200 SECONDARY ELECTROMOTIVE PHENOMENA IN 



In the general interest it would indeed have been better if I had 

 at once told Hermann that positive polarisation prevailed in the in- 

 trapolar tract. The course of science in this direction would have 

 been different, and perhaps more fruitful. 



A year later Hermann brought forward his hypothesis anew, 

 somewhat more carefully worked out ; after having made use of 

 some of the hints contained in my confutation ; he this time made 

 a point of supporting his electrotonus theory by experiments 1 . ' The 

 battery consisted of from a to 6 very small Daniells ; the nerve- 

 current was always accurately compensated to zero before the passage 

 of the current. The passage of the current lasted, on an average, 

 for a minute.' Under these circumstances Hermann naturally suc- 

 ceeded in seeing nothing but negative polarisation in the intrapolar 

 tract. As this result appeared to agree with his hypothesis that 

 1 the splitting of the nerve-molecules is quickened by the kathode 

 and retarded by the anode,' and as it appeared to contradict my 

 molecular theory, he was satisfied to hold by it. 



Hermann's experiments also embraced the extrapolar tracts with 

 which Adolph Tick had occupied himself after Matteucci 2 . He 

 and Hermann arrived finally at the same conclusion, though the 

 latter really has the priority, inasmuch as Pick's first communications 

 did not correctly represent the facts. These are in Hermann's 

 words, 'Both the extrapolar tracts act for a short time after 

 the current is broken, and both are directed away from the tract 

 in which the current flows ; ' but the anelectrotonic after-current 

 which is opposed to the polarising current is the stronger of the 

 two 3 . 



In the meantime, Hermann allowed his hypothesis upon the 

 different ' rapidity of splitting ' (Spaltungsgeschwindigkeit) as the 

 cause of the electrotonic current, to drop, and took up in its place 

 Matteucci's above-mentioned explanation of the extrapolar elec- 

 trotonic current by diffusion, the complete verification of which 

 he made his chief task. His experiments on intrapolar negative 

 polarisation served him now as a proof of Matteucci's hypothesis 4 , 



1 Untersuchungen zur Physiologic der Muskeln und Nerven, Drittes Heft, Berlin, 

 1868, pp. 71 ff. 



2 Centralblatt fur die medicinischen Wissenschaften, 1867, p. 436 ; Untersuchungen 

 aus dem physiologischen Laboratorium der Zuricher Hochschule, parti, Wien, 1869, 

 p. 129. 



3 Handbuch der Physiologic, vol. ii. p. 164. 



4 Pfliiger's Archiv fur die Gesammte Physiologic, 1872, vol. vi. p. 357 ; Handbuch 

 der Physiologic, vol. ii. pp. 164, 165. 



