304 
ORIGINAL COMMUNICATIONS. 
(hyduret of benzule) has no sensible effect on the aninrial 
economy, other than the disgust manifested at the disagreeable 
taste; and, from the activity of the former, this acid must 
exist in considerable quantity. 
From the foregoing statements, it appears evident that the 
oil of the Prunus Virginiana is very nearly identical with 
the oil of bitter almonds; for not only is this the case in its 
sensible and toxicological properties, but in its chemical com- 
positions. LiEBiG and Wohler state, that neither the oil 
nor its accompanying acids pre-exist in the ajmond ; and, if 
not, the question arises in what state does the benzule and 
cyanogen exist in the almond, and, consequently, in the bark. 
The recent almonds, as also the bark, possess the odour of hy- 
drocyanic acid, but when dry, are entirely void of it; hence we 
are led to the opinion that benzule and cyanogen do reside in 
the bark, but in what state of combination we are unable to 
say. Benzule has never been obtained in a free state, hence 
we know nothing of its properties as an isolated substance. 
But as it is possessed of considerable permanence, and may 
possibly be entirely void of odour, it may exist in com- 
bination with some substance, other than hydrogen, in the 
dry bark, which compound may not have any aroma. 
Therefore, the most plausible theory is, that benzule and 
cyanogen do pre-exist in the bark of the Prunus Virginiana, 
which, by the decomposition of water, are converted into 
benzoic acid and hyduret of benzule, on the one hand, and 
hydrocyanic acid on the other. 
