FERTILISERS AND MANURES 



CHAPTER I 



INTRODUCTORY 



Early Notices of Manures and Manuring — History of the Theory 

 of Nutrition of Plants — Priestley, de Saussure, BoussingaulL 

 Liebig, Lawes and Gilbert, Hellriegel and Wilfarth — The 

 Introduction of Commercial Fertilisers — General Outline of 

 the Process of Nutrition of Plants — The Constituents of the 

 Soil — Mode of Entry of Food into the Plant — Nature and 

 Function of a Fertiliser. 



The word " manure," when first met with in English, 

 possessed a much wider significance than it does 

 to-day. Of the same origin as manoeuvre, it meant, 

 primarily, to work by hand, and it is used in that sense 

 by Defoe in Robinson Crusoe — " The land which I had 

 manured or dug"; but it also took on the extended 

 meaning of any process or material by which the land 

 could be ameliorated. In the seventeenth and early 

 eighteenth centuries this latter sense alone began to 

 prevail ; agricultural writers enumerated chalk, lime, 

 marl, burnt clay, etc., as manures, and began to speak 

 of the operations of cultivation as tillages or husbandry ; 

 and more recently the tendency has been to restrict 

 the employment of the term even further, confining 

 it to the natural substances possessing a direct fertilising 



A 



