112 ELECTRO-PHYSIOLOGY CHAP, 



to keep up this state. On breaking the current, the nerve almost 

 immediately recovered its conductibility. Under these conditions 

 Wedenski was unable to detect any fatigue in nerve at the point 

 of stimulation, even after six hours' excitation. Maschek (70), 

 who confirmed the experiments of Wedenski, succeeded in pro- 

 longing the experiment for twelve hours, without any perceptible 

 fatigue of the point of stimulation. Maschek further showed by 

 means of local ether-narcosis, which of course implies rapid 

 recovery, that an excitation lasting many hours produces no 

 visible fatigue at the point excited. Bowditch (70) arrived at 

 the same conclusion in warm-blooded animals (cats) by means of 

 curare, the effects of which are soon dissipated (cf. also Szana, 70). 

 "When the action of curare has quite worn off after persisting 

 three to four hours, the induction current, which has been passed 

 uninterruptedly through the peripheral end of the muscle during 

 the action of the poison, resumes its full effect." 



The fact that nerve may be excited for many hours without 

 perceptible fatigue suggests, as remarked by Bowditch, the idea 

 that excitation may be transmitted ivithout consumption of material. 

 In view of certain facts to be considered later, it is, however, 

 more accurate to say that a certain expenditure of nervous 

 energy is consumed (even if it cannot be measured experi- 

 mentally) in the mere propagation of the excitation. 



BIBLIOGRAPHY 



1. ALBRECHT. Biolog. Cbl. VI. 1887. Nr. 23. 



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Abth. p. 9 ff. 



4. KOLLIKER. Handb. d. Gewebelehre. II. (And other literature of the histology 



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