250 ON THE VOLATILE OIL OF BETULA LENTA, ETC 
diminutive individual of the heath tribe, was indeed striking: 
now we have the same complex substance pervading the 
bark, leaves, &c. of one of the largest of our forest trees. 
Additional interest attaches to the latter because of a prin- 
ciple of a still more complex nature that exists in it, and 
which contains the elements of the salicylate of methylene; 
thus adding another to that class of neutral substances, of 
which amygdaline is the type. 
It will be interesting to know the ultimate composition of 
this principle, and the relation it bears to gaultheric acid 
and to salicylate of methylene. Before that can be accom- 
plished, the necessity of obtaining it in a pure state is impe- 
rative. The more important of the observations contained 
in this paper were made during the past spring and summer; 
but till recently the author has not had sufficient leisure to 
arrange them for publication. It is hoped that the attention 
of chemists will be attracted to these principles, and their 
character more fully developed, 
Dec. 20th, 1843. 
