THE SYMPATHETIC SYSTEM 5 



the function of which is not yet determined. However, 

 these glands should be considered as playing a part in the 

 regeneration of the blood plasma as well as in the forma- 

 tion of white and red cells which float in this liquid." 

 The idea of internal secretions was clearly seen by Claude 

 Bernard, but in his mind they were alw r ays limited to the 

 composition of the blood and did not have the multiple 

 conceptions we have of these to-day in modern physi- 

 ology. For a long time the findings of Claude Bernard 

 failed to make any impression on his contemporaries and 

 they were not likened to those of Brown-Sequard on the 

 physiology of the suprarenal capsules and the death of 

 animals which had these capsules removed (1856) or to 

 the work of Vulpin on the coloring matter of the medullary 

 part of the suprarenal capsules (1856) and its passage into 

 the suprarenal veins, or to the work of Schiff on the rela- 

 tions of the spleen with the digestive functions of the 

 pancreas. When Schiff in 1884 published his experiments 

 on the effect of the removal of the thyroid in animals 

 researches resulting from the work of the two surgeons, 

 Reverdin and Kocher, on post-operative myxedema, he 

 did not think of the possibility of internal secretions as 

 established by Claude Bernard. 



It was Brown-Sequard in 1889 in his investigations of 

 the therapeutic action of testicular fluid who understood 

 the full value of the theory of internal secretions and who 

 founded endocrinology. His original researches can pos- 

 sibly be criticized ; they, however, contain the germ of all 

 the ideas which have been used as a starting point on all 

 the studies carried out during the last thirty years on 

 internal secretions. While taking up again the idea of 

 Claude Bernard on the action of glands without external 

 secretions on the composition of the blood he showed that 

 many organs secrete in the blood certain substances which 



