CHAPTEE VI. 



USE AND DISUSE, REVERSION, AND HYBRIDISM. 



" For unto every one that hath shall be given, and he shall have 

 abundance ; but from him that hath not, shall be taken away even that 

 which he hath." Matth. xxv. 29. 



THE amount of Energy in the universe is a fixed 

 quality, which we have reason to believe can 

 neither be added to nor diminished by any 

 power short of a miracle analogous- to that of 

 Direct Creation. Hence the failure of all at- 

 tempts to produce perpetual motion, or in other 

 words, to provide a store of energy which will 

 not sooner or later expend itself. The vitality 

 of animals and plants is only maintained by the 

 nourishment which they derive from air and 

 water, as well as from the earth and its products ; 

 and it also appears that every living being has a 

 certain amount of latent vital force, varying in 

 different individuals, and capable of being much 

 modified by surrounding circumstances. But 

 although it may be exhausted faster or slower, its 

 ultimate exhaustion is inevitable, (for its recupe- 



