190 THE FORCE INCLUDED IN PLANTS. [MEMOIR XL 



sume if it comes to a precipitous descent a form which, 

 though it may be outwardly unchanging, is interiorly 

 never for two successive moments the same, for it is per- 

 petually fed from above and is wasting away below so 

 the flame of a lamp is only a form, the aspect of which is 

 determined by its environment. The changes it is under- 

 going issue in the liberation, the escape, of force, chiefly 

 under the aspect of light and heat. Its life is very tran- 

 sitory. It dies out as soon as the oil that fed it is ex- 

 hausted. We blow upon it, and it passes into nonentity. 

 And so, too, with an animal, the appearance of identity 

 it presents is altogether deceptive. At no two succes- 

 sive moments are its parts the same. In a very short 

 time all the old have been removed, and new ones have 

 taken their places. The force that it derived from its 

 food has been manifested in various ways, such as mus- 

 cular motion or heat. But the material particles have 

 not been destroyed ; they have merely gone back into 

 the atmosphere, and will be used by nature for the fab- 

 rication of other plant and animal forms over and over 

 again. And so, too, the energy they have displayed it 

 has not ceased to exist ; the heat, for instance, that once 

 vivified them has merely mingled with that of the outer 

 world, and is ready to discharge its special functions 

 again and again. In the world there is thus an unceas- 

 ing transmigration of matter, an unceasing transmigra- 

 tion of force. 



