74: NERVOUS SYSTEM. 



ber of the journal, lie gives a full analysis of it. 1 In this 

 number, also, he speaks of having repeated the experiments. 

 In the same journal, follows a translation of the experiments 

 of Mr. Shaw. 2 In none of these publications is there any 

 allusion to the properties of the anterior and posterior roots 

 of the spinal nerves, nor is there any evidence that either 

 Bell, Shaw, or Magendie knew any thing about the distinct 

 seat of motion and sensation in the spinal cord and the spi- 

 nal nerves. 3 



In August, 1822, Magendie published his first experi- 

 ments on the functions of the roots of the nerves. 4 Unlike 

 any of the observations made by Charles Bell on the spi- 

 nal nerves, these were made upon living animals. The spi- 

 nal canal was opened, and the cord, with the roots of the 

 nerves, exposed. The posterior roots of the lumbar and sacral 

 nerves were then divided upon one side and the wound united 

 with sutures. The result of this observation was as follows : 



" I thought at first that the limb corresponding to the 

 divided nerves was entirely paralyzed ; it was insensible to 

 pricking and to the most severe pinching, it also appeared 

 to me to be motionless ; but soon, to my great surprise, I 

 saw it move in a very marked manner, although the sensi- 

 bility was still entirely extinct. A second, a third experi- 

 ment, gave me exactly the same result ; I commenced to 

 regard it as probable that the posterior roots of the spinal 

 nerves might have functions different from the anterior roots, 

 and that they were more particularly devoted to sensibility." 6 



1 BELL, Suite de recherches anatomiques et pliysiologiques sur le systeme nervewx. 

 Journal de physiologic, Paris, 1822, tome ii., p. 66, et seq. 



2 SHAW, Experiences sur le systeme nerveux. Extrait et traduit de V Anglais 

 par M. Cairns. Journal de physiologic, Paris, 1822, tome ii., p. 77, et seq. 



3 In the same volume of the journal (p. 363), Magendie gives an account of 

 Bell's observations on the respiratory nerves of the chest, which were presented 

 to the Royal Society, May 2, 1822. 



4 MAGENDIE, Experiences sur le* fonctions des racines des nerfs rachidiens. 

 Journal de physiologic, Paris, 1822, tome ii., p. 276, et seq. 



5 Ibid., p. 277. 



