; but its analysis gave but 5 per cent, of alkaloids, of which about 3’25 ap¬ 
peared to consist of the cinchonidine and cinchonine. Unless, therefore, the effect had 
been impaired by the lapse of time or the character of the injury, the quality of this 
renewed bark does not appear to corroborate the statement I have had the honour to 
cite above. 
18. I would submit that the foregoing facts and considerations render it highly pro¬ 
bable that the exposure of the living bark to direct sunlight has the effect in diminishing 
the yield in alkaloids, and hence the advantage of direct protection. 
I would beg leave to defer a comparative estimate of the respective values of the 
three varieties of C. officinalis till a subsequent report. 
19. Analysis of the bark taken from a plant of C. lancifolia , two years old, yielded 
08 per cent, of alkaloids, in which (though but a very small amount of bark was at my 
disposal) I was able to obtain distinct traces of crystalline sulphate. 
20. An analysis of the trunk bark of C. micrantha of four and a half years old, yielded 
the following numbers, expressing percentages in dry bark:— 
Total alkaloids... 7T 
Alkaloid soluble in ether . 0-3 
Cinchonine . . 6 8 
Crystalline sulphates . None. 
This large amount of cinchonine, crystallized from solution in alcohol with the greatest 
readiness and purity, forming splendid crystals 0T8 inch long. Huanuco bark con¬ 
tains usually only about 2-0 per cent, of alkaloid. Should cinchonine come into use as 
a febrifuge (as appears not improbable from the experimental results of the Cinchonine 
Commissionf), this Micrantha bark will furnish a most easy and abundant source. The 
tree rivals C. succirubra in rapidity of growth, and the bark at present is 0T7 inch 
thick. It loses on drying 73 per cent, of water. 
21. Nearly all the above analyses were made with the fresh, undried bark of the trees. 
Some preliminary experiments showed me that the bark in the “ green ” condition pre¬ 
sented several advantages which facilitate its examination for alkaloids. The latter are 
extracted with far greater ease from the fresh than from the dried and powdered bark ; and 
with much less expenditure of acid and labour, and consequently with diminished risk of 
error or alteration in composition. I am of opinion that this property of the fresh bark will 
eventually become of considerable importance. For purposes of quotation, it is of course 
indifferent whether the analyses are conducted with the fresh or the dried bark, provided 
the process of drying be conducted with proper care. 
22. I have communicated these and other results of my observations to Mr. MTvor. and 
have discussed with him various applications to future cultivation. I have had to thank 
Mr. MTvor for much kind assistance, and also for some valuable information concern¬ 
ing the plantations and their products. 
* ‘Nueva Quinologia,’ C. TJritusinga, p. 3.—“They cut off (Don Riopio told me) the whole 
of the bark of the trunk of a small tree, leaving only a broad strip, so as not to destroy the tree, 
which gradually replaces its loss ; and the second time of cutting the bark is called cascarillas 
resecatas, and esteemed of superior quality.” 
t Proceedings of the Madras Government, No. 302 of 1867. 
