COSMIC PHILOSOPHY 



liquid matter flowing through solid matter — as 

 when currents of rain water, percolating through 

 loose soil, gradually break away obstructing par- 

 ticles and excavate small channels which ulti- 

 mately widen and deepen into river-beds — is 

 a case in which similar dynamic principles are 

 involved. In all these cases, " if we confine our 

 attention to that part of the motion which es- 

 caping transformation continues its course, then 

 it is a corollary from the persistence of force 

 that as much of this remaining motion as is 

 taken up in changing the positions of the units 

 must leave these by so much less able to ob- 

 struct subsequent motion in the same direc- 

 tion." ^ 



Now in the case of organic bodies, the enor- 

 mously complex molecular changes involved in 



first instance were refi'actory, to conform at last to the require- 

 ments of the vibrating strings." On Sound, p. 90. As Dr. 

 Maudsley would say, ** musical residua " remain in the molec- 

 ular structure of the wood. 



1 Spencer, First Principles, y>' 248. [Part II. chapter ix. 

 §81, near the close of the section.] Thus, though Mr. Mill 

 is justified in saying (^Inaugural Discourse, p. 62) that " phy- 

 siology is the first science in which we [distinctly] recognize 

 the influence of habit — the tendency of something to happen 

 again merely because it has happened before," — yet, as we 

 here see, the phenomena of habit are foreshadowed in the in- 

 organic world. An admirable instance of that continuity among 

 phenomena which is everywhere impHed by the theory of 

 evolution. 



210 



