80 



Blair Bell 



the catheter is determined by the diameter of the animal's trachea, which 

 the catheter should never fit closely. The insertion of the catheter was 

 effected after the animal had been anaisthetised with ether by the ordinary 

 " open " method. 



Durino- the intratracheal administration of the ansesthetic the animal 

 rarely received pure ether vapour ; it was usually sufficient, once the 

 animal was fully anassthetised, to continue the anaesthesia with a mixture 



Fig. 1. — Apparatus for the administration of intratracheal ether. (Photograjih.) 



A, tube from bellows: B, three-way tap indicator: C. tube to ether container: D, ether container; 

 E, tube from ether container: F, tube to mercury pressure valve ; G, mercury pressure valve ; 

 H, pressure manometer; I, tube to catheter ; K, catheter. 



of air and ether vapour, regulated by means of a three-way tap to which 

 an indicator was attached (fig. 1, B). Bj^ this means ether, ether and air 

 mixed, or air alone could be pumped into the lungs under a uniform and 

 limited pressure. 



The anaesthetist sat at the side of the table opposite to the operator 

 with his hand underneath the coverintj cloth and restino; ao'ainst the side 

 of the animal, in order to judge of its condition: quiet, deep, and slow 

 respiration indicated perfect anaesthesia ; rapid, shallow breathing too deep 

 anaesthesia, while insufficient anaesthesia was shown by jerky and spasmodic 



