PREFATORY NOTE 



I acknowledge with gratitude the helpful kindnesses 

 of many busy men. In the preparation of the narra- 

 tive supplementing these letters of my father and his 

 friends I have availed myself of material gathered 

 from the writings of men of science whose names 

 either figure in these pages or are well known to 

 present-day workers in our Agricultural Colleges and 

 Stations. In a few instances I have borrowed not 

 only the spirit, but the letter of their text — lest through 

 clumsy transposition an expression should lose its 

 clearness. Whenever possible, I have asked permis- 

 sion for my action. The cordial assent given in each 

 case emboldens me to request the few with whom I 

 have been unable to communicate to accept my thanks 

 and this general acknowledgment. 



E. A. 0. 



