a Standard of ff eight and Meafure. 107 



be taken of the counterpoife weight, viz. 555,02 grains, or 552,34 grains refpeftively ; and 

 thefe are to be dedudted from the general amount of all the weights in the left-hand fcale 

 marked x ; but it certainly would have been more convenient to have had fmgle weights 

 ready adjufted for thefe counterpoifes, both in air and water. Thefe, though at firft omitted, 

 have flnce been fupplied. 



Grains. 



§ 1 8. The counterpoife to the fcale for the cube? _« , 7? 

 in diftilled water, with the heat of 6i» - ^— 44.75 



To diis add the weight of the common fcale as before = 4 1 3,40 



And we have the whole weight of the fcale for 7 _ o jg . 

 the cube in water - - - ^ — i » 5 



But the weight in air having already been found =968,40 



The difference of the weights _ - - =112,25 



Gives for the fpecific gravity of this brafs - = 8,61 



^ ig. The counterpoife to the fcale for the cy-7 —aai(\9L 



lindcr, in the fame water with the fame heat 3 ~" ' 

 To this add the weight of the common fcale as beforc=4 13,40 

 And the whole weight of the fcale for the cylinder 7 _o - - ^8 



in water becomes - - - 3 ~ 



Its weight in air has already been found - =965,74 



The difference of thefe weights - - =110,66 



Gives for the fpecific gravity of this brafs - =8,78 



The mean fpecific gravity of this brafs, and brafs-? _ g 

 wire, may therefore be put about - 3 — »7 



N.B. The tables of fpecific gravity, give that of wrought brafs from 8,00 to 8,20. 

 It was neceffary to afcertain the fpecific gravity of the brafs wire, to make the corredlion 

 mentioned in the note to § 10 ; for as it was highly poffible that in experiments with this 

 hydroftatic balance, the fcales for the cube and cylinder would occafionally be immerfed to 

 different depths in the water, and their weights would be altered as more or lefs of the 

 wires, by which they were fufpended, remained out of the water. 



Grains, 

 laccordingly found that 80 inches in length of 

 this wire, ufed in the fcdes for the cube and ] 

 cylinder, weighed in air 



And confequently i inch would be =0,077 grains, and fourivires of 1 inch =,308 grain, 

 which divided by the fpecific gravity, viz. |^, would give 0,0354 grain for the corre&ion of 

 every inch that the fcale was funk lower in the water ; and fo in proportion. 



(Tt be conttHutd^) 



P» LtMf 



Lxrarns 

 id J =6.16 



