32 



CANINE AND FELINE SURGERY. 



allows a stream of air to be forced through a quantity of 

 chloroform, and so sends into the mask the vapour of air and 

 chloroform mixed (Fig. 15). 



With this it has been estimated that (at a temperature of 

 62" Fah.) with eight drachms of chloroform in the bottle, each 

 full compression of the bellows sends over an average of one 

 minim of chloroform vapour well mixed with air, in the pro- 

 portion of 1-869 ps'' cent. This apparatus is suitable for large 

 dogs, but with small ones and cats great care must be exer- 

 cised, or an overdose may easily be given. When used for these 



Fig. 15. 

 Diagram of Junker's inhaler (Krbhne & Sesemann's pattern). 



animals the bellows must not be compressed to their fullest 

 e.Ytent, and the end of the mask must be left open. 



The anaesthetist should commence by pressing the ball very 

 lightly, and not to more than about one-sixth of its extent, 

 the pressure being gradually increased until sufficient vapour 

 has been given to produce anaesthesia. 



The third pattern of apparatus plays a medium part between 

 the other two, as its object is to force a current of air over the 

 surface of the chloroform (Fig. 16). 



The vapour sent over is stronger than that of the first pattern, 

 but less concentrated than that of Junker's. 



