PRICKLY ASH. : 459 
green and dried bark. The water in which the 
bark is boiled has a peculiar pungent heat, which 
is not perceived when the liquid is first taken 
into the mouth, but gradually developes itself by 
a burning sensation on the tongue and fauces. 
It retains this acrimony after standing a week 
and more. The leaves do not appear to possess 
the pungency of the bark, and impart no acri- 
mony to the water in which they are boiled. 
They abound in mucilage, which coagulates in 
large films when alcohol is added to the decoction. 
They seem to possess more astringency than the 
bark, and strike a black colour with sulphate ‘of 
iron, while solutions, made from the bark, are but 
moderately changed by the same test. The 
alcoholic tincture of the bark is bitter and very 
acrid. Its transparency is diminished by adding 
water, and after standing some time it becomes 
yery turbid. Whether the acrimony of this 
shrub resides in a peculiar acrid principle, or 
whether it belongs to the resin and becomes 
miscible with waterin consequence of the presence 
of mucilage, may be considered as yet uncertain. 
The Prickly ash has a good deal of reputa- 
tion in the United States as a remedy jn chronic 
rheumatism. In that disease its operation seems 
analogous to that of Mezereon and Guaiacum, 
