PRESIDENTIAL ADDRESS, B.A. 1871. 197 



Think now of the admirable simplicity with 

 which Tait's beautiful " sea-bird analogy," as it has 

 been called, can explain all [?] these phenomena. 



The essence of science, as is well illustrated by 

 astronomy and cosmical physics, consists in 

 inferring antecedent conditions, and anticipating 

 future evolutions, from phenomena which have 

 actually come under observation. In biology the 

 difficulties of successfully acting up to this ideal 

 are prodigious. The earnest naturalists of the 

 present day are, however, not appalled or paralysed 

 by them, and are struggling boldly and laboriously 

 to pass out of the mere "Natural History stage" 

 of their study, and bring zoology within the range 

 of Natural Philosophy. A very ancient specula- 

 tion, still clung to by many naturalists (so much so 

 that I have a choice of modern terms to quote in 

 expressing it) supposes that, under meteorological 

 conditions very different from the present, dead 

 matter may have run together or crystallised or 

 fermented into " germs of life," or " organic cells," 

 or " protoplasm." But science brings a vast mass 

 of inductive evidence against this hypothesis of 



