October 6, 1911] 



SCIENCE 



427 



that is engraven over the grave of that great 

 anatomist, John Goodsir (as it was over 

 that of the greatest of the Bernouillis), so 

 graven because it interprets the form of 

 every molluscan shell, of tusk and horn 

 and claw and many another organic form 

 besides. I like to dwell upon those lines 

 of mechanical stress and strain in a bone 

 that give it its strength where strength is 

 required, that Hermann Meyer and J. 

 Wolff described, and on which Roux has 

 bestowed some of his most thoughtful 

 work; or on the "stream-lines" in the 

 bodily form of fish or bird, from which the 

 naval architect and the aviator have 

 learned so much. I admire that old paper 

 of Peter Harting's in which he paved the 

 way for investigation of the origin of spic- 

 ules, and of all the questions of crystalliza- 

 tion or pseudo-crystallization in presence 

 of colloids, on which subject Lehmann has 

 written his recent and beautiful book. I 

 sympathize with the efforts of Henking, 

 Ehumbler, Hartog, Gallardo, Leduc and 

 others to explain on physical lines the 

 phenomena of nuclear division. And, as I 

 have said to-day, I believe that the forces 

 of surface-tension, elasticity and pressure 

 are adequate to account for a great multi- 

 tude of the simpler phenomena, and the 

 permutations and combinations thereof, 

 that are illustrated in organic form. 



I should gladly and easily have spent all 

 my time this morning in dealing with these 

 questions alone. But I was loath to do so, 

 lest I should seem to overrate their impor- 

 tance, and to appear to you as an advocate 

 of a purely mechanical biology. 



I believe all these phenomena to have 

 been unduly neglected, and to call for more 

 attention than they have received. But I 

 know well that though we push such ex- 

 planations to the uttermost, and learn 

 much in the so doing, they will not touch 

 the heart of the great problems that lie 



deeper than the physical plane. Over the 

 ultimate problems and causes of vitality, 

 over what is implied in the organization of 

 the living organism, we shall be left won- 

 dering still. 



To a man of letters and the world like 

 Addison, it came as a sort of revelation 

 that light and color were not objective 

 things but subjective, and that back of 

 them lay only motion or vibration, some 

 simple activity. And when he wrote his 

 essay on these startling discoveries, he 

 found for it, from Ovid, a motto well worth 

 bearing in mind, causa latet, vis est notis- 

 sima. We may with advantage recollect it, 

 when we seek and find the force that pro- 

 duces a direct effect, but stand in utter 

 perplexity before the manifold and trans- 

 cendent meanings of that great word 

 ' ' cause. ' ' 



The similarity between organic forms 

 and those that physical agencies are com- 

 petent to produce still leads some men, such 

 as Stephane Leduc, to doubt or to deny 

 that there is any gulf between, and to hold 

 that spontaneous generation or the artifi- 

 cial creation of the living is but a footstep 

 away. Others, like Delage and many more, 

 see in the contents of the cell only a com- 

 plicated chemistry, and in variation only a 

 change in the nature and arrangement of 

 the chemical constituents ; they either cling 

 to a belief in "heredity," or (like Delage 

 himself) replace it more or less completely 

 by the effects of functional use and by 

 chemical stimulation from without and 

 from within. Yet others, like Felix Auer- 

 bach, still holding to a physical or quasi- 

 physical theory of life, believe that in the 

 living body the dissipation of energy is 

 controlled by a guiding principle, as 

 though by Clerk Maxwell's demons; that 

 for the living the law of entropy is thereby 

 reversed; and that life itself is that which 

 has been evolved to counteract and battle 



