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state will readily be recognized; the first embracing the phenomena 

 of partial consciousness, while the second presents the indication 

 of total insensibility. 



These two stages of anaesthesia demand separate consideration. 



First Stage. — The first stage is characterized, either by the 

 incomplete or partial character of the narcotism or by its brief 

 duration. These phenomena suggest the notion that the blood is 

 insufficiently impregnated with ether, or that the vapour has affected 

 a portion only of the circulating fluid, the influence of which upon 

 the brain is soon counteracted by the arrival in the cerebral ves- 

 sels of fresh and unadulterated blood. Such theory illustrates the 

 degree and the duration of the phenomena attending such inebria- 

 tion. 



The first stage requires for its induction a comparatively small 

 proportion of the ether vapour. Insensibility, if complete is brief, 

 and the patient revives in a period varying from one to three mi- 

 nutes, commonly without nausea, headache, vertigo, or other sensa- 

 tions of discomfort. But in certain cases, and especially when 

 either from pulmonary irritability, or want of determination on the 

 part of the patient, the dose has been insufficient, and its inhalation 

 by consequence protracted through a period of six or eight minutes, 

 a different range of symptoms is presented. The patient may be 

 bewildered, like a man waking from a deep sleep, or uncontrollable 

 except by moderate coercion. At this time the pulse is natural, 

 or yet more frequently accelerated, either from exertion, or per- 

 haps it has not regained its normal standard after the unavoidable 

 excitement of anticipation. Though in the first stage of anae- 

 sthesia we might expect the pulse to be accelerated, yet it often 

 deviates but little from its natural standard. Nor is the pupil espe- 

 cially affected in this stage. The muscular fibre is yet animated by 

 the nervous influence, and is generally somewhat rigid; the arm re- 

 sisting flexion or extension. Occasionally it exhibits the phenomena 

 of catalepsy, retaining any position given to the limb. In rare 

 cases I have noticed the access of clonic spasm, local or general in 

 its invasion. When the spasm affects the glottis, it gives rise to a 

 peculiar symptom, to be alluded to hereafter. 



To the first stage of anaesthesia belong those remarkable and un- 

 anticipated physiological phenomena, which seem to unlink the inti- 

 mate connection between sensation and an intellectual recognition 

 of it; between cognizance and memory; between will and action. 



