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to the pulse as an indication of the stage of narcotism ; a few subse- 

 quent experiments confirmed the opinion ; and I have not since hesi- 

 tated to push etherization to complete insensibility, and to continue 

 it, if necessary, during a length of time, provided the pulse remained 

 full and strong. If it be retarded, it is curious to observe with what 

 certainty it recovers force and frequency, after a few inspirations of 

 pure air. It will be inferred from these remarks that the pulse is 

 to be carefully examined during the whole anaesthetic process, and 

 that inhalation is to be temporarily discontinued at its indication. 



Briefly to recapitulate, the first insensibility, partial though it be, 

 suffices for the dentist. It exhibits the intellect and sensibility in 

 novel and singular relations ; while muscular force may or may not 

 be impaired. Nothing is here infallible in pulse or pupil. 



The second stage is of great value, and often essential to the sur- 

 geon. It lies between the signs of returning consciousness on the 

 one hand, and the decreasing pulse on the other. It is ultimately 

 accompanied by snoring inspiration, and the partially dilated pupil ; 

 which, together with the period of time necessary for the cumulative 

 effect of ether, may be considered, each, as an additional indication 

 for the temporary suspension of inhalation. 



Sigyis of Narcotism. — The eyes are usually closed during inhala- 

 tion. Let the patient be directed to open them. If etherized, he 

 takes no notice of the voice. Perhaps the head droops ; or the hand 

 supporting the inhaling apparatus falls. •' These, alone, are signs of 

 narcotism, which may be incomplete ; or, if complete, temporary in 

 its duration. If, in such a case, the arm of the patient be raised 

 from his side, it is quite likely to resist the effort ; or when raised, 

 remains extended; phenomena indicative of partial narcotism. If 

 inhalation be now suspended, the patient soon regains his con- 

 sciousness ; either manifesting unequivocal signs of pain, or resisting 

 interference, during the half conscious state which often precedes 

 recovery. 



It should be added, that if the patient has inspired a good dose, 

 and for a length of time, the dentist may consider any unusual 

 manifestation, as an indication of but partial sensibility to sudden 

 pain ; protracted inhalation may be even taken as its priori evidence. 



One of the early and occasional consequences of inhalation is a 

 passive cessation of the respiration, while the pulse continues good. 

 At this moment a tooth may be painlessly extracted; but as the 

 vapour has now temporarily ceased to gain access to the lungs, the 

 patient may revive before the next inspiration. 



