144 HISTORY OF 



being mixed with earth and ashes, and formed into 

 a vessel, when baked before the fire becomes a 

 coppel, remarkable for this, that it will bear the 

 utmost force of the hottest furnace that art can 

 contrive. So the Chinese earth of which por- 

 celain is made, is nothing more than an artificial 

 composition of earth and water united by heat ; 

 and which a greater degree of heat could easily 

 separate. Thus we see a body, extremely fluid 

 of itself, in some measure assuming a new nature, 

 by being united with others; we see a body, 

 whose fluid and dissolving qualities are so ob- 

 vious, giving consistence and hardness to all the 

 substances of the earth. 



From considerations of this kind, Thales, and 

 many of the ancient philosophers, held that all 

 things were made of water. In order to confirm 

 this opinion, Helmont made an experiment, by 

 divesting a quantity of earth of all its oils and 

 salts, and then putting this earth, so prepared, 

 into an earthen pot, which nothing but rain-water 

 could enter, and planting a willow therein : this 

 vegetable, so planted, grew up to a considerable 

 height and bulk, merely from the accidental asper- 

 sion of rain-water ; while the earth in which it 

 was planted received no sensible diminution. 

 From this experiment he concluded, that water 

 was the only nourishment of the vegetable tribe ; 

 and that vegetables being the nourishment of 

 animals, all organized substances, therefore, owed 

 their support and being only to water. But this 

 has been said by Woodward to be all a mistake j 

 for he shows, that water being impregnated with 



