CHEMICAL CONSTITUTION AND PHYSIOLOGICAL ACTION. 159 



cavities (twenty grains in all) of a rabbit, weighing three pounds and two and 

 a-half ounces. Fifty minutes afterwards, the animal was lying flaccid, and ex- 

 hibited the continuance of life only by slow and laboured respiratory movements. 

 In one hour, tremulous movements of the body and limbs accompanied the 

 respirations ; and it was extremely difficult to excite even a feeble reflex move- 

 ment by pretty strong stimulation. In one hour and ten minutes, the rabbit 

 was dea 1. 



The autopsy was immediately made : the heart was contracting with regularity 

 and considerable force, at the rate of 160 beats per minute ; the intestinal peristalsis 

 seemed normal ; galvanic stimulation of the exposed muscles caused energetic 

 contractions, and continued to do so until more than thirty minutes after death ; 

 and similar stimulation of the exposed sciatic nerves caused contractions of the 

 posterior extremities at four minutes after death, but ceased to do so in other five 

 minutes. 



These experiments are sufficient to illustrate the physiological effects that are 

 produced when iodide of methyl-strychnium is administered to rabbits by sub- 

 cutaneous injection. We have made similar experiments, with exactly analogous 

 results, on dogs and cats, the more important details of which are mentioned in 

 the table at the end of this paper. 



The effects of internal administration were examined by passing a gum-elastic 

 catheter down the oesophagus of a rabbit, and so injecting iodide of methyl-strych- 

 nium, suspended and dissolved in warm distilled water. It is unnecessary to 

 give any description of these experiments, at this place, as no effect was produced 

 by this method of exhibition, although as much as thirty grains was given at one 

 time, and it was inconvenient, as well as unnecessary, to give larger doses. It is 

 well known that to produce symptoms with a poison in a rabbit, a much larger 

 quantity is required when it is administered by the stomach than when it is 

 injected subcutaneously. The contrast between the action of iodide of methyl- 

 strychnium and strychnia itself was, however, well shown in the rabbit to which 

 thirty grains of the former had been given without any effect ; for one-tenth of a 

 grain of strychnia, also administered by the stomach, quickly produced violent 

 tetanic convulsions, and, in a few minutes, killed the animal. 



As iodide of methyl-strychnium is a sparingly soluble substance, it appeared 

 proper, in conformity with our fourth condition, and in order to compare the 

 actions of strychnia and of methyl-strychnium, that the properties of the sulphate 

 of the latter, which is extremely soluble, should be examined. 



Sulphate of methyl-strychnium ((C 21 H 22 N 2 2 CH 3 ) 2 S0 4 ) was prepared by precipita- 

 ting a hot aqueous solution of the iodide by a hot solution of sulphate of silver, 

 the slight excess of the latter was precipitated by chloride of sodium, the filtrate 

 evaporated to dryness, and the sulphate of methyl-strychnium extracted by 

 means of alcohol. It crystallises in delicate white needles, is very soluble in cold 



VOL. XX V. PART I. 2S 



