446 Mr. J. S. R. Russell. Circumstances under which [May 18, 



"V*. The Action of Intravenous Injections of Absinthe and Strychnia. 



1. Absinthe. — The action of this drug on the lumbar centres was 

 tried, both when the spinal cord was intact and after transverse 

 section of it in the mid- dorsal region. As has been explained, a 

 jugular or femoral vein was exposed, and varying doses of the essen- 

 tial oil of absinthe were injected into it, according to the class of 

 animal under observation and the particular effect which was aimed 

 at. Doses short of those necessary to evoke generalised convulsion 

 were attended by increase of the knee jerk, whether the cord was in- 

 tact or divided in the dorsal region. Doses sufficiently large to evoke 

 powerful generalised convulsions were also followed by increase of 

 the knee jerk after the convulsions ceased.* 



When the spinal cord had been previously divided transversely in the 

 dorsal region, and the lower extremities thus excluded from the other- 

 wise general convulsions, the increase of the knee jerk, after large 

 doses of absinthe, was still observed. The increase never amounted 

 to clonus or tonus, but was nevertheless well marked. This effect of 

 absinthe on the lumbar centres was strikingly demonstrated in the 

 following experiment. The spinal cord of a dog was divided trans- 

 versely in the mid- dorsal region when the animal was so profoundly 

 under the influence of ether that the knee jerk could not be obtained. 

 The animal was then kept lightly under the influence of the anaesthe- 

 tic, but, in spite of this, the knee jerk had not returned fifteen 

 minutes after the cord had been divided. Three minims of the 

 essential oil of absinthe were then injected into the femoral vein of 

 one side, and the knee jerk of the opposite side kept under observa- 

 tion. "Well-marked convulsions occurred in a few seconds, limited to 

 those parts above the spinal cord lesion, while the parts below the 

 lesion remained inactive. At the time that the convulsions above 

 the cord lesion were at their height there was doubtful evidence of 

 return of the knee jerk. As there was absolutely no sign of the 

 presence of the knee jerk ten minutes after the first injection of 

 absinthe was given, 2 minims more of the essential oil were injected 

 into the same vein. As before, convulsions occurred in those regions 

 whose nerve supply was derived from the central nervous system 

 above the lesion in the spinal cord, while those regions which derived 

 their supply from below this point remained passive. A few seconds 

 after this further administration of the drug there was undoubted 

 return of the knee jerk, which persisted for a minute or two and then 

 disappeared. Ten minutes after the second dose of absinthe was 

 given a third dose of 2 minims was injected into the same vein as on 

 the two former occasions with exactly similar results with respect to 

 the convulsions. The knee jerk was obtained a few seconds after the 



* Beevor, loc, ext. 



