Aprils, 1895.] 



SCIENCE. 



367 



tions based upon research in this fiekl con- 

 spire to indicate, if not to fully prove, that 

 the passage of the electric current along the 

 nerve is the initial act in the motion and 

 energy-production of the muscle. On the 

 other hand, however, it may probably be 

 stated, as conclusively ascertained, that 

 there is no representative of the mechan- 

 ism of our electro-dynamic machines, either 

 of generator or motor, in the muscle, 

 where, unquestionably, the applied en- 

 ergy is set free and utilized. There is no 

 equivalent of magnet, of solenoid, of field 

 or of armature. On the other hand, it is 

 indicated by numerous and varied investi- 

 gations and observations that the electric 

 current ha.s for its office, in the vital ma- 

 chine, the promotion of the chemical actions 

 wliich accompany all motion and develop- 

 ment of force and power. The familiar ef- 

 fects of currents having their origin outside 

 the body afford illustrations of the fact and 

 the method of action of these currents. 

 The electric currents, so far as existing in 

 the system, have light work to perform ; 

 and where, as in the gymnotus, they are 

 given more formidable tasks, they require 

 for their production and application very 

 large special organs, and occupj' an exorbi- 

 tantly large proportion of the body. 



The vital machine is probably not an 

 electro-dj-namic motor. 



(3.) The animal prime mover is very proba- 

 bly an example of an exceedingly highly organ- 

 ized and efficient chemieo-dynamic motor. 



There are but three known forms of en- 

 ergj' available in conversion of the stored 

 potential energj- of the foods into dynamic 

 form. Two of these have been seen to be, 

 the one certainly, the other probably, un- 

 utilized in the energA'-conversion of the vi- 

 tal machine. The third, until .some as j'et 

 undiscovered process and energy is found 

 to be available, must be assumed to be the 

 source of all dynamic phenomena in the 

 animal system. The machine is probably 



a chemieo-dynamic prime mover, in which 

 the developments of energy in active form, 

 their magnitude and their applications, are 

 directed by the supreme authority of the 

 system through a verj- perfect arrangement 

 of electric apparatus, bj' means of which the 

 necessarj' orders are telegraphed to the va- 

 rious points at which energy is to be liber- 

 ated and applied, and by the currents trav- 

 ersing which apparatus the chemical reac- 

 tions needed in transformation of the po- 

 tential energj' of the fats and glycose, and of 

 the products of broken-down tissue, into 

 active and useful form are inaugurated. 

 Electricity, or some related energy, serves 

 as the directing and stimulating power, and 

 the resolution of fats and other substances 

 into glycosic compounds and their oxida- 

 tion, at the point at which power is to be 

 developed, into carbon-dioxide and water, 

 by chemical changes resulting in the trans- 

 formation of potential into actual energies, 

 supplies the working power of the system. 

 The presence of electricity is always observ- 

 able in the vital machine, and the chemist- 

 physiologists have traced the processes of 

 supply and transportation of potential en- 

 ergj' and of the liberation of active energies 

 down to the very last, though still mysteri- 

 ous, act of utilization. 



These authorities are now apparently 

 substantially unanimous in declaring it 

 well settled that the action of muscle, for 

 example, is due to what is termed an ' ex- 

 plosive ' chemical action in the mass of the 

 organ, the outcome of which is mechanical 

 energy and the liberation of carbon-dioxide. 

 The physicist-physiologists are equally unit- 

 ed in testifying that the provocation of this 

 explosive action, at will and in proper 

 quantity, is effected by a nerve-impulse 

 which is more nearly like the electric cur- 

 rent than any other known form of physical 

 energy ; and the process of doing work by 

 muscular action is likened to the firing of a 

 charge of explosive in the mine by a current 



