308 



Dr. A. D. Waller. 



[Mar. 12, 



March 12, 1896. 



Sir JOSEPH LISTER, Bart., President, in the Chair. 



A List of the Presents received was laid on the table, and thanks 

 ordered for them. 



The Right Hon. Sir Richard Temple, a Member of Her Majesty's 

 Most Honourable Privy Council, wa8 balloted for and elected a Fellow 

 of the Society. 



The Croonian Lecture was delivered as follows : — 



Grooxian Lecture. — " Observations on Isolated Nerve. Elec- 

 trical Changes a Measure of Physico-chemical Change." 

 By Augustus D. Waller, M.D., F.R.S. 



(Abstract.) 



The present investigation arises from experiments undertaken to 

 determine autographicalry the varying relations between the magni- 

 tude of electrical change and the magnitude of stimulation in nerve 

 under various chemical conditions.* 



The main principle upon which the inquiry is based is the proposi- 

 tion established (by dn Bois-Reymond, and by Hermann in particular) 

 to the effect that disturbed protoplasm is electro-negative to the 

 normal. Am accessory principle to which reference will also be 

 made, is that upheld (by Hering in particular) to the effect that 

 protoplasm in which disturbance has just ceased is electro-positive 

 to the normal. 



In accordance with the first principle, injured is electro-negative 

 to normal protoplasm, and excited is electro-negative to resting proto- 

 plasm. 



In accordance with the second principle, recently excited is electro- 

 positive to normal protoplasm. 



Nerve (the excised and still-living nerve of the frog) is, for the 

 purpose of this inquiry, considered as a convenient strand of excit- 

 able yet hardly exhaustible protoplasm, giving off to the galvanometer 

 a demarcation or injury current (Hermann) from a less disturbed 

 portion (longitudinal surface L) to a more disturbed portion (trans- 

 verse section T), which current, during disturbance of the whole 



* ' Physiol. Soc. Proc.,' June, 1895. 



