190 CHAPTER 19. 



the fingers firmly but cautiously along the outside ; and the orifices 

 themselves must be frequently washed with warm water in order to 

 keep them clean and open. If these details are neglected, the channel 

 and orifices will soon become choked, and the pus will make exits for 

 itself by large irregular holes, and permanent blemishes will probably be 

 the result. In order to secure easy exit for the pus, it is desirable, if 

 the seton exceeds six inches in length, that an intermediate opening 

 should be made with the scissors. The tape should be renewed every 

 ten days, or it will become rotten and may break. It should be secured 

 at both ends by a light piece of stick about three quarters of an inch 

 long, or the two ends may be brought together and knotted. 



389. Punching. 



The old-fashioned operation known as Punching was effected by an 

 instrument closely resembling a saddler's punch, which was driven 

 through the skin and subcutaneous tissues and through the periosteum. 

 Into the hole so made corrosive sublimate or other caustic was in some 

 instances inserted. 



Some years ago punching was much recommended as a remedy for 

 spavin, splint, and other such exostoses, but its effects are apt to be 

 violent and uncertain. An undue amount of inflammation is frequently 

 excited, which is likely to aggravate rather than to lessen the predis- 

 position of the part to throw out ossific material, resulting in many 

 instances in a permanent stiff joint. The more familiar remedies of 

 blisters and setons are much safer and more successful. 



390. Firing. 



Firing, otherwise termed the actual cautery, is the most powerful and 

 rapid of all agents used to produce inflammation artificially. 



On account of its more energetic action it sometimes succeeds in pro- 

 ducing the desired effect, even after other remedies have failed. Firing 

 has also the great collateral advantage of compelling the owner to throw 

 his horse out of work for a considerable length of time. On the other 

 hand, it has some considerable disadvantages. If at all severe, it pro- 

 duces a permanent blemish. Again its effect, though exceedingly vio- 

 lent, is but temporary. Nature, as previously stated, is unable to sustain 

 any very violent action for any great length of time. In consequence it 

 generally becomes necessary after firing to apply a blister to keep up the 

 irritation, and thus afford nature the means and the time needed to com- 

 plete the process of cure. This is particularly apt to be the case in 

 injuries of tendons and other structures of low reparative power. 



We have stated above that only one degree of inflammation, namely, 

 that intermediate between the excessively violent and the torpid stage, 

 is suitable for the purposes of repair. The reader may therefore ask, 

 how does so violent an irritant as the actual cautery answer this end? 

 This apparent contradiction, however, admits of explanation. 



In sprains of ligaments and tendons and such like cases we do not, 



