63 



production of convulsions, is merely to increase nutrition in the 

 nervous centres. It is important for practitioners to know that 

 mode of action. The usefulness of strychnine in many cases of 

 palsy, may be explained very easily by that action. I have 

 frequently seen, in the wards of the hospital la Charite at Paris, 

 paralytics under the care of Dr. Rayer, taking strychnine. 

 Every day the reflex faculty was increasing in them as long as 

 they took that substance ; and on the contrary, when the use of 

 that medicament was stopped, the reflex faculty began immediately 

 to dimmish, and in some patients it disappeared. If strychnine 

 was given anew, the reflex faculty was still increased. These 

 facts have been recorded with great care by my learned friend, 

 Mr. Chareot. I hope he will publish them. 



From all the facts narrated in this paper, I believe I am enti- 

 tled to draw the following conclusions : 



1. The convulsing poisons, more particularly strychnine, 

 brucine, picrotoxine, cyanhydric acid, nicotine, morphine, cyanide 

 of mercury, sulphide of carbon, digitaline, oxalic acid, appear 

 to produce convulsions, without acting either directly or indi- 

 rectly on the muscles or on the motor or sensitive nerves. 



2. Generally these poisons do not appear to produce convul- 

 sions in acting directly on any part of the nervous centres. 



3. These poisons, in producing convulsions, act only on the 

 parts of the nervous system endowed with the reflex faculty. 



4. The mode of action of these poisons consists in the increase 

 of the nutrition of the nervous centres, by which excess of 

 nutrition the reflex faculty becomes much increased. 



XX. -ON THE CROSSED TRANSMISSION OF IMPRESSIONS IN THE 

 SPINAL CORD. 



Numerous experiments which I have performed have proved 

 to the numerous physicians and students, who have seen 

 the most important of them, that the impressions made on one 

 side of the body are transmitted to the sensorium by the oppo- 

 site side of the spinal cord. 



It is known that Galen* performed two experiments, which 



* See : De locis affectis, lib. iii. cap. xiv ; or De anatomicis admonstra- 

 tionibus, lib. viii. sect. 6. 



