NERVE FORCE AND ELECTRICITY. 161 



and then traverse the fibres." While the function of 

 the formation of this substance and the means of de- 

 composing it when -required, would still remain with 

 the true living matter, there is room here for subor- 

 dinate, merely chemical action in aid of the functions 

 of the living body as a whole, such as we see also in 

 the action of the digestive juices. It is possible, also, 

 here occurs a portion of the storing up of force-pro- 

 'ducing material, and that here also, and not within the 

 actual fibre, we have scope for some hypotheses such 

 as those of Traube and Hermann, which, however, need 

 not be gone into, especially as the last involves the 

 incipient formation of myosin, a proximate principle, 

 which certainly does not appear till after death, and is 

 the cause of rigor mortis. It is possible, also, that 

 some share in the formation of this chemical substance 

 may be taken by the protoplasm masses of the arterial 

 capillaries. 



Nature of the Nerve Force, and its Relation to Electricity. 

 Since the time of Galvani, the existence of the nerve and 

 muscle electric currents has been known. It has since been 

 ascertained with accuracy that in the living muscle and nerve, 

 during rest, a current is detected when connection is made be- 

 tween the cross section and the longitudinal surface of the 

 muscle or nerve : the electricity of the former being negative, 

 and that of the latter positive. Also two points at unequal 

 distances from the centre of the longitudinal surface are posi- 

 tive and negative towards each other, and a different position 

 of these poles is taken up when the section is oblique. Several 

 other minute points respecting the behaviour of animal elec- 

 tricity are also known, but as their signification is as yet quite 

 undetermined it is unnecessary to particularize them. As the 

 muscle is surrounded with moist conductors, these electric cur- 

 rents are continually brought into equilibrium throughout the 



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