PREFACE TO THE FIRST EDITION 



IN writing this account of the Rothamsted Experiments the 

 sixty years' work of two men, Lawes and Gilbert, whose names 

 have become familiar in every part of the world where agri- 

 culture is something more than a matter of tradition and 

 custom I am of necessity acting as an external demonstrator, 

 describing from the outside, as it were, what seem to be the 

 chief lessons conveyed by the experiments which I have now 

 the honour to conduct. Lawes and Gilbert are dead, and with 

 them passed away many observations of value and many notable 

 generalisations which they had found no opportunity of giving to 

 the world, nor had I the personal contact with either which 

 would enable me to report even such portions of their experi- 

 ences as might have been conveyed by conversation. But 

 though these losses cannot be repaired, and though nothing 

 can replace the instinctive knowledge that comes of having 

 seen a thing grow year after year, yet the position of an out- 

 sider has some advantages, especially when drawing up an 

 account which, like the present, is addressed to the general 

 student of the subject. 



In the first place, the outsider approaches the consideration 

 of each experiment without any of the prepossessions arising 

 from too exclusive a recollection of the purpose with which the 

 experiment was originally framed. Headers of the Rotham- 

 sted Memoirs will know how certain ideas, e.g., the source and 

 function of the nitrogen in vegetation, occupied the minds of 

 Lawes and Gilbert from the very beginning of their experiments 

 until the end. In consequence, the papers on specific investi- 



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