PHYSICAL AND LITERARY. 4^3 



balance, found it weighed 25' 3 26 Troy 

 grains ,*, befides the weight of the veflel 

 itfelf, which amounted to 13055 grains, 

 • (h) I poured upon 90 grains of calci- 

 ned oifter-fliells, newly taken from the 

 fire, and reduced to a powder, 96 ounces, 

 or five hundred and twelve times ibeic 

 weight of boiling water. After 92 hours, 

 during which time the infufion was fre- 

 quently flirred and fliaked, I decanted ofF 

 the clear water, and filtered it through a 

 piece of a very thick linen-eloth doubled ; 

 by which means it was rendered free of 

 any crnfts, and equally pellucid with 

 fountain water. With this lime-wat^r, I 



fiffed 



* According to VTr Cray's experiments, the water 

 which this vefTel contains, only weighs 23518 

 grains, i. e, two grains lefs than we have made it, 

 This difference may have arifen from our having^ 

 put a few more drops of water into the veffsi than 

 Mr Gray did. But although, in weighing fluids with 

 this vcflei, one might err fix times more than this, yet it 

 would not aflFeft the point we have in view, which is not 

 to determine with the greateft accuracy the different 

 fpecific gravities of different lime-waters, but only to 

 fhew that they are different. 



