3:^0 M . Becqucrel on the Relations of Natural Philosophy 



so soon as these same particles begin to be subjected to the in- 

 fluence of those forces which influence inorganic nature. 



We have here been speaking of those contractions which are 

 produced by physical stimuli of some sort ; and now it may be 

 inquired, Are the effects the same when they are called into acti- 

 vity by the power of the will ? The answer to this question may 

 be beyond the reach of man, but there is nothing which prevents 

 us from endeavouring to discover some of the physical causes 

 which contribute to the production of this great act of organic 

 nature. 



When, for example, we see, in the experiments of Galvani, of 

 Aldini, and of Dr Andrew Ure, upon those recently executed, 

 the different movements of the body, and especially of the face, 

 reproduced with a frightful reality, may we not be permitted to 

 suppose that nature, on other and common occasions elaborating 

 the electric fluid in the brain by means which escape our obser- 

 vation, thereby disposes it to put certain parts in motion without 

 interfering with the harmony of others, in a manner more regu- 

 lar, and, consequently, less inordinate, than the philosopher does 

 with his apparatus ? 



Now, there are so many means of exciting the electrical power 

 in the body, since the slightest derangement in their constituent 

 parts is sufficient to disturb the state of equilibrium, that it may 

 very readily happen that the will, by some kind of instinctive 

 feeling, as in the torpedo, agitates some points of the brain, for 

 the purpose of putting the electricity into motion, and which is 

 accordingly transmitted immediately by the nerves to the muscles 

 in which they are ramified. 



To whatever side we direct our attention, we discover that the 

 phenomena under our view depend upon some other phenomena, 

 so very close is the alUance which subsists between the various 

 natural agents. Phosphorescence is a' good proof of this. It is 

 this property so worthy the especial attention of the philosopher, 

 the chemist, and the physiologist, which enables perhaps the ma- 

 jority of bodies to become luminous in the dark, and sometimes 

 in open day, by the agency of heat, light, friction, percussion, com- 

 pression, electrical discharges, chemical action, sometimes violent, 

 sometimes gentle, and the vital powers when subjected to the 



