64 



THE NERVOUS SYSTEM 



commerce " of the spinal cord. Later, in 1837, he 

 demonstrated the course of nerve-impulses along the 

 cord from one level to another, the results of direct 

 stimulation of the cord, and other facts of spinal 

 localisation. He noted the different effects of 

 opium and of strychnine on reflex action ; and he 

 extended the doctrines of reflex action beyond 

 physiology to the convulsive movements of the body 

 in certain diseases. 



3. Flour ens (1794- 1867). 



Beside his work on the nervous system, Flourens 

 studied the periosteal growth of bone, and the 

 action of chloroform ; # but he is best known by his 

 experiments on the respiratory centre and the 

 cerebellum. The men who interpreted the nervous 

 system followed the anatomical course of that 

 system : first the nerve-roots, then the cord, then 

 the medulla oblongata and the cerebellum, and last 

 the cerebral hemispheres ; a steady upward advance, 

 from the observation of decapitated insects to 

 the localisation of centres in the human brain. 

 Flourens, by his work on the medulla oblongata, 

 localised the respiratory centre, the nerve-cells for 

 the reflex movements of respiration : — 



* When Flourens died, Claude Bernard was appointed to 

 his place in the French Academy ; and, in the Discours de 

 Reception (May 27, 1869), said, "It is twenty-two years since 

 the discovery of anaesthesia by ether came to us from the New 

 World, and spread rapidly over Europe. M. Flourens was the 

 first man who showed that chloroform is more active than 

 ether." 



