114 
Original Communications. 
added to the solution caused a white flocculent precipitate. 
On adding a solution of phosphate of soda, no change was ob- 
servable, but when ammonia is added, a white precipitate was 
immediately produced, which led to the belief that a salt of 
magnesia was present. 
From the result of these few and imperfect experiments we 
may venture to enumerate the following, as among the prin- 
cipal constituents of the Cornus Florida. 
1, Gum. 2, Resin. 3, Tannin. 4, Gallic acid. 5, Oil. 
6, Fatty matter. 7, A crystalline substance. 8, Bitter extrac- 
tive. 9, Wax. 10, Red colouring matter. 11, Lignin. 
12, Potassa. 13, Iron. To which may be added salts of 
lime and magnesia. 
It will be seen that these experiments have not led me to 
any decided conclusion as to the nature of the active princi- 
ple of Cornus Florida, or the form in which it exists in the 
bark. The peculiar bitterness of the bark, seemed to be de- 
veloped to a considerable extent, in the etherial extract : but 
more fully in the bitter extractive, than in any other form 
that came under my observation. Dilute alcohol appears to 
be the best solvent. 
The bark was also treated by several other processes, but 
with no satisfactory results ; which were not deemed of suf- 
ficient importance to be mentioned in this place. 
