3 11 
received have contained residues varying from 0*1 to o' 6 per cent. 
This variation would be expected, when the empirical manner in 
which the drug is prepared, and the variation in the age of the 
leaves and the amount of extractive matter taken from them in 
the process of boiling, is taken into consideration. 
Preliminary observations have not shown the presence of 
any alkaloidal, glucosidal or other bitter principles. The organic 
matter consists principally of tannin, which is probably the active 
constituent, but I have been unable to estimate the latter owing 
to lack of apparatus and chemicals till recently. The explanation 
of the physiological action of the drug as an anti-opium cure is 
somewhat difficult. Tannin is a precipitant of morphing and 
other opium alkaloids, but very small quantities of these alkaloids, 
if any, are absorbed into the system when opium is smoked. The 
effect of the drug on an opium eater might be as a precipitant of 
the alkaloids in the stomach before absorption, thus rendering 
them insoluble. If this explanation is valid, any other tanning 
solution, e.g ., strong tea, or solution of gambier, cutch, etc., 
might be substituted for this drug. 
Hydrocyanic Acid in Plants. 
Some preliminary experiments have been carried out to 
ascertain whether the cyanogenetic glucoside known to be present 
in the seeds of the Para rubber plant ( Hcvca braziliensis ) was also 
present in the leaves and other parts of the plant. 
Leaves and twigs were examined separately by maceration 
in cold water and by hydrolysis with dilute mineral acids. In 
each case, appreciable quantifies of prussic acid were obtained 
from both leaves and twigs by decomposition of the glucoside, 
one specimen yielding o*o8 per cent, of prussic acid. The plants 
from which the leaves were obtained were planted in 1905. 
It is proposed to continue the experiments with young plants 
of different ages, to ascertain the variation in the amount of 
glucoside at different stages in the plant’s growth. 
These glucosides have now been Insolated from a number of 
plants, and their presence indicated by the production of prussic 
acid hydrolysis from many other plants from which the 
glucoside have not yet been actually isolated. 
An excellent resume of the subject is given in the “ Bull., 
Imperial Institute,” Vol. IV, No. 4, 10,06, which contains the 
valuable investigations of Dunstan and Henry and of Treub. 
B. J. EATON, 
Government Chemist , F.M.S. 
