62 



are no convulsions. We must consequently draw from these ex- 

 periments these two conclusions : 



1. Strychnine does not act upon the sensitive nerves. 



2. Strychnine acts upon the spinal cord. 



Now, from all the facts above related, two other conclusions 

 are to be drawn: 



1. Strychnine does not excite the nervous system ; or, in other 

 words, strychnine does not produce convulsions directly. 



2. Strychnine increases the reflex faculty of the spinal cord, 

 and so produces convulsions indirectly. 



I do not intend to examine here whether strychnine kills in 

 producing convulsions, or by another action. Nevertheless, I 

 will say, that although convulsions are sufficient to kill in 

 asphyxiating, death, in cases of poisoning by strychnine, may 

 be also produced by another action of that poison. I have seen 

 animals in which convulsions did not take place at all, and 

 which have been killed by strychnine. 



The other convulsing poisons that I have studied, appear to 

 act as strychnine, as to the production of convulsions. 



The same experiments which I have related as regards 

 strychnine, have been performed with these poisons, and I have 

 obtained the same results. Sometimes, nevertheless, I found 

 some differences ; and, for instance, it appears that the chloride 

 of barium is a direct exciter of the muscular fibres, and cyan- 

 hydric and oxalic acids seem also to be slight but direct exciters 

 of the spinal cord. 



The action of the chloride of barium is very important, be- 

 cause that poison is an exciter of the muscular fibres, and not of 

 the nerves. This fact proves that the muscular irritability may 

 be put in action without the intervention of the nerves. 



The increase of the reflex faculty, by the convulsing poisons, 

 is a very important fact. How is that increase produced ? We 

 believe it takes place in consequence of an increase in the nutri- 

 tion of the nervous centres. J. Mueller* is of opinion that 

 there is no substance able to increase directly the vital proper- 

 ties of any organ. He says that nutrition alone is able to pro- 

 duce such an effect. I believe he is perfectly right, and I ad- 

 mit that the mode of action of the convulsing poisons, in the 



* Manuel de Physiol., edited by Littre, 1851, t. i. p. 582. 



