THE PHYSICAL J*> A S 1 S 



OF LIFE 



^* 



I HAVE been much honored by the invitation to speak 

 on this occasion, but for me it has meant more ; for the 

 man in whose memory the Sedgwick Memorial Lec- 

 tureship has been established was my lifelong and cher- 

 ished friend. My theme today is drawn from an infinitesi- 

 mal but all-including world, bounded by the horizon of the 

 compound microscope, a world that may seem far distant 

 from Sedgwick's own broad domain of sanitary science 

 and the jDublic health. I am sure, however, that such would 

 not have been his owai view ; for Sedgwick was one of the 

 pioneer teachers of general biology in this country, and 

 it was his lifelong habit to think of the phenomena of life 

 in terms of the activities of protoplasm. 



I have a lively recollection of how he and I, in the days 

 of our youth, when fellow students at Yale, fell under the 

 spell of Huxley's Edinburgh address on the Physical 

 Basis of Life,^ at that time still a subject of widespread 

 popular discussion. In this celebrated discourse the emi- 

 nent English biologist set forth certain general conclu- 

 sions concerning protoplasm which had gradually taken 

 shape through the work of such investigators as De 

 Bary, Max Schultze, Kiihne, Briicke and Lionel Beale. 

 Huxley's presentation of the subject was a masterpiece 

 both of English style and of philosophical breadth of out- 

 look. In part for this reason, still more because of its sup- 



*A few references to the literature, indicated In' numerals in the 

 text, Avill he found at the end. 



