I am far from allowing the truth of this obfervatlon taken in 

 its totality ; to refute it we need only compare the writings of 

 Cato, Columella or Pliny, with many modern Tracfls, or ftill 

 better, with the modern pradice of our heft farmers ; it mull 

 be granted, however, that vague and fortuitous experience has 

 contributed much more to the prefent flourlfhing flate of this 

 art than any general principles deduced from our late acquired 

 knowledge, either of the procefs of vegetation, or of the nature 

 of foils ; but the jdiill thus fortuitoufly acquired is necelTarily 

 partial, and generally local ; the very terms employed by the 

 perfons who moft eminently poflefs it are generally of a vague 

 and uncertain fignification. Thus Mr. Young, to whofe labours 

 the world is more indebted for the diffufion of agricultural 

 knowledge than to any writer who has as yet appeared, remarks 

 that in fome parts of England, where hufbandry is fuccefsfully 

 pradifed, any loofe clay is called marie*; in others marie is 

 called chalk f, in others clay is called loam J. Philofophic 

 refearches have been made, not yet fufficiently noticed ; much 

 information may be derived from Monfieur Du Hamel, and 

 much more from the well-diredled experiments of Mr. Tillet §. 

 Immenfe flrides have been made in this career by the illuftrious 

 Bergman ; Dr. Prieftley's experiments have thrown a new light 

 on this as well as on every other objedl of natural philofophy. 

 Mr. Lavoifier's new theory explains many circumftances before 



inexplicable ; 



• Firft Eaftern Tour 178. +2 Bath. Mem. 192. 220. 



% 2 Bath. Mem. 137. J Mem. Par. 1772. 



