BULK OF EQUAL WEIGHTS OF BODIES. 



89 



water, the heaviest body, platinum and this 

 gas, and observe how they differ in this re- 

 spect ; for if I take a piece of platinum of that 

 size (fig. 29), it is equal to the weight of portions 

 of water, air, and hydrogen of the bulks I have 

 represented in these spheres ; and this illustra- 

 tion gives you a very good idea of the extra- 

 ordinary difference with regard to the gravity 

 of the articles having this enormous difference 

 in bulk. [The following tabular statement hav- 

 ing reference to this illustration appeared on 

 the diagram board.] 



Whenever oxygen and hydrogen unite to- 

 gether they produce water, and you have seen 

 the extraordinary difference between the bulk 

 and appearance of the water so produced and 



