8 - The Principles of Part 1. 



any other plan, can never certainly lead to 

 truth. I mall not, therefore, proceed a 

 fingle ftep without fact and experiments; 

 and when I am not fupplied with them 

 from others, mail endeavour to make them 

 rnyfelf. It is laborious, but it is necelTary. 



SECT. II. 



Of different foils. 



AS the earth is the matrix to which 

 all feeds are committed, and from 

 which all vegetables take the whole, or at 

 leaft the greateft part of their nou'rim- 

 ment, it is proper to begin with an exami- 

 nation of it. As it nourifhes plants with- 

 out the affiftance of art, it mufl contain 

 the food of plants. If we can difcover 

 what is the natural food of vegetables, we 

 fhall the eafier difcover wherein confifts 

 their artificial food, or that given by art, 

 and how it operates. 



EARTHS 



