24 CANINE AND FELINE SURGERY 



either as draught, intravenously, or b}' enema, are largely 

 made use of on the Continent as narcotizing agents to keep 

 the patient quiet and to deaden pain. 



Local Anaesthetics. 



Taking the local anaesthetics first, anaesthesia produced by 

 the first five agents mentioned (viz., cold water, ice, ether, 

 anestile, and ethyl chloride) depends chiefly upon the amount 

 and intensit)- of the cold produced. 



Cold water and ice have a very transient effect, and are 

 only suitable for trivial operations, such as the lancing of 



abscesses or the removal of small superficial tumours. In 

 order to act efficiently, they must be applied for a few 

 minutes directly to the part upon which the operation is to 

 be performed. 



In ether and ethyl chloride we have drugs b}- the aid of 

 which the parts are artificially frozen, and thus deprived of 

 sensation. Ether is applied with a spray, as first intro- 

 duced into human medical practice by the late Sir B. W. 

 Richardson, M.D. 



The parts to be anaesthetized should have the hair removed 

 by shaving, and be then rendered aseptic and as dry as 

 possible, the ether being forced out of the bottle by the 



