CHEMICAL CONSTITUTION AND PHYSIOLOGICAL ACTION. 



191 



thirty-nine minutes, irritation of any portion of the skin was followed by feeble, 

 but nearly equal, movements of the four limbs. The observations were now 

 interrupted. On the following morning the frog was jumping about normally. 



Experiment CXXX1. — The blood-vessels were tied at the right knee of a frog, 

 weighing 630 grains, and three grains of iodide of methyl-nicotium, dissolved in 

 twenty minims of distilled water, was injected into the abdomen. In twenty-six 

 minutes, the frog was lying, flaccid, on the abdomen and chest ; and when the 

 skin was irritated, reflex movements of equal strength were caused in the four 

 limbs. In one hour and sixteen minutes, the flaccid state had become more 

 marked, and, now, a somewhat stronger irritation was requisite in order to cause 

 reflex movements, while these appeared to be of greatest strength in the right 

 posterior (non-poisoned) limb. In two hours and forty-six minutes, the condi- 

 tion was exactly the same as last noted. The observations were now inter- 

 rupted ; and on the following morning the frog was found dead, and in rigor. 



We obtained similar results with the sulphate. 



It would, therefore, appear that though the convulsant effects of nicotia are 

 not produced by its methyl derivatives, these derivatives do not possess any 

 paralysing action on motor nerves. The change that is produced in the physio- 

 logical action of nicotia is not the same as that which we have described in 

 strychnia, brucia, thebaia, codeia, and morphia. We are inclined to believe, on 

 account of this difference, that the convulsions of nicotia are not due to the same 

 cause as in the other alkaloids we have examined. 



A great diminution in physiological activity has, however, been produced by 

 this chemical addition, and this will be at once recognised by referring to the 

 following table: — 



No. of 

 Experiment. 



Substance 

 employed. 



Animal and its 

 weight. 



Method of 

 exhibition. 



Dose. 



Effect. 



CXXVII. 



Iodide of methyl- 

 nicotium. 



Rabbit, 3 lbs. 



Subcutaneously. 



15 grs. (contain- 

 5'4 grs. of ni- 

 cotia). 



Trembling in 11 minutes, 

 and partial paralysis in 

 30 minutes ; these con- 

 tinued for about 49 and 

 50 minutes respectively, 

 and a perfect recovery 

 afterwards occurred. 



CXXXII. 



Nicotia (as sul- 

 phate). 



Do. (same rabbit 

 as in Experi- 

 ment CXXVII.) 



Subcutaneously. 



0*5 min. (0.5 gr. 

 nearly). 



Convulsions in 3 minutes, 

 and partial paralysis in 

 less than 4 minutes ; fol- 

 lowed by death, 15 min- 

 utes after administration. 



CXXXIII. 



Sulphate of me- 

 thyl-nicotium, 



Do., 4 lbs. 3 oz. 



Subcutaneously. 



10 grs. (contain- 

 ing 5 - 6 grs. of 

 nicotia). 



Trembling in 10 minutes, 

 slight paralysis in 20 

 minutes ; perfect recov- 

 ery in 1 hour and 20 min- 

 utes after administration. 



VOL. XXV. PART I. 



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