ARTIFICIAL INFLAMMATION. 191 



and cannot apply the actual cautery to the seat of the disease, but only 

 to a neighbouring part. We produce violent irritation in the outer skin, 

 but the injured part partakes only in a modified degree of the excite- 

 ment set up in its neighbourhood. Firing is simply the means by which 

 sufficient amount of active inflammation is set up in the injured part to 

 enable nature to complete the process of repair. 



An opinion however is prevalent, that much of the benefit of firing in 

 cases of sprains of ligaments and tendons arises from its producing con- 

 traction of the skin, and thereby forming a permanent bandage round 

 the injured part. There are great reasons, however, to doubt whether 

 any such permanent contraction of the skin takes place. The vitality of 

 the skin is not destroyed by firing, and living skin is, we know, highly 

 elastic. If the vitality were destroyed by the operation, the dead part 

 would by the ordinary processes of nature be cast off, for no union can 

 exist between a dead and living portion of the body. It is argued, how- 

 ever, that though the vitality of the skin is not destroyed altogether, 

 yet the new skin, which replaces that injured by the firing iron, is not 

 true elastic skin, but a hard fibrous semi-tendinous material incapable of 

 expansion, useful indeed in uniting the edges of the skin, which has been 

 cut through in many places, but differing widely from the original tissue. 



Admitting this to be true, we still think that there is an amount of 

 elasticity in the portions of the skin not destroyed by the firing which 

 must prevent its acting as a permanent bandage. 



Again the leg, for a long time after the wounds in the skin caused by 

 the operation have completely healed, remains larger than usual. 



Now if the vitality of the skin were really destroyed by the firing, the 

 skin would not contract on the leg, as it gradually became finer; and 

 therefore, far from acting as a permanent bandage, it would fit rather 

 loosely round it. We must therefore repeat our belief, that the benefit 

 derived from firing arises simply from its action as an irritant, promising 

 a more than usually lasting effect. Of all notions connected with firing 

 the most absurd is the idea that it may be useful as a preventive against 

 future lameness. There are people who fire, or, as they term it, " just 

 touch with the irons," the inside of the hocks of all their young horses 

 to prevent their having spavins, and also the posterior part of the hocks 

 to prevent their having curbs. What benefit they expect to derive from 

 thus artificially exciting irritation and inflammation in a sound hock, it 

 is hard to say. 



Others, with scarcely more reason, fire the hock after curb or spavin 

 has completely formed, although no lameness is caused. There is no 

 sense in this. Curb, though it generally produces lameness during the 

 process of its formation, rarely does so after the parts have consolidated. 

 Again, if a spavin, when completely formed and consolidated, is so placed 

 that it does not interfere with the movements of the joint, the proba- 

 bility is that it will never cause lameness. 



Frequently the results occurring from the application of the actual 

 cautery are of a serious character. The shock produced by the violence 



