CHAPTER III. 



ANESTHESIA. 



Anaesthesia may be divided according to its nature and extent 

 into general and local. We shall consider these in order. 



The first operation under ether was performed on the 14th October, 

 1846, by Warren, in the Faculty of Medicine at Boston. Boots and 

 Lister first employed ether in England. During 1847 several veterinary 

 surgeons published experiments showing the advantages of its use 

 in operations on the horse. 



Notwithstanding certain drawbacks ether was at first exclusively 

 used, but on the loth November, 1847, Simpson drew attention to the 

 anaesthetic qualities of chloroform, which he declared superior to its 

 predecessor. Chloroform soon displaced ether, maintaining its supre- 

 macy in man until a relatively recent date. In animals, save perhaps 

 the dog and cat, it is still the anaesthetic par excellence. 



Other substances have been introduced during recent years. The 

 first departure was probably the mixture of ether and chloroform, with 

 or without alcohol. The rectal administration of ether was then 

 suggested, followed by the use of morphine, the intra-venous, intra- 

 rectal, or intra-peritoneal injection of chloral, the inhalation of 

 chloroform in association with subcutaneous injections of morphine and 

 atropine, and the administration of benzine, paraldehyde, urethane, 

 hypnone, methylene, and amylene. When, as in oxen, the fliesh would 

 be used for human food in case of the operation failing, large doses 

 of alcohol are often given. 



In general anaesthesia the patient is thrown into a more or less 

 profound artificial sleep. It is not al\va3's necessary, however, to act 

 on the entire individual. Sometimes the operation only affects a very 

 limited area, and local anaesthesia suffices. Local anaesthesia is 

 generally produced by the application of ice or freezing mixtures, by 



