ox THE PHYSIOLOGICAL ACTION OF THE METHYL COMPOUNDS. OO 



exposure to the air, and the lungs always bloodless, white, and collapsed ; I 

 found, in fact, precisely the same state of things as occm-s when the medulla 

 oblongata is rendered inactive by extreme cold. The mean period of timo 

 during which the muscles respond to galvanism after death by chloroform 

 varies from twenty minutes to half an hour. The coagulation of the blood 

 is natural. 



The advantages of chloroform over other anaesthetics, so far known, are its 

 readiness of application, and the prolonged action of the ana3sthesia induced. 

 Its maiu disadvantage lies in its high boiling-point, and the consequent 

 amount of force required to eliminate it from the body. Indeed, according 

 to my experience it is never eliminated purely by the lungs, but by all the 

 excreting organs, so that any error or deficiency in those organs may lead to 

 such suppression of elimination that the nervous centres may become over- 

 whelmed, with consequent arrest of their activity. The 'temperature of the 

 air exerts a marked inlluence on the effects of chloroform in this respect of 

 elimination ; the influence of the anaesthetic being greatly prolonged when 

 the air is loaded with moisture and the thermometer is low. The best means 

 of restoration in impending death from chloroform is the introduction into 

 the lungs by artificial respiration of air heated to 130° Fahr. Under this 

 influence, in animals even with the chest Inid open, the heart is seen to leap 

 into instant activity and the arteries to recommence pulsation. In one expe- 

 riment this restoration of vascular motion was so distinct that the blood made 

 its way round the arterial circuit, the nervous centres regained power, and 

 the animal (a dog) may be said temporarily to have lived again. 



To fill the lungs with warm air for the purpose described, a small pair of 

 handbeUows connected with a tube of thin metal, in a coil, answers well. 

 With a spirit lamp the coil can be almost instantly made hot, and the air 

 passing through it with brisk force can easily be raised to 130° Fahr. It is 

 only necessary to inject the air through one nostril. 



Teteachlokide of Caeboi]-. 



Recently, the substance known as C Cl^ — the tetrachloride of carbon — 

 has been brought into use as a substitute for chloroform. In this body aU 

 the hydrogen elements of marsh-gas are substituted by chlorine, and it is 

 indeed the final result of the action of chlorine on that gas. It is a fluid of 

 not very pleasant odour; its boiling-point is 172° Fahr., its specific gra-\dty 

 is 1-600. As this substance is now gaining importance, I have thought 

 it proper to subject it to very careful experiment, and I feel it my duty to 

 state, both on theoretical and practical grounds, that it is more dangerous 

 than chloroform, and it' it were as generally used it would act fataUy in 

 a much larger number of cases. In its action it presents the same four 

 stages as chloroform, but the second stage is more prolonged and intensified. 

 In one animal (a rabbit) tetanic convulsion of an extreme character was 

 presented diuing this stage. But the worst feature in the administration 

 of this body is the slowness of its elimination, a slowness fuUy accounted 

 for by the boihug-point. Saturating the nervous centres, and expending 

 their force to the fullest, it kiUs far more quickly and determiiiately than 

 chloroform, and so completely is motion paralyzed that the muscles scarcely 

 respond to galvanism five minutes after dissolution. In order to make an 

 exact comparison (and it is from this comparison I draw the results arrived 

 at), I placed animals of the same kind, at the same time, at the same tem- 



