DEDICATED TO 



SIR CHARLES LAWES-WITTEWRONGE, Baronet 



OF ROTHAMSTED 



WHO HAS SHOWN IN OTHER FIELDS 



THE DISTINCTION AND IMAGINATION 



WHICH MARKED HIS FATHER'S WORK 



FOR AGRICULTURE 



First Edition ...... June 1909 



Reprintid ...... June 1910 



Reprinted ...... May 1912 



Reprinted ...... Nov. 1913 



