On the Animal Calculus. 235 
^ths of a cubic Inch of this Incmftation I ob- 
tained by Diftillation three hundred and 
twenty four cubic Inches of Air, of which 
one hundred and eighty loft their Elafticity 
in four Days. 
y. And from a like Quantity of the much 
harder Incruftation of the New River Water 
there arofe in Diftillation two hundred and 
thirty four Cubes, of which in four Days a 
hundred and eight loft their Elafticity. 
6. The Air arifes much flower from thefc 
Subftances in Diftillation, than from the Tar- 
tar of Wine or from the Calculus Humanus^ 
for which reafon a longer Continuance of an 
intenfe Degree of Heat is requifite. 
7 . From three hundred and twenty eight 
Grains, or about half a cubic Inch of the 
powdered Incruftation of boiled Well Water, 
let fall on two Cubes of Spirit of Salt, there 
arofe eighty one cubic Inches of Air, all which 
loft its Elafticity in feven Days. 
8 . Three hundred and twenty eight Grains 
of the laft mentioned Incruftation, with two 
Cubes of Oil of Sulphur, generated two hun«» 
dred and fixteeft Cubes of Air, all which did 
alfo Igfe its Elafticity in feven Days. 
Q. The 
