512 MESSRS. F. GOTCH AND V. HORSLEY 



reasonable to accept the conclusion that absinthe excites par excellence the complex 

 cortical centres. 



It will be well, perhaps, to mention that by the method of simple observation the 

 following phenomena are elicited by the excitatory action of absinthe. 



After injection of two drops of essence of absinthe* into the jugular vein of an 

 animal, narcotised with, ether to the degree of unconsciousness, there occur, after a 

 sufficient interval has elapsed (30 seconds or so) to permit of the translation of the 

 poison through the heart and lungs to the arterial system, and so to the brain, the 

 following events : 



The small facial muscles begin to twitch in single clonic spasms, next passing into 

 a state of tremulous tonic spasm. This order of convulsion passes rapidly down the 

 body, until the tonic spasm in the limbs is extremely marked. After this has 

 obtained for a period varying with the dose injected, the tonic spasm gives way to a 

 long series of clonic twitches. Accompanying these motor " discharges," there is 

 profuse salivation, and sometimes escape of urine, while in cases in which narcosis 

 has not been preliminarily employed, unconsciousness and coma are early symptoms. 



It is thus obvious that absinthe affords a very simple and efficient means of 

 chemical excitation for the purpose of testing the validity of the results of electrical 

 stimulation of the motor cortex. 



We have employed it under the following experimental conditions : 



(1.) Connecting the nerve to the galvanometer or electrometer. 



(2.) Connecting the spinal cord to the galvanometer or electrometer, at the same 

 time observing the contractions of the muscles in different parts. 



The method employed was, so far as the electrical connections of the observed parts 

 were concerned, precisely that described in the preceding pages. Special precautions 

 had to be taken against any agitation of the preparation. The narcosis with ether 

 being temporarily maintained, the external jugular vein of either side was exposed, 

 penetrated by the needle of a hypodermic syringe, and two minims of the essence of 

 absinthe injected, the narcosis of this drug taking the place of the etherisation, 

 which was forthwith terminated. It was invariably observed that the galvanometer 

 showed evidences of excitatory electrical changes in either nerve or cord, before the 

 muscular contractions in the immediate neighbourhood of the observed level became 

 accentuated. 



In respect of what has been said above, we may here add that we never saw con- 

 tractions of muscles innervated from points below the level of section in the spinal 

 cord when that was divided. 



* Obtainable of Messrs. HOPKIN and WILLIAMS. 



