Cornus Florida* 
The tincture was poured off and treated with animal charcoal 
and when evaporated left a brown extract of a resinous waxy- 
appearance, and very bitter taste, which appeared to have 
very much the flavour of Peruvian bark; this was again treated 
with animal charcoal and left, on evaporation, a crystalline 
mass in an impure form, which was slightly soluble in alcohol, 
almost insoluble in ether, but very soluble in nitric acid. The 
alcoholic solution was evaporated and left crystals of a very 
fine, long, flexible, and silky appearance : which crystals de* 
composed when thrown upon red coals, and did not form a 
precipitate with oxalate of ammonia, but were without taste. 
The bitterness was entirely owing to the bitter extract, 
Which was slightly soluble in water, soluble in alcohol, but 
nearly insoluble in ether. This I propose to call bitter extrac* 
live, and in this I am inclined to believe the active principle 
resides. 
A concentrated tincture yielded by evaporation a dark 
brown extract slightly soluble in water, soluble in alcohol and 
ether, bitter aromatic taste, possessing the properties of resin* 
Both this and the watery extract possess the sensible proper- 
ties of the bark in a concentrated form. 
There is a red colouring principle in this bark, taken up 
very feebly by alcohol and ether, but less so by water, and 
has its colour rendered deeper by an alkali. 
One thousand grains of the bark yielded, by incineration, 
a product weighing sixty-five grains : this residue was sub- 
mitted to the action of boiling water, and concentrated by 
evaporation : it then had an alkaline taste, effervesced strongly 
with acids, and restored the blue colour to litmus, previously 
reddened by an acid ; it was then neutralized with nitric acid, 
and upon evaporation yielded crystals of nitrate of potassa. 
The insoluble residue of the preceding experiment, was 
dissolved by nitric acid, (with the exception of a minute por- 
tion of carbonaceous matter,) with violent effervescence ; the 
colourless solution thus obtained threw down a white precipi- 
tate on the addition of oxalate of ammonia, and a deep blue 
one with ferrocyanate of potassa. It produced also a dark 
green or black with tincture of galls. Carbonate of soda when 
Vou I—No. 2 15 
