ELECTKICITY ONLY A STIMULUS ? 163 



reasoning, as we have seen, p. 127, and also on the 

 action of electricity itself on the nerves and muscles. 

 This last is a wide subject, and one for which a volume 

 would scarcely suffice; so I will not touch upon it 

 further than to notice that, besides the difficulties of 

 the electric actions which are merely physical, and 

 would take place in any moist, imperfect conductors 

 we have its action as a stimulus, and the whole forms 

 a complexity so great that little practical knowledge 

 has as yet been gained. 



One thing, however, must be noticed, viz., that by 

 Beale's theory the question is put on a different foot- 

 ing, for the muscular fibre is put out of account as the 

 recipient of a stimulus, and the nerve protoplasm alone 

 has to be considered directly, and when we speak of 

 irritability it is only of the nerve protoplasm. 



The action of electricity is thus to stimulate, as any 



theory ("Nature," Jany., 1872). He holds that muscular contraction, 

 whether in ordinary muscular contraction or in rigor mortis, is nothing 

 more than the result of the operation of the elasticity of the muscle 

 upon the discharge of the charge of static electricity which had pre- 

 viously kept up the state of relaxation. That the two opposite charges 

 are disposed Leyden-jarwise upon the two surfaces of the sheath, and 

 cause elongation of the fibre by compressing between them the elastic 

 sheath, and the contraction of the fibre follows the discharge of these 

 charges by the operation of the elasticity thvis brought into play. 

 This theory is so totally opposed to what is here held respecting the 

 nature of rigor mortis, and of the sarcolemma, and the fibre, &c., that 

 it is unnecessary to go into it at length. It has recently been found by 

 Dr. B. Sanderson that there is an electrical current from the proximal to 

 the distal end L of the living leaf of the Dionaea muscipula. If a fly 

 creeps in to the sensitive hairs and causes the leaf to close on it, the 

 needle swings to the right, showing the negative variation. The author 

 adds, "But it is to be borne in mind, that although when the muscle 

 or leaf contracts, electro-motiYe force disappears and work is done, there 

 is no reason for supposing that there is any conversion of the one into 

 the other, or that the force exercised by the organ is electrical' 

 (" Nature," June 18, 1871). 



112 



