108 APPENDIX I. 



considerable interest, as it shows that the difference 

 which, up to the time of Professor Helmholtz's 

 researches, had been admitted between the mode of 

 contracting of the striped and of the unstriped 

 muscles -is only one of degree. Of the latter 

 class of muscles, in contradistinction to the first 

 class, it was said that their contraction did not 

 immediately follow stimulation, and that their 

 energy rose, and subsided again, gradually. But it 

 is now obvious that all this holds equally with the 

 striped muscles, only that the whole process here 

 lasts but a few hundred ths of a second, whereas 

 with the unstriped muscles every stage of the con- 

 traction may take up as many seconds, so as to be 

 easily perceptible without artificial means. 



The values obtained in repeated trials for the 

 duration of the latent stimulation do not accord 

 very well ; but those which represent the tinie re- 

 quired by the muscle to raise an additional weight 

 remain almost identical as long as the muscle does 

 not become exhausted, provided the stimulation be 

 capable of producing the maximum of contraction 

 which can be called forth by instantaneous stimula- 

 tion. This also happens when, instead of stimu- 

 lating the muscle itself, the induced current, in 

 successive trials, is made to act with sufficient 

 energy upon always the same part of the nerve, only 

 in this case the time of latent stimulation is found 

 to be a little longer than in the case of the muscle 

 itself being stimulated. But on making the current 

 pass alternately through the part A of the nerve 

 nearer to the muscle, by means of the wires 3 and 4 



