30 EVOLUTION AND MAN S PLACE IN NATURE 



the protoplasm of any of their fellows, or of any 

 plant ; but here the assimilative powers of the animal 

 world cease. A solution of smelling salts in water, 

 with an infinitesimal proportion of some other saline 

 matters, contains all the elementary bodies which 

 enter into the composition of protoplasm, but ... a 

 hogshead of that fluid would not keep a hungry man 

 from starving, nor would it save any animal whatever 

 from a like fate. l 



Let us, however, for a moment suppose some large 

 advance in scientific knowledge, carrying an explana 

 tion even of the origin of life. Suppose the secret at 

 length discovered of the mode in which the forces of 

 gravitation, with aid of moisture, light, and heat, are 

 brought to bear on material molecules, so as to 

 produce the lowest phase of living material. Suppose 

 a mechanico-chemical theory of the origin of life 

 were thus obtained, what then ? Even then, we 

 have under observation only the very lowest and least 

 phase of vital movement in the world, a mere speck or 

 point of living material, a nucleus of vitality, or, at 

 best, a mass of such material ; and before us rises the 

 stupendous conception of elaborating out of this the 

 whole varieties of organism spread over the earth. 



Proceeding on the results of investigations dating 

 no further back than A.D. 1830, protoplasm, the 

 simplest living material, supplies the physical basis 

 of life. This soft jelly-looking substance is not 

 structurally of a simple character, as was supposed 

 when its existence was first recognised. Professor Sir 

 William Turner, in his vivid and concise account of 

 the cell theory, says it consists of two parts, viz., a 



1 Huxley s Lay Sermons, p. 147. 



