ON THE MAMMALIAN NERVOUS SYSTEM. 511 



CHAPTER XII. ON THE ELECTRICAL CHANGES EVOKED IN THE SPINAL CORD 

 AND NERVES BY THE ACTION OF ABSINTHE AND STRYCHNIA. 



SECTION 1. EXPERIMENTS (CONTROL) INCLUDING THE USE OF ABSINTHE. 



Very early in the present investigation on the effects produced by electrical excita- 

 tion of central apparatuses, the advisability of obtaining a control of our results 

 presented itself. The use of strychnia by DU BOIS-REYMOND as a control demon- 

 stration of the excitatory electrical state in nerves, formed, as it always must, the 

 basis of such a method. 



We, however, first selected absinthe as particularly exciting nerve centres, and, 

 according to one of us* (V.H.), specially the cortex. Absinthe has been known since 

 the experiments on animals by MARCEt to cause, in small doses, effects only explicable 

 as poisoning of the highest cerebral centres, thus producing mental changes, delirium, 

 hebetude, &c., while in larger doses it evokes clonic epileptiform convulsions with 

 stertorous respiration, &c. 



MAGNANJ has, of all writers, contributed the most to our knowledge of the action 

 of this substance. 



By injecting small quantities of the essence of absinthe either into the stomach or 

 into a vein, he produced a very striking series of phenomena, which he showed were 

 identical with idiopathic epilepsy. 



Following up its action more closely he endeavoured to ascertain the share taken in 

 the production of the fits by the brain and spinal cord respectively. This he investi- 

 gated by first dividing the cord at the atlanto-occipital articulation, and then injecting 

 absinthe, artificial respiration being kept up. 



Unfortunately, he only describes one experiment (No. 6) in which the cord was 

 completely divided. He concludes, however, from his other experiments that the 

 drug excites simultaneously the lower (spinal) and the upper (cerebral) centres. It 

 has, however, been shown by one of us that complete section of the cord at the 

 8th dorsal vertebra pi-events the appearance of the characteristic convulsions in the 

 muscles of the parts below the level of the section ; and, further, that the corresponding 

 parts or limbs, if the excitable cortex of one side be removed, will not take part in 

 the first general epileptiform convulsions which follow the injection of the drug, 

 whilst, even when in the subsequent fits such parts are affected, the muscles only pass 

 into a slight degree of tonus. 



Until a more extended series of researches should negative these points, it is 



* ' Brown Lectures." 



f ' Comptes Rendns de 1' Academic des Sciences,' vol. 58, 1864, p. 628 ; also AMORY. 



J ' Recherches sur Ics Centres Nerveux,' Paris, MANON, 1876. 



'Reports of tbc Brown Institution.' 



