228 NATURE AND LIFE. 



Therapeutics has been aided, and may be more and 

 more benefited, by the labors of physicists. The employ- 

 ment of electricity, heat, cold, magnetism, and light, in the 

 treatment of diseases, is yet in its earliest stages, though 

 momentous results have even now been gained. We shall 

 need to study with careful exactness the action . of these 

 various forces on the human system. Are not these very 

 forces closely linked to the cosmic medium in which we 

 live, a medium swayed by the general conditions of celes- 

 tial mechanism ? This is saying that the advance of medi- 

 cal art is not independent of progress in investigations 

 upon the relations of the organism with agents which seem 

 to touch it but slightly, and from afar. 



Thus, history displays to our view all the sciences in 

 constant mutual reaction, and completing their improve- 

 ment by the reciprocation of profound influences. It is 

 thus that they sustain each other inseparably in commun- 

 ion, and that the blended power of the whole gives at 

 length, to the healing art as well as to industries of every 

 other kind, increasing vigor and certainty. Such is the 

 virtue of meditations and systematic experiments under- 

 taken without any concern for the useful ; but precisely 

 because this manifold and painstaking evolution is per- 

 formed unconsciously, to those who are its workmen, under 

 the influence of a small number of general ideas of which 

 philosophy is the perpetual source, it results that the 

 sciences, enriched by philosophy, minister in their turn 

 to its advance and perfection. 1 



1 This essay may properly be completed by noting the labors which 

 have lately led Eabuteau to suggest and recommend the protochloride 

 of iron as that salt of iron which is most readily absorbed, and best 

 adapted to the treatment of the many diseases in which preparations of 

 iron are required. 



