430 OPEEATIONS ON THE DIGESTIVE APPARATUS. 



that the deeper the action of the caustic, the more successful the 

 operation is Hkely to be. It is said that nearly one ounce of the 

 acid is required for a tumor as large as a man's fist, and that the 

 friction should be continued from three to five minutes. The 

 duration of the friction and the quantity of the acid to be used 

 must, however, be guaged by the dimensions of the tumor, and 

 also with careful consideration of the thickness of the skin. Dayot, 

 to whom is due the positive and i^ractical introduction of this mode 

 of treatment, proposes to apply the acid in instalments, and recom- 

 mends that the apphcation be repeated once or twice an hour, 

 according to the thickness of the skin, .until the desired effect is 

 assured. The result of our own experience is a conviction that as 

 a rule only a single apphcation is necessary. Nitric cauterization 

 produces a yellow eschar, which ordinarily remains for a long time, 

 soft, supple, and unctuous to the touch, but the epidermis of which 

 is easily lacerated. In some cases the formation of the eschar is 

 followed by a large swelling of the cauterized parts and the sur- 

 rounding tissues. Sometimes it makes its appearance immediately 

 following the operation, but more commonly it appears at a later 

 period, gradually increasing during the first hours following the 

 cautery, although again, in other cases, this swelling is altogether 

 absent. The oedema is the direct effect of the action of the caustic 

 upon the subcutaneous cellular tissue, which becomes infiltrated ; 

 and in this condition apphes a uniform pressure in all directions 

 upon the peritoneal hernial sac, crowding back into the abdominal 

 cavity the displaced intestines and preventing their return by the 

 kind of retentive bandage which is formed by the engorgement 

 which takes place around the sac. 



In the days following, after reaching the maximum develojD- 

 ment, the oedema gradually diminishes by resorption, becoming 

 at the same time somewhat harder, the portions of cauterized skin 

 which is in its center meanwhile gradually drying, and becoming 

 transformed into a dry, hard plate. 



In place of the hernia there now remains a fibrous mass of new 

 formation, which gradually diminishes and is soon more or less 

 resorbed. In the meantime, while these phenomena are taking 

 place, the process of the separation of the eschar has begun and 

 progressed, and on the eighth day, on the boundary between the 

 dead and the living structures, a fissui'e shows itself, and minute 

 granulations appear. The sej)aration goes on slowly, from the 



