214 



SECONDARY ELECTROMOTIVE PHENOMENA IN 



It is seen that the liminal strength for the appearance of positive 

 polarisation is very high, between 20 and 30 Groves, and the 

 primary descending current appears stronger than the ascending 

 one in the proportion of 112 : 100. The table also shows that in 

 the same strip, in proportion as its conducting power is exhausted 

 after repeated experiments, positive polarisation recedes and nega- 

 tive reappears. In the same proportion the difference in the 

 strength of the ascending and descending polarising current dis- 

 appears. 



The polarisability of the organ is reduced still more quickly and 

 completely to a mere trace, by boiling temperature, which at the 

 same time, as in muscle, lowers the resistance of the organ in a 

 remarkable degree, as, e.g., in an experiment not specially directed to 

 the observation of polarisation, in the proportion of 100 : 42. 



As stronger negative polarisation followed immediately, the 

 greater strength of the descending primary current in the boiled 

 piece had nothing to do with the preponderance which is observed 

 in the same direction in fresh pieces, but for some reason there was 

 a disturbance of reciprocity (see Sect. 10). That this preponderance 



