DRAGON ROOT. 55 
application of the root to his mouth, Its action 
does not readily extend through the cuticle, since 
the bruised root may be worn upon the external 
skin until it becomes dry, without occasioning 
pain or rubefaction. 
The acrid property, which resides in this and 
other species of Arum, appears to depend upon 
a distinct: vegetable principle in Chemistry, at 
present but little understood. It is extremely 
volatile, and disappears almost entirely by heat, 
drying, or simple exposure to the air. I have en- 
deavoured, with but partial success, to obtain it 
in a separate state, orin any perceptible combina- 
tion. The following were some of the methods 
by which it was attempted. 
Portions of the fresh contused root were sepa- 
rately digested in water, in proof spirit, in alcohol, 
in ether, in olive oil and in vinegar. The infu- 
sions were tasted at different periods, but none of 
them had acquired the least acrimony from the 
plant. 
The expressed juice of the root upon standing 
one minute had lost all its pungency. 
A quantity of the bruised root was placed in a 
retort and covered with water. Heat was gradu- 
ally applied, until a fluid began to collect in the 
receiver. This fluid had the peculiar odour of 
