156 GENERAL THERAPEUTICS FOR VETERINARIANS 



4. FIRING. CAUTERIZATION 



General. — Firing is one of the oldest methods of treatment and 

 specifically a veterinary remedy, which cannot be dispensed with 

 even to-day, despite the large number of similariy acting chemical 

 substances (caustics). It is, on the contrary, among the most valu- 

 able of surgical aids. As a rule, wrought cautery irons of various 

 forms (knife, hatchet, button, conical form, etc.) are used in firing, 

 in addition to which Paquelin's platinum cautery apparatus is 

 used in clinics and on small animals. There are several varieties 

 of firing: superficial (point and line firing), percutaneous, perforat- 

 ing (spavin firing) and subcutaneous. (See the text-books on 

 operative surgery.) 



Actions. — The effects of firing are very numerous: 



1. The immediate result is a local destruction of tissue. The 

 heat first coagulates the albumin, then follows the formation of an 

 eschar and carbonization. Associated with this action is the dis- 

 infecting and haemostatic effect of the hot iron. 



2. A hyperaemia and inflammatory reaction develops in the 

 region immediately surrounding the cauterized area. The circu- 

 lation of blood and resorption are stimulated in consequence. An 

 extensive outwandering of white blood-cells, local hj^erleucocy- 

 tosis, phagocytosis and histolysis occurs, similar to that which 

 follows the rubbing in of tincture of iodine (see p. 148). 



3. The pronounced irritation of the cutaneous nerves acts 

 reflexly upon the nervous system. Firing consequently operates 

 like a powerful cutaneous irritant (principle of cutaneous irritation 

 and counter irritation). 



4. The eschar which results from firing exerts, according to the 

 usual acceptation, a mechanical pressure upon the underlying 

 tissues and promotes, like massage, the resorption of the patho- 

 logical products (?). 



Uses. — 1. The most important indications for the employment 

 of the firing iron are the chronic inflammatory conditions of the 

 bones, joints, tendons and tendon sheaths : spavin, ring bone, ex- 

 ternal spavin (rehbein), curb, splints, chronic arthritis, tendinitis, 

 tendovaginitis and articular galls. While the firing iron should 



