246 PHYSIC 



other varieties, except those of purely external origin, 

 must, therefore, be a disease, primarily, of the nervous 

 system, first invading the cerebro-spinal cavity and its 

 contents, and secondarily, the systemic peripheral and 

 cutaneous nerve coverings, endings, and inter-spaces. 

 The sequence of the pathological events characterising the 

 onset and progress of the disease, the nature of the struc- 

 tures selected by it, as the theatre for the display of its 

 morbid processes, the correspondence of the extravasated 

 fluid, in consistence and appearance, with cerebro-spinal 

 fluid, or lymph, plus, it may be, an admixture of neuro- 

 keratinous material, due to rupture and disintegration of 

 the containing textures, surrounding the terminal arbori- 

 sations of the cutaneous nerve fibrils, all lend themselves 

 to prove that we have to deal with a disease of the nervous 

 system. 



In this connection, the occurrence of what are denomi- 

 nated keratosis and hyperkeratosis, may be said to be due 

 to the pathologically free discharge into the peri-nervine 

 textures of cerebro-spinal fluid, loaded with neuro-kera- 

 tine, and, it may be, the medullary and axis cylinder 

 substances, filtered through the disorganised remains of 

 the neuro-keratine sheaths surrounding the final divisions 

 of the terminal fibrils, with the subsequent consolidation, 

 and thickening, of these peri-neural textures, while the 

 "weeping," so conspicuous in certain cases, may be said 

 to be due to the abnormally free discharge of the more 

 unmixed, and liquid, cerebro-spinal lymph. 



For three months longer the case under discussion con- 

 tinued to manifest the formation of spots and patches of 

 hyperkeratosis, at places over the surface areas primarily 

 affected, easily detected by touch, and mostly apparent to 

 the sight, along with irregular stretches of an-aesthesia, 

 par-aesthesia, or even kak-aesthesia (used to indicate an 

 absolutely "bad" feeling) in the distal distributions of 

 the implicated nerve fibres. In association with these 

 latter sensory phenomena, a limited motor paralysis of 

 certain of the extensor muscles of the left forearm took 

 place, leading to the production of fairly well-defined 

 " drop wrist," and the serious curtailment of the range of 

 movements required in everyday work. The explanation 



