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I. I put a piece of a very hard calculus , which 
I lhall call x , weighing 80 grains, in oyfterfhell 
lime-water, renewing the lime-water every day, and 
keeping it in a heat between 90 and 1 06 degrees of 
Fahrenheit's fcale. After 20 days, I took out the 
calculus ; and having fet it by for fome days, till it 
was become quite dry, I brufhed away all the rotten 
part of it, which was reduced to a kind of chalky 
powder, and found that the undiffolved part of it 
weighed 57 grains. 
1. At the fame time a piece of another calculus , 
weighing 1 y grains, was, after a like infufion of 
20 days in oyfterfhell lime-water, reduced to 10 
grains. 
3. I put a piece of weighing. 14 grains, in a 
folution of half an ounce of the internal part of 
Spanifh foap in nine ounces of water, and every 
third day renewed the folution, which was kept in 
a heat of about 60 degrees. After 14 days, I found 
the undiffolved part not to exceed 1 1 grains. 
4. A piece of a white chalky calculus , y, weigh- 
ing 30 grains, had near 4 grains of its fubflahce 
diffolved, by being 14 days infufed as above in a fo- 
lution of foap. 
From N°. r. above, compared with Dr. Springs- 
feld’s Exper.(B), it appears, that the diffolving power 
of oyfterfhell lime-water is to that of the Carhbad. 
water as 23 to 18, fuppofing the calculi ufed in thefe. 
experiments to have been equally eafy to diffolve. 
N°. 3. compared with Dr. Springsfeld’s Exper.(A), 
fhews, that the diffolving power of a folution of the 
inner part of Spanifh foap, in a heat of 60 degrees, 
