ON FRASERA WALTERI. 181 
tained from one ounce of the root. That prepared with dilut- 
ed alcohol in the same proportions, was of a redder color, but 
not superior in bitterness to the watery extract ; nearly three 
drachms of extract were procured by this process. 
My attempts to procure volatile oil by distillation did not 
succeed. The water, that came over, possessed but little bit- 
terness. 
This root is mentioned as an adulteration of the true Co- 
lumbo (Cocculus palmatus,) but may be distinguished from 
that drug by the want of concentric and radiating lines which 
mark the latter, and its pure yellow color without a tinge of 
green. It will be seen from the foregoing experiments, that 
iodine affords an excellent means of discrimination between 
these articles. If a fresh cut surface of each of these roots be 
immersed for a few moments in boiling water, and then touch- 
ed with iodine or its tincture, a blue compound will be form- 
ed with the Columbo, indicating the presence of starch, while 
the Frasera will not be affected in the least by this reagent. 
The difference in their specific gravity, may also serve to dis- 
tinguish them ; when thrown into water the Columbo im- 
mediately sinks to the bottom of the vessel ; the Frasera, from 
its greater levity, swims on the surface. 
From the preceding experiments the root of American 
Columbo may be supposed to contain Gum or Mucilage, Lime, 
Carbonate of Lime, Tannin, Gallic Acid, Resin, Fatty Matter, 
Sugar, a yellow coloring substance, Bitter Extractive, Lignin. 
