248 PRINCIPLES OF VETERINARY SURGERY 



sists of forcing the tissues apart with weak solutions of 

 chemical analgesics. His solutions, consisting chiefly of 

 cocaine, morphine and sodium chloride were forced in con- 

 siderable quantities between the two layers of the skin or 

 between the subjacent tissue layers. The claim was made 

 that parting the anatomical elements of the tissues had in 

 itself a marked anaesthetic efifect, but later developments . 

 have shown that the good results were due more to the 

 action of the chemical analgesics than to the separation of 

 the tissues, and hence the method, as such, became obso- 

 lete. 



Cocaine was the first chemical anaesthetic to attract at- 

 tention and it has held its place at the head of the list until 

 the present, day in spite of the frequent introduction of 

 other substances claimed to possess equal anaesthetic action 

 and less toxicity. 



In veterinary surgery .local anaesthesia did not come into 

 general use until the late 90's, although there is some evi- 

 dence that it was used here and there by some veterinar- 

 ians as early as 1888. During the last few years it has 

 come into very general use wherever scientific veterinary 

 surgery is practiced. Today it has numerous indications 

 for which it is used effectually. By its judicious use certain 

 operations otherwise requiring recumbent restraint are per- 

 formed with perfect precision in the standing position with- 

 ou:t the least discomfort to the patient. It has come into 

 quite general use for very painful operations that are rather 

 too brief to warrant, the. administration of a general anaes- 

 thetic. In surgery of the eye it has become indispensable. 

 In the diagnosis of lameness it is invaluable. The lameness 

 of unknown origin is located by the cocainization of the 

 nerve trunk supplying the sensory innervation of the sus- 

 pected region. The great value of local anaesthesia in these 

 several connections is no longer questioned, in spite of the 



