54 



THE NERVOUS SYSTEM 



diseases of the cerebellum appeared to tell on the 

 movements of the heart. . . . Haller believed it 

 to be the seat of sensations, as well as the source 

 of voluntary power ; and there were many sup- 

 porters of the theory that the cerebellum was the 

 seat of the sensory centres. Renzi considered this 

 organ the nervous centre by which we perceive the 

 reality of the external world, and direct and fix our 

 senses on the things round us. Gall, and later 

 Broussais, and others, held that this organ presided 

 over the instinct of reproduction, or the propensity 

 to love ; while Carus regarded it as the seat of the 

 will also. Rolando looked on it as the source of 

 origin of all movements. Jessen adduced argu- 

 ments in favour of its being the central organ of 

 feeling, or of the soul, and the principal seat of the 

 sensations." 



It is plain, from this list, that physiology had 

 become obscured by fanciful notions of no practical 

 value. If a better understanding of the nervous 

 system could have been got without experiments 

 on animals, why had men to wait so long for it ? 

 The Italian anatomists had long ago given them 

 all the anatomy that was needed to make a begin- 

 ning ; the hospitals, and practice, had given them 

 many hundred years of clinical facts ; nervous 

 diseases and head injuries were common enough 

 in the Middle Ages ; and by the time of Ambroise 

 Pare, if not before, post-mortem examinations were 

 allowed. The one thing wanted was the experi- 

 mental method ; and, for want of it, the science of 

 the nervous system stood still. Experiments had 

 been made ; but the steady, general, unbiassed use 



