Fluid Pressure 



89 



of brass and iron respectively. Weigh each cylinder 

 carefully, having previously attached a length of 

 about 12" of stout thread to each. Over the left- 

 hand pan of the balance place a bridge a flat board 

 supported on two blocks of wood of equal height will 

 do of such a height that the pan may move freely 

 beneath it (this bridge is shown in Fig. 27). On 

 the bridge place a vessel of water large enough to 

 hold the cylinders without danger of their coming in 

 contact with the inner wall 

 of the vessel. Suspend each 

 cylinder in turn from the 

 stirrup at the left-hand end 

 of the beam by means of 

 the thread, and weigh each 

 body when entirely sub- 

 merged in the water and 

 out of contact with the 

 vessel. % The upthrust on 

 the cylinders will cause 

 their weights, when in the 

 liquid, to appear to be less 

 than when they were 

 weighed in the air. Note 

 and compare the apparent 

 losses of weight. 



Repeat these operations with another cylinder made 

 of one of the materials previously used, but of different 

 volume. 



The apparent loss of weight in each case is caused 

 by the upthrust of the liquid on the solid. Determine 

 the volume of each body used and hence find the weight 

 of the water displaced by it. Compare the weight of 

 the displaced water in each case with the corresponding 



Fig. 27. 



