KUHNE'S IDIO-MUSCULAR PROOFS. 139 



fine fibres described by Beale, and which he rendered visible by 

 long soaking with all the parts in situ in glycerine of graduated 

 density.* It is plain that if Beale's anatomy of the muscular 

 nerves is right, the signification of Kiihne's experiments must 

 be entirely changed ; but it must be allowed that there are 

 some facts difficult to reconcile with the purely passive role of 

 the muscular fibre. Setting aside those resting on irritability 

 of a supposed nerveless portion, there are the contraction of a 

 small part when mechanically irritated, which does not spread 

 to the rest of the muscle supplied by the same nerve. I sup- 

 pose to this we may say that it is not known how small a por- 

 tion of the nerve may have independent sources of nerve 

 power. The fact that if the motor nerve trunks are paralyzed 

 with curare, no stimulus applied to or through them excites con- 

 traction, but if you electrify, or pinch, or bruise the muscle it- 

 self, it contracts. This may well be when we consider that 

 this poison is so specific in character that it has no effect on the 

 sensiferous nerves ; so it may also fail to act on the intra-mus- 

 cular nerve protoplasm, which is the source of power ; and, in 

 fact, Schiff found that irritation of a muscle whose nerve trunk 

 was paralyzed by curare re-acted beyond the point of contact, 

 and therefore he concluded that the nerve-ends were not 

 paralyzed. Again, the action of chemical irritants ; Kiihne 

 (590) adduces glycerine, creosote, lactic acid, and alcohol as 

 exciting the nerves violently, and, through them, the muscles ; 

 while, if applied directly to the latter, no action results. If 

 you apply glycerine to the cross section of the (supposed) 

 nerveless end, no contraction is excited, while if to the central 

 cross section, where nerves are, palpable jerkings follow. This 

 is, no doubt, from the fewness and fineness of the nerve fibres, 

 and the want of diffusive power of glycerine, for the experi- 

 ment succeeded only very imperfectly, if at all, with the 

 creosote, alcohol, and lactic acid, no doubt from their greater 

 power of diffusion into a region better supplied with nerve 



* Tergast, in his memoir on " The Relation of Nerves to Muscles," 

 in 1872, denies that any parts quite free from nerves exist (" Jaliresbe- 

 richt," 1873, p. 121). 



