310 SIMPLE AND COMPOUND EVOLUTION. 



would occur if the constituents of the nitrogenous com- 

 pounds could be divorced without the addition of motion 

 from without, is too complex a question to be answered. 

 But respecting the constituents of that which forms some 

 four-fifths of the total weight of an ordinary animal its 

 water a tolerably definite answer can be given. Were the 

 oxygen and hydrogen of water to lose their affinities, and 

 were no molecular motion supplied to them beyond that con- 

 tained in water at blood-heat, they would assume a volume 

 twenty times that of the water.* Whether protein under 

 like conditions would expand in a greater or a less degree, 

 must remain an open question; but remembering the gase- 

 ous nature of three out of its four chief components, remem- 

 bering the above-named peculiarity of nitrogenous com- 

 pounds, remembering the high multiples and the colloidal 

 form, we may conclude that the expansion would be great. 

 We shall not be far w r rong, therefore, in saying that the ele- 

 ments of the human body if suddenly disengaged from one 

 another, would occupy a score times the space they do : the 

 movements of their atoms would compel this wide diffusion. 

 Thus the esential characteristic of living organic matter, 

 is that it unites this large quantity of contained motion with 

 a degree of cohesion that permits temporary fixity of ar- 

 rangement. 



104. Further proofs that the secondary re-distribu- 

 tions which make Evolution compound, depend for their 

 possibility on the reconciliation of these conflicting condi- 

 tions, are yielded by comparisons of organic aggregates 

 with one another. Besides seeing that organic aggregates 

 differ from other aggregates, alike in the quantity of motion 

 they contain and the amount of re-arrangement of parts that 

 accompanies their progressive integration ; we shall see that 

 among organic aggregates themselves, differences in the 



* I am indebted for this result to Dr. Frankland, who has been good enough 

 to have the calculation made for me. 



