I Anahjfts of the Atr\ i p i 
i Calculus^ fliould rather encourage than dif- 
I courage us, iii fearching after fome proper 
j diffolvent of the Stone in the Bladder, which, 
upon the analyfis of it, is found to be well 
ftored with aftivt principles, fuch as are 
the principal agents in fermentation. For 
Mr. Boyle found therein a good quantity of 
volatile fait, with fome oil, and we fee by 
, theprefent Experiment, that there is ftorc of 
1 unelaftick air particles in it. The difficulty 
j feems chiefly to lay, in the over proportion 
] of thele laft mentioned particles, which are 
firmly united together by fulphur and fair, 
the proportion of caput mortmm-, or earth 
being very fmalh 
I Experiment LXXVIII. 
!i 
I One eighth of a cubick inch of Mercury 
|i fnade a very infenfiblc expanfion in diftilla- 
tion, notwithftanding the iron retort had 
I an almofl: melting heat given it, at a fntith's 
I; forge, fo that it made an ebullition, which 
could be heard at fome diftance, and withal 
(hook the retort and receiver. There was 
no air generated, nor was there any expan- 
fion of air in the following Exper. njiz,. 
O Expe- 
