KATHODIC POLAKISATION OF MUSCLE. 333 



support for the theoretical conception of the secondary electromotive 

 phenomena of the smooth muscle of Anodonta, and especially of 

 positive kathodic polarisation in it, by the investigation of objects 

 better suited to the purpose. 



As there is such a regretable want of suitable organs with 

 smooth muscles, experiments on the heart, especially of inverte- 

 brate animals, seemed at first to promise a good result ; they fail, 

 however, chiefly on account of the small size of the object. The 

 heart is moreover very little suited for experiments on polarisation 

 by reason of the complicated course of the fibre. Thus the only 

 thing left was to consider the possibility of artificially putting 

 striated trunk muscles into a continuous condition of excitation, 

 lasting for a sufficient time, and comparable to the ' tonus ' of 

 certain smooth muscles, and during this condition to investigate 

 the changes of form resulting on electrical excitation on the one 

 hand, and the secondary electromotive phenomena on the other. 

 I have endeavoured to attain this end by poisoning with veratrine, 

 and I will communicate the results of my experiments in this matter 

 on the sartorius muscle of the frog, in the following paragraphs. 



I must not omit to mention here, that at the suggestion of 

 Professor Hering, I made experiments several years ago, upon the 

 effect of electrical stimulation on muscle's in persistent contraction ; 

 although I had repeatedly succeeded at that time, by closing an 

 electrical current, in producing a perceptible relaxation in muscle 

 preparations which had been previously put into persistent con- 

 traction by the action of vapour of ammonia, yet the results seemed 

 too uncertain to permit of making further deductions from them. 



2. Changes of form which muscle poisoned by veratrine 

 undergoes when excited by a battery current. 



Since von Bezold 1 first determined accurately the remarkable 

 effects of veratrine upon striated muscle, they have been repeatedly 

 the object of detailed investigations. Their main result is the 

 theory that the extremely striking after-effect produced by every 

 stimulus, however short its action, is founded solely on a changed 

 condition of the substance of the muscle itself, and as Fick 2 thinks, 



1 'Unters. aus d. Wiirzburger Laboratorium,' 1867. 



2 ' Arbeiten aus d. pbysiolog. Laboratorium der Wiirzburger Hochschule,' ii. Lief- 

 erung, 1873, p. 142 f. 



