C I0 3 ] 
weighed again, and found to be perfectly equal, each 
having gained fix grains of additional weight. 
Ob. The common practice of prolonging the in- 
fulion to three days at leaf!;, is always tedious, fre- 
quently inconvenient, and, if we may truft this experi- 
ment, not neceffary, becaufe not ufeful, fince the 
menftruum appears to have been as fully impregnated 
after one day’s infufion, as after three. 
Experiment XXV. 
Three parcels of the fame powdered bark were put, 
with fix ounces of water to each, to infufion at the 
fame time. After twelve hours the firffc was filtered, 
the fecond after twenty four, and the third after lix and 
thirty hours infufion. The filtered liquors were not 
difcernibly different in colour and tafle, nor in a 
refiduum obtained from each, as in Experiment 24, 
was there any perceptible inequality on the fcale. 
Ob. This experiment may diredt our pradtice in 
preparing the cold watery infufion with more precifion 
than is commonly known. I apprehend too, that it 
may further ferve to amend our pharmaceutical prac- 
tice in many other fimilar points, in which our vene- 
ration for the antients has induced us to acquiefce in 
their forms, which they did not found upon experi- 
ment, the only admiftible teft of their propriety. 
Thefe are all the pharmaceutic experiments I have 
hitherto made on the Peruvian bark ; they were 
intended as a part of a com pleat hiftory of this medi- 
cine, which, though almoft finifhed, an unexpected 
and indifpenfable call into my own country, prevents 
me from making public. I will juft beg leave to 
fubjoi'n a remark, concerning the tindture of the bark 
‘ with 
