APPENDIX I. 117 



tive action of the nerve,* and, as afterwards demon- 

 strated chiefly by Professor Pfliiger, also by a 

 change in the excitability of its different points, j 

 These changes, which only last as long as the 

 current itself, are found to be the more considerable 

 the nearer to the electrodes the nerves are examined. 

 In addition to these facts, Professor v. Bezold found 

 the velocity of the nervous agent to be diminished 

 in the electrotonic state, and that also the more, the 

 nearer to the electrodes the nerves were examined. 

 These researches were made with the speaker's im- 

 proved rotating myographion, alluded to above. 

 (See p. 113.)} 



Rate of Transmission of Sensation in the Nerves 

 and the Spinal Cord of Man. All the preceding 

 experiments were made upon the motor fibres in the 

 sciatic nerve of the frog. Similar results, however, 

 have been arrived at with regard to the nerves of 

 sensation in the living body of man, in the following 

 way. 



An induced current is made to impinge alternately 

 upon two different places on the skin, so as to cause 

 just a slight sensation of pain. The two places 

 should be such as are supplied, like the big toe and 

 the inguinal region, for instance, with sensory fibres 



* UntersucJiungen iiber thierische Elektricitdt, Bd. ii., Abth. i. 

 Berlin, 1849, S. 289. On Animal Electricity, &c., by H. Bence 

 Jones. London, 1852. P. 174. 



t Untersuchungen uber die Physiologie des Electrotonus. 

 Berlin, 1859. 



J A. v. Bezold, Untersuchungen uber die eleldrische Erregung 

 der Nerven und Muskeln. Leipzig, 1861. 



