On the A 7 mnal Calculus. 203 
kalinc Mixture, by pouring in of the ftrongeft 
acid Spirits, as Spirit of Nitre, Spirit of Salr^ 
Spine and Oil of Vitriol, and Oil of Sulphur. 
1 found Oil of Vitriol and Oil of Sulphur moft 
j effeftual to my Purpofe, and of thefe two, I 
chofe rather to make life of Oil of Sulphur 
than Oil of Vitriol, as being the purer Acid 
of the two, and lefs noxious to ajaimal Bo*r 
dies than Oil of Vitriol. 
2. I found after the Mixture of a great 
Variety of Proportions of thefe Liquors, that 
the following were the propereft for my Pur- 
pofe, njiz. one cubic Inch of Water, one 
third of a cubic Inch of Solution of Sal Tar* 
tar^ and twenty five or fometimes thirty Drops 
I of Oil of Sulphur. Alfo fix cubic Inches of 
Water, ^ Cub. of the Solution of Sal Tartar^ 
and fifty Drops of Oil of Sulphur. 
5. Thefe Proportions fermented briskly, 
and made Air Bubbles arife very faft from the 
I Calculi for eight or ten Minutes, as would 
alfo feveral other Proportions, tho* I did noc 
find any fo effedual as thefe, which after fe- 
yeral frefli Aff'ufions of them, would diflblve 
fomc Calculi which were hard to the Touch : 
I They would alfo dillblve feveral Gravel Stones, 
tho* noc all ; nor had they any Efteft on ma- 
ny of the hardefi: Calculi. If 
