278 



Dr. N. H. Alcock. 



[Nov. 9, 



These figures show that — 



(1) Nerves tested by Wheatstone's bridge show an apparent diminution of 

 resistance after CHC1 3 of about 15 per cent. 



(2) Nerve.s tested by the Kohlrausch method show no alteration of 

 resistance. 



The difference between the two methods is that any polarisation in the 

 nerve appears by the first as an added resistance. The figures in the first 

 column of A therefore represent resistance and polarisation, and the 

 conclusions follow — 



A. CHCI3 diminishes the polarisation of nerve ; 



B. CHCI3 does not alter the real resistance of nerve within the limit of 

 error of the method. 



If the diminution in the control experiments is taken as a correction to be 

 applied to the nerves, the resistance of these after CHC1 3 is increased by 

 1 per cent., at present it is doubtful if this correction is to be applied. 



- - [Note added December 12. — A fresh series of experiments (Nos. 211 

 to 214) gave the final ratio for nerves slightly less than the control threads. 

 The probable limit of error of the resistance experiments in the text is about 

 + 2 per cent., and as this lies in the object examined rather than in the 

 measurements, greater accuracy seems at present unattainable.] 



Series VI. 



Similar experiments were made with ether, taking readings by both 

 methods. The control threads now show a diminution of about 5 per cent, 

 and an increase during etherisation. Except in this latter particular the 

 nerves gave results almost identical with CHCI3. 



