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Received February 5th, 1767. 
. ... f . . 4; * 
XXVI. Experiments on the Peruvian Bar% 
by Thomas Percival, M. D. F. R. S . 
I ■» t * . *■ 1 - r\\ vr; 
Experiment I. 
Read March y* N ounce of Bark coarfely powdered 
7, 1767. was divided into two equal parts, one 
of which was infufed forty- eight hours in cold fpring 
water ; the other was boiled over a flow fire forty 
minutes, until about a third part of the water was 
evaporated. The infufion and decodtion were each 
filtered through linnen rags doubled and of equal 
finenefs. 
Four grains of Sat Martis were diflolved in an 
ounce of fpring water, and one dram of this folution 
was added to equal quantities, viz. half an ounce ; of 
the turbid decodtion and infufion. Each affumed a 
deep purple colour, fcarcely perceptibly different in 
degree ; though I thought the infufion, after handing 
a while, acquired rather a more dufky purple than the 
decodtion. 
The infufion had a deeper tinge, and more of the 
tafte and fmell of the Bark in fubftance than the de- 
codtion. Its tafte indeed exadtly refembled the Bark, 
after it had been broke down and chewed for fome. 
time in the mouth. 
Expe- 
