Cn SS 
PHYSICAL ann LITERARY. © 975 
/(b) 1 poured upon go grains of calcined oi. 
fterfhells, newly taken from the fire,- and re- 
duced toa powder, 96 ounces, or. five hun- 
dred and twelve. times their weight of ' boil- 
ing water. After g2 hours, during: which 
time. the infufion was frequently ftirred and 
fhaked, I decanted off the clear water, and 
filtered it'thro’ a piece of avery thick linnen- 
cloth doubled; by which means it was ren- 
dered free of any crufts, and equally pellu-. 
cid with fountain-water. With this. lime- 
water I filled the above vefel,; and found its 
- weight to be 25356. grains*. 
(c) Monpay, at feven in the evening, I, 
poured upon a pound of calcined oifterfhells,, 
frefh from the fire, ten times their weight 
of water; next morning at ten I decanted 
off the clear lime-water ; and having filtered 
ae : it 
altho’, in weighing fluids with this. veffel, one might err fix 
times more than this, yet it would not affect the point we. 
have in view, which is: not to determine with the greateft 
accuracy the different fpecific gravities of different lime- 
waters, but ov/y to thew that they are different. 
* The oifterfhells made ufe of in this, and the following 
experiments, were got from among the rubbifh on the fouth 
fide of the Caftle of Edinburgh, and were 8 free of any 
fea falt. 
