IN THE CURE OF THE STONE. 425
■which they are immerfed in different menßruums be alfo equal, the
powers of the menßruums will be directly as the quantities diflolved.
If the weights and quantities diflolved be equal, the powers of
the menßruums will be inverfely as the times during which the calculi
were immerfed.
If the quantities diflolved, and times of immerfion of two fimilar
pieces of the fame calculus be equal, the powers of the menßruums
will be inverfely as their furfaces, and confequently as the fquares
of their diameters, or the fquares of the cube-roots of their weights.
Therefore, when the times, weights, and quantities diflolved
are unequal, the powers of the menßruums will be directly as the
quantities diflolved, and inverfely as the times and fquares of the
cube-roots of the weights of the calculi. Thus, fuppofing M, m, to
be the power of the menßruums, Q^q, the quantities, T, t, the times,
„ 2 , n
and W, w, the weights of the calculi ; then M : m : : cl* tXw^ : H
x T x \W*
If the fame menßruum be employed in diflfolving fimilar pieces of
different calculi, when the calculi are of the fame hardnefs, the times
required to accomplifh their toçal diflblution will be diretflly as their
diameters. When the diameters are equal, the times will be dire<£l-
ly as the hardneffes. Wherefore calling H, h, the hardneffes, T, t,
the times of total diflblution, and D, d, the diameters. T : t ; ; D
t . _t_ _T t
x H : d x h. Whence H : h : : d d i. e. _3 : 3_
yw a/w
TABLE.
Dißolving
Menßruums. powers.
Stone lime-water, experiment 11. - - 100
Strong (lone lime-water, exper. 12. - * 130
Oifter-fhell lime-water, exper. 16. - - 296.
Stone lime-water in cold digeftion in the month of May,
exper. 13. - - 49
Hhh Oifter-