CHEMICAL CONSTITUTION AND PHYSIOLOGICAL ACTION. 189 



describe the effects that are produced by nicotia itself, — and in order to obtain as 

 exactly comparable data as possible, a portion of the nicotia used in the prepara- 

 tion of the iodide of methyl-nicotium employed in Experiments CXXVII. and 

 CXXVIIT. was administered to the rabbit which recovered from fifteen grains of 

 the latter substance. 



Experiment CXXXII. — One half-minim of nicotia (about 0-5 grain) was dis- 

 solved in fifteen minims of very dilute sulphuric acid, and the solution was 

 injected into the subcutaneous cellular tissue of the rabbit employed, a week pre- 

 viously, in Experiment CXXVII. Symptoms were rapidly produced. In two 

 minutes, spasmodic contractions occurred in the four limbs, which became 

 extended, and raised the body in a convulsive manner. In three minutes, violent 

 tremors occurred, and the whole body was convulsively agitated. In a few 

 seconds afterwards, the limbs altogether yielded ; the rabbit lay on the abdomen; 

 and strong twitches occurred in the muscles of the neck, by which the head was 

 jerked upwards, and in the limbs, by which the body was partially raised. This 

 condition continued until ten minutes, when the spasmodic twitches ceased, and 

 the rabbit fell on the side. It was now perfectly flaccid, with only twenty-five 

 laboured respirations in the minute. In fourteen minutes, the respiratory 

 movements were so feeble as to be scarcely visible ; and, in fifteen minutes, they 

 altogether ceased. 



In the autopsy, the heart was round contracting, five minutes after death, at 

 the rate of 160 per minute, but its contractions were feeble. The vermicular 

 movements of the intestines appeared to be normal. The trunk of a sciatic nerve 

 was irritated, ten minutes after death, and energetic movements followed in the 

 limb to which the nerve was distributed. 



Having found, in the case of iodide of methyl-nicotium, that so large doses of 

 an extremely soluble substance were necessary to affect a rabbit by subcutaneous 

 injection, we did not consider it advisable to determine how much was required 

 to produce symptoms when it is exhibited by the stomach. For it may be almost 

 positively asserted that, in the latter case, a much larger dose would be necessary; 

 and while the administration of this would be inconvenient, because of its bulki- 

 ness, and of the difficulty of obtaining a large quantity in a perfectly pure form, 

 the data obtained by subcutaneous injection are sufficient to prove the principal 

 change that the addition of iodide of methyl produces in the physiological action 

 of nicotia — namely, a great diminution in its poisonous activity. 



Sulphate of methyl-nicotium (C 10 H 14 N 2 (CH 3 ) 2 SO 4 ) was prepared by precipi- 

 tating a solution of the iodide by means of sulphate of silver. It forms a white, 

 crystalline mass, extremely soluble in water. 



On account of the readiness with which iodide of methyl-nicotium dissolves 

 in water, it was not to be expected that any change in poisonous activity would 

 be caused by its conversion into a sulphate ; and the following experiment con- 



