It 6 On the Animal Calculus. 
Experiment VIIL 
TN the Hiftory of the Royal Academy of 
Sciences at Paris, An, 1720. there are 
Accounts of feveral Calculi being didolved by 
laying them many Days in Water, fooner or 
later according to their different Degrees of 
Hardnefs. 
I tpok fome of the abovementioned, afli- 
coloured, and round redifli Gravel Scones, and 
put fome of them at the fame time into cold 
and warm Water, and found thofe in warm 
Water diifolv’d much fooner than the other, 
they being covered with a white Mucus, 
3. I laid feveral Gravel Stones in a little 
Rill of warm Water for fourteen Days and a 
good part of thofe Nights: They had feveral 
of them a white Mucus over them j but they 
did not diflblve to faft as thofe in ftagnant 
warm Water ; the Reaton of which might be 
fhat this running Water was but half to warm 
as the abovementioned ftagnant Water ; and 
they were befides lome part of each Night 
cold, when the Water ceafed to run. 
4. I poured into a Plorence Flask thirty nine 
cubic Inches of Water, and one of frefli U- 
