35 G DISEASES OF THE SPINAL COED AND ITS MEMBEAXES. 



CHAPTER YII. 



DISEASES OF THE SPINAL CORD AND ITS MEMBRANES. 



General Remarks. — The diseases of this part of the nervous 

 system are as difficult to understand in many of their manifes- 

 tations, and in their investigation are surrounded Avith ob- 

 stacles as great, as those pertaining to the brain proper. These 

 difficulties are not of one class or one sided ; they are difficulties 

 as respect time and opportunities for experiments and research, 

 as well as intelligence and fitness for the investigation. If 

 many of the doctrines hitherto taught relative to the diseases 

 affecting the cerebral nervous structures are, at the present 

 time, justly regarded as nearly in a transition stage, certainly 

 nothing more definite or flattering can be affirmed concerning 

 those of the spinal cord. 



The amount, as well as exactness, of the loiowledge possessed 

 respecting the structure and functions of this part of the 

 nervous system has always had a powerful influence in deter- 

 mining the views held, not merely regarding the diseases to 

 which it is liable, but also the value we are to place upon many 

 of the most prominent symptoms, and the inferences which 

 may be deduced from these. 



Our present knowledge leads us to regard the cord not as a 

 mere aggregation of nerve-trunks, nor yet as a simple extension 

 of the cerebral matter contained within the cranial case, but as 

 an important and independent nervous centre, as well as being 

 intimately connected both in structure and function with the 

 brain proper, and the nerve-cords which issue from or run 

 into itself 



From the similarity which exists between the ultimate struc- 

 ture of the cord and cerebral nervous centre, we would naturally 

 anticipate a close resemblance in the character of their diseases, 

 and the alterations which these structures show on after-death 

 examination. The healthy functional activities, however, of 

 these centres being dift'erent, the disturbed or morbid actions 

 which originate from these, to Avhich we give the name of 

 disease symptoms, are modified accordingly. From the extent 

 of discrepance which exists amongst experimenters regarding 

 the functions of the different parts of the cord, it follows as 



