\6'1 PHILOSOPHICAL TRANSACTIONS. [aNNO 1757. 



awav all the rotten part of it, which was reduced to a kind of chalky powder, 

 and found that the undissolved part of it weighed 57 grs. — 2. At the same time 

 apiece of another calculus, z, weighing 15 grs. was, after a like infusion of 20 

 days in oystershell lime-water, reduced to 10 grs. — 3. He put a piece of z, 

 weighing 14 grs. in a solution of -|- an oz. of the internal part of Spanish soap in 

 g ounces of water, and every 3d day renewed the solution, which was kept in a 

 heat of about 6o degrees. After 14 days he found the undissolved part not to 

 exceed 11 grs. — 4. A piece of a white chalky calculus, y, weighing 30 grs. had 

 nearly 4 grs. of its substance dissolved, by being 14 days infused as above in a 

 solutvon of soap. 



From N° 1 above, compared with Dr. Springsfeld's exper. (b,) it appeared, 

 that the dissolving power of oystershell lime-water, was to that of the Carlsbad 

 water, as 23 to 18 ; supposing the calculi used in these experiments to have been 

 equally easy to dissolve. — N° 3, compared with Dr. Springsfeld's exper. (a) 

 showed, that the dissolving power of a solution of the inner part of Spanish 

 soap, in a heat of 6o degrees, was to that of the Carlsbad water in a heat of 96 

 degrees, as 15 to 14. — From N° 4, compared with (a) the dissolving power of 

 soap was to that of the Carlsbad water, only as 4 to 6 ; but it was probable, that 

 had the solution of soap been kept in a heat of 96 degrees, its dissolving power 

 would, even in this experiment, have nearly equalled that of the Carlsbad water. 

 It should perhaps be observed, that a piece of the white chalky calculus of 

 N° 4 was not in the smallest degree dissolved by lying in lime-water 20 days. 



5. In exper. 19 of his essay on the virtue of lime-water, apiece of a calculus, 

 b, weighing 31 grs. lost 7 grs. by being infused 36 hours, in a heat of above 

 100 degrees, in very strong oystershell lime-water. And in the same water, of 

 a moderate strength, another piece of b lost, in the same time, 5 grs. — In this 

 last experiment, the lithontriptic virtue of lime-water appeared to be stronger 

 than in N° 1 and 2 above ; and greatly exceeded that of the Carlsbad water in 

 Dr. Springsfeld's exper. (a) and (b). 



But although, from what had been said, it appeared not only that lime-water, 

 but also a solution of soap, dissolved the stone in close vessels as fast, nay faster, 

 than the thermae Carolinae ; yet these last vvaters, when the calculi were so 

 placed in open vessels, that the water from the fountain might constantly flow 

 along them, effected a much quicker dissolution than lime-water, or even soap- 

 lee, or indeed any known menstruum, except perhaps strong spirit of nitre: for, 

 in the first experiment made by Dr. Springsfeld, a calculus of 2 and ^ oz. was, 

 in this manner, quite dissolved in 6 days. From this experiment, compared 

 with that of Dr. Springsfeld mentioned above (b), it will be found, on calcula- 

 tion, that the dissolving power of the Carlsbad water, when it is allowed to flow 

 constantly from the fountain along the stone, is nearly 39 times greater than 



