REVIEWS. 
657 
bark. From this single specimen sent out to India, thousands of plants hare been 
reared. This percentage has, however, been excelled by Indian-grown bark, yielding 
10 per cent, of quinine, as analysed by Messrs. Broughton and Howard.* 
The effect of sunlight on the Cinchona is very remarkable. Of “ red bark,” grown 
under dense shade, the proportions were sulphate of quinine T48, cinchonidine *61, 
cinchonine 2‘54. Of bark from trees of the same age, but grown in full sunlight, the 
analysis afforded on examination was sulphate of quinine 2 35, uncrystallized quinine 
‘95, cinchonidine 1 11, cinchonine *58 ; the quinine in the latter being doubled, and 
the cinchonidine much reduced. 
The first trial importations of bark from India took place in August, 1867, consist¬ 
ing of bark of Cinchona succirubra, yielding Dr. De Vrij 6‘8 per cent., 2‘85 being qui¬ 
nine, and the remainder mostly cinchonidine. Two small chests of bark of C. succi¬ 
rubra and C. officinalis, of only three years’ growth, reared in Ceylon plantations, was 
sold by public auction in April, 1868, in London, and commanded a higher price than 
South American barks of the same age and species, being found richer in alkaloids 
than the latter. But the growth of the Cinchona is slow, and cultivators would have 
had to wait a long time before any return could be expected on their capital but for 
the happy idea of Mr. MTvor of “ mossing the bark,” by which means partial decor¬ 
tication can take place without injury to the tree. Mr. MTvor thus describes his 
process :—“ In removing the strip of bark, two parallel cuts should be made down the 
stem, at the distance apart of the intended width of the strip of bark ; this done, the 
bark is raised from the sides of the cut and drawn off, beginning from the bottom ; 
care being taken not to press or injure the sappy matter (cambium) left upon the stem 
of the tree. This cambium, or sappy matter, immediately granulates on the removal 
of the bark, and being covered, forms a new bark, which maintains the circulation un¬ 
disturbed.” 
Next follow remarks on the cambium layer, and mode of renewal and origin of the 
renewed bark. If a piece of bark be stripped off carefully, and the decorticated wood 
preserved from desiccation and atmospheric influences—by moss, for instance,—the 
cambium exudes in small drops, gelatinous in appearance and consistence; these become 
hardened into a new bark of a very perfect development. These renewed barks are 
found to yield an alkaloid in greater abundance and purity than the original. There 
has been much discussion with respect to the seat of the alkaloid. Mr. Howard and 
Mr. Broughton find that it is contained in the largest proportion in the cortical por¬ 
tion of the bark, and not in the liber or fibrous portion. Thus the inside portion of 
the bark of Cinchona succirubra yielded 4‘29 per cent., whilst the outer cortical por¬ 
tion yielded 10 66 per cent. Mr. Broughton gives the proportions of the inner and 
outer portions as 3 to 5. Not only light and air affect the production of the alka¬ 
loids (shade favouring the production of quinine, and the former einchonidine), but 
it is found the alkaloidal yield varies with the seasons, the maximum yield being be¬ 
tween the beginning of February and end of March. 
As to the final suecess of the acclimatization, Mr. Howard is of opinion that by 
avoiding errors in the elioice of species, and by carefully selecting the best situations 
and modes of culture, individual planters in other parts of the world will see their 
efforts crowned with remunerative results. 
Though the Crown barks are more difficult to adapt to altitudinal situation, and a 
third less rapid in growth than the red bark, yet they are found to be the most valu¬ 
able, yielding, as they do, quinine in greater purity, and free from the resin so difficult 
to get rid of in the “ red bark.” 
The plates consist of 23 figures of the microscopical appearance of red and Crown 
barks, beautifully drawn and coloured by Mr. Tuffen West, the well-known artist. 
Plate 1 represents bark of C. succirubra, showing the effect of growth in dense shade, 
which favours suberous growth ; in sunshine and under moss, the latter being remark¬ 
able for the quantity of alkaloid in situ. Plate 2 consists of figures of “ renewed 
bark and plate 3 of the third crop of renewed red bark, and of unrenewed and re¬ 
newed quills of C. officinalis. One histological feature we notice with considerable 
interest in this plate, is the existence of scalariform tissue in the renewed red bark. 
Mr. Howard very conveniently sums up the conclusions he has deduced from the 
* Pharmaceutical Journal, vol. x. p. 624, second series. 
