[ 171 3 



Thofe tilings then which are felt, perceived, and 

 produce the fame fenfations and affedlions in all 

 men, and every where, may be depended upon as 

 truths infallibly certain, beyond a poflibility of de- 

 ception. Not fo experiments made by the moft: 

 careful and the moft candid, till they have been 

 repeated again and again; and the firft trials con- 

 firmed and duly authenticated by fubfequent ones. 

 Much more is to be feared from the cunning, the 

 artifice, the prepofTeflion, the prejudice, the vanity, 

 and the intereft, of defigning men, who too fre- 

 quently have been found to warp and bend their 

 accounts, to promote their interefted views. 



It is in the obfervation of every man, from the 

 illiterate occupier of a cottage to the firft gardener 

 of a prince, that all kinds of animal fubftances, 

 when thoroughly digefted and corrupted, are the 

 ftrongeft and moft powerful promoters of vegeta- 

 tion. The hair, the Ikin, the horns and hoofs, the 

 urine and excrements, the flefti, blood, finews, and 

 even the bones, are all richly replete with matter 

 which fupports and invigorates vegetation univer- 

 fally. It is therefore undeniably certain, that ani- 

 mal fubftances contain thofe principles which are 

 the real and genuine food of plants. It is abfurd 

 therefore to fuppofe their food is earth, or water, 

 or air, fire, or heat, or any one fimple element or 



thing 



