Electricity and Galvanism. 241 



electricity of muscular structures is owing to the mutual reaction of 

 an acid and alkaline fluid. Every one is aware that the blood, in a 

 healthy state, exerts a decided and well-marked alkaline action on 

 test-paper : now it is remarkable that although a piece of muscular 

 flesh contains so large a proportion of alkaline blood, still that when 

 chopped up, and digested in water, the infusion thus obtained is 

 actually acid to litmus paper. This curious circumstance is explain- 

 ed by the fact announced by Liebig, that although the blood in the 

 vessels of the muscle is alkaline from the tribasic phosphate of soda, 

 yet the proper fluids or secretions of the tissues exterior to the 

 capillaries is acid from the presence of free phosphoric and lactic 

 acids. Thus in every mass of muscle we have myriads of electric 

 currents arising from the mutual reaction of an acid fluid exterior 

 to the vessels on their alkaline contents. Whatever may be the 

 ultimate destination of this large quantity of electricity, it is at least 

 remarkable that a muscle should be really an electro-genic ap- 

 paratus. This view of Liebig on the condition of the fluid of 

 muscles curiously helps in explaining the presence of electricity 

 in them, announced by Matteucci. We have thus two sources of 

 the electricity of muscles — the effects of metamorphosis of effete 

 fibres on the one hand, and on the other the mutual reaction of two 

 fluids in different chemical conditions. It is certainly curious thus 

 to find a muscle, an organ long regarded as the motor apparatus of 

 the bony levers of our frames, invested with new properties. Its 

 agency in generating electricity can no longer be denied, and I hope 

 by and by to render it probable that the seat of the generation of 

 animal heat is also in the muscles. In the course of twenty-four 

 hours, a considerable proportion of watery vapour exhales from the 

 surface of the body. This has been variably estimated, and in all 

 probability is liable to great variation, but from thirty to forty-eight 

 ounces of water may thus be got rid of from the system. The 

 evaporation of this amount of fluid is sufficient to disturb the electric 

 equilibrium of the body, and to evolve electricity of much higher 

 tension than that set free by chemical action. A metallic cup, 

 containing a few drops of water, is placed on the electrometer before 

 me. I now drop in a piece of hot charcoal ; a cloud of watery 

 vapour is evolved, and the gold leaves instantly diverge to their 



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