4 INTRODUCTORY [chap. 



had even begun to reason a little on the mode of action 

 of manures. For example, Bernard Palissy the potter, 

 in his Recepte Veritable, published in 1563, not only 

 recommends the use of marl and lime, but can assign a 

 reason for the value of ashes, and shows that the rich- 

 ness of farmyard manure resides in the portion soluble 

 in water : — " Et ainsi la paille estant bruslee dedans 

 le champ, elle scruira d'autant de fumier, parce que 

 elle laissera la mcsmc substance qu'cll auoit attiree 

 de la terre ... ; " and again, " au lieu ou ledit pilot de 

 fumier aura rcposd quelquc temps, ils n'y laisseront 

 rien dudit fumier, avis le jetteront dc?i\ et dela, mais 

 au lieu ou il aura repose quelque temps, tu verras 

 qu'apres que la blc qui aura est6 sem6 sera grand, il 

 sera in cest cndroit plus espes, plus haut, plus verd et 

 plus droit. Par W tu pcux aisement cognoistre que cc 

 n'est pas le fumier qui a caus6 cela, car le labourer le 

 jette autre part ; mais c'est que quand ledit fumier estoit 

 au champ par pilots, les pluyes qui sont suruenues, ont 

 pass^ a travers des dits pilots, et sont descendu a travcrs 

 du fumier jusqu'^ la terre, et en passant, ont dissout et 

 emportc certains parties du sol qui estoit audit fumier." 

 If, then, by the sixteenth century we find written 

 evidence of the knowledge of the fertilising properties 

 not only of dung but of other waste substances, we 

 may safely push back the original discovery of the 

 properties of these bodies to a much more remote epoch, 

 if such a term as discovery can properly be applied. 

 Just as happens to-day, this or that man tried an 

 experiment or noticed the result of an accident which 

 caused him to report well of the action of some sub- 

 stance on his crops ; his opinion would often be 

 mistaken and often, again, it would be forgotten ; but 

 occasionally it would be repeated and find confirmation, 

 until it acquired the wide circulation and staying power 



