THE EARTH. 157 



each other, and just as accident has formed them, 

 yet it heaved in great waves, like water. Upon 

 agitation, a heavy body will sink to the bottom, 

 and a light one emerge to the top. There is no 

 reason, then, to suppose the figure of the parts of 

 water round, since we see their fluidity very well 

 imitated by a composition, the parts of which are 

 of various forms and sizes. The shape of the 

 parts of water, therefore, we must be content to 

 continue ignorant of. All we know is, that 

 earth, air, and fire, conduce to separate the 

 parts from each other. 



Earthy substances divide the parts from each 

 other, and keep them asunder. This division 

 may be so great, that the water will entirely lose 

 its fluidity thereby. Mud, potter's clay, and dried 

 bricks, are but so many different combinations 

 of earth and water; each substance in which 

 the parts of water are most separated from each 

 other, appearing to be the most dry. In some 

 substances, indeed, where the parts of water are 

 greatly divided, as in porcelain, for instance, it is 

 no easy matter to recover and bring them toge- 

 ther again ; but they continue in a manner fixed 

 and united to the manufactured clay. This cir- 

 cumstance led Dr Cheney into a very peculiar 

 strain of thinking. He suspected that the quan- 

 tity of water, on the surface of the earth, was 

 daily decreasing. For, says he, some parts of it 

 are continually joined to vegetable, animal, and 

 mineral substances, which no art can again, re- 

 cover. United with these, the water loses its 

 fluidity ; for if, continues he, we separate a few 



