EXAMPLES. 71 



S = ? , (2) 



W + X W 



Hence, add the difference between the weights of the 

 heavy body and the two together in the water to the 

 weight of the solid in air, and divide the weight of the 

 solid in air by this sum. 



(3) To find the specific gravity of a liquid. 



Take a solid which is specifically heavier than either the 

 liquid or water, and let it be weighed in both ; then the loss 

 of weight in the two cases will be the respective weights of 

 equal volumes of the liquid and of water ; therefore, the 

 loss of weight in the liquid, divided by the loss of 

 weight in the water, will give the specific gravity of 

 the liquid. 



Let w = the weight of the solid in air, w' = its weight 

 in the liquid whose specific gravity is to be determined, and 

 Wj = its weight in water; then w w' and w w l are 

 the respective weights of equal volumes of the liquid and of 

 water; therefore 



B = =*-. (3) 



Iff W l 



Otherwise thus : Let w = the weight of an empty flask, 

 w' = its weight when filled with the liquid, and w l =. its 

 weight when filled with water ; then w' w and w^ w 

 are the respective weights of equal volumes of the liquid and 

 of water ; therefore 



8 = 2^?- (4) 



w l w 



EXAM PLKS. 



1. A cubical iceberg is 100 ft. above the level of the sea, 

 its sides being vertical. Given the specific gravity of sea- 

 water = 1.0263, and of ice = 0.9214 at the temperature of 

 32, to find its dimensions. 



