THE CHEMICAL KEGULATION OF THE 

 PROCESSES OF THE BODY 1 



BY WILLIAM HENEY HOWELL, M. D. PH. D. 



AT the time of Sir Charles Bell, physiologists were begin- 

 ning to realize the great importance of the nervous system 

 as a mechanism for regulating and coordinating the varied 

 activities of the body. To use his own expression, "The 

 knowledge of what is termed the economy of an animal 

 body is to be acquired only by an intimate acquaintance 

 with the distribution and uses of the nerves." Since his 

 time experimental investigations in physiology and clinical 

 studies upon man have combined to accumulate a large 

 fund of information in regard to the regulations and cor- 

 relations effected through nervous reflexes. No one can 

 doubt that very much remains to be accomplished along 

 these same lines, but in recent years we have come to under- 

 stand that the complex of activities in the animal body is 

 united into a functional harmony, not only through a 

 reflex control exerted by the nervous system, but also by 

 means of a chemical regulation effected through the blood 

 or other liquids of the organism. The first serious realiza- 

 tion of the importance of this second method of regulation 

 came with the development of our knowledge of the inter- 

 nal secretions during the last decade of the nineteenth cen- 

 tury. The somewhat meager information possessed at that 

 time in regard to these secretions developed in the fertile 

 imagination of Brown-Sequard to a great generalization, 

 according to which every tissue of the body in the course 



'Address of the vice-president and chairman of Section K Physi- 

 ology and Experimental Medicine, American Association for the 

 Advancement of Science, Boston, December 28, 1909. From Science, 

 January 21, 1910. 



181 



