CHEMICAL CONSTITUTION AND PHYSIOLOGICAL ACTION. 185 



any position. In twenty-four minutes, the respirations were very feeble and 

 shallow, and at the rate of twenty-four in the minute ; the rabbit was perfectly 

 quiet and flaccid ; and severe pinching of the skin excited only feeble reflex 

 movements. There was not the slightest appearance of muscular rigidity, nor of 

 starts, spasms, or even quivering movements. In forty-seven minutes, the respir- 

 ations were extremely weak and jerky, and at the rate of ten per minute, while 

 the sensibility of the conjunctiva and cornea had greatly diminished. In fifty-six 

 minutes, the respirations occurred only eight times in the minute, and no move- 

 ment of the eyelids could be excited by irritating the conjunctiva or cornea. 

 Exophthalmos was now markedly present. Death occurred in one hour and two 

 minutes after the administration of the poison. 



In the autopsy, the heart was found to be distended, and acting irregularly 

 and slowly. There was no appearance of rigor two hours after death. 



When administered by the stomach, twenty grains of sulphate of methyl- 

 morphium produced no effect on a rabbit. 



Our experiments with morphia confirmed the observations made by others, 

 which show that this alkaloid has two prominent actions on rabbits — a convul- 

 sant and a hypnotic one. We shall now consider how far each of these is modified 

 by the addition of sulphate of methyl to morphia. The addition of iodide of 

 methyl appears, no doubt, to have produced a very important change, but as 

 this is rather in the direction of diminishing, or, as our experiments indicate, 

 altogether destroying, the physiological activity of morphia, the iodide of methyl - 

 morphium may, in the mean time, be removed from consideration. 



It has been proved, in a most satisfactory manner, that sulphate of methyl - 

 morphium possesses no convulsant action; for neither in the experiments we 

 have described in detail, nor in any of the others we performed with this substance, 

 was there any trace of spasmodic action or of exaggeration of the reflex function. 

 It, however, undoubtedly causes hypnotic symptoms. In small non-fatal doses, 

 hypnotism was chiefly manifested, and this rendered it somewhat difficult to 

 judge whether paralysis were present or not. In large non-fatal doses, and in 

 fatal doses, on the other hand, paralysis appeared to be the chief effect, though 

 hypnotism was also present. It would, therefore, seem that sulphate of methyl- 

 morphium agrees with morphia in possessing a hypnotic action, but differs from 

 it in producing paralysis, and in being free from all convulsant action. It is 

 obvious that an objection might be urged against the latter part of this statement ; 

 for both the absence of convulsions and the production of paralysis might be 

 merely the effects of hypnotism. Though we were ourselves convinced, from 

 our experiments on rabbits, that such is not the case, we made some experiments 

 on frogs to determine this more clearly. 



Experiments CXV. and CXX — The blood-vessels were tied in one limb near 

 the knee of two frogs, selected because of their resemblance to each other in weight 



