MOTOR AXD SENIORY NERVES. 71 



Bell regarding the properties of the two roots of the spinal 

 nerves ; but now that an authorized reprint can be so readily 

 consulted, it is only necessary to refer to this to show that 

 Bell did not at that time regard the anterior roots as motor 

 and the posterior roots as sensory, but that he thought that 

 the anterior roots were for both motion and sensation and 

 the posterior roots presided over "the secret operations of 

 the bodily frame, or the connections which unite the parts 

 of the body into a system." l 



All the credit which we have to give to Sir Charles Bell 

 for advances in the anatomy and physiology of the spinal 

 nerves must cease with the review of the pamphlet of 1811. 

 In a memoir on the nerves of the head, read before the 

 Royal Society, July 12, 1821, more than a year before the 

 publication of the experiments of Magendie, there is no men- 

 tion of distinct motor and sensitive roots of the spinal nerves, 

 nor of distinct properties in different portions of the spinal 

 cord. This paper was republished by Bell, after the pub- 

 lication of Magendie' s observations, in a work on the nervous 

 system ; and it is this republication which is most accessible 

 and most frequently referred to by physiological writers. 

 The republication avowedly contains " some additional ex- 

 planations ; " but a careful comparison of it with the original 

 shows that every portion of it that was susceptible of such 

 verbal alteration had been modified to make it correspond 

 with the discovery by Magendie. But, at the same time, the 

 impression received by the reader is, that it is essentially the 

 same as the memoir published in 1821. 3 'In the controver- 

 sial condition of the question at the time of this republication, 

 the alterations and " additional explanations " ought certainly 



1 In a paper read before the Medico-Chirurgical Society, in April, 1822, Mr. 

 J. Shaw gives the date of the first paper by Charles Bell, as 1809. This error is 

 quoted into many reviews and other publications, but it has been corrected by 

 Bell himself, and by Mr. A. Shaw. (ALEXANDER SHAW, Narrative of the Discov- 

 eries of Sir Charles Sell in the Nervous System, London, 1830, p. 14.) 



8 CHARLES BELL, The Nervous System of the Human Body, London, 1844, p, 

 33 et seq. 



