120 VETERINARY SURGICAL THERAPEUTICS, 
slow process of the phenomena of the existing osteitis and to the accu- 
mulation of food and saliva in the alveolar cavity. Some cesophageal 
fistule are obstinate and require surgical interference. As to the recto- 
vaginal and the vesico-vaginal fistule, attempts so far made with animals 
to bring about cicatrization have only proved unsuccessful. 
There are fistula of excretory canals which naturally have a ten- 
dency towards cicatrization: those of the perineum after urethrotomy, 
for instance. But almost all of them require a special treatment. 
There are three principal methods to be used: 1. Restore the normal 
course of the flow; 2. Create an artificial one; 3. Dry its source. 
If the fistula is recent, one may resort to the first method ; applica- 
tion on the fistulous orifice of a closing bandage, vesicating frictions, 
light and repeated cauterization of its edges, dilatation of the canal by 
injections or by repeated uses of the sounds and the like. Occlusion, 
vesication, and suture have often been used for recent salivary or urethral 
fistula. The second method is applicable only to a small number of 
cases ; it is especially advised for a fistula of steno duct, open on the 
cheek, To make a new way and dry the cutaneous fistula, the deep 
layers of the cheek, including the buccal membrane, are perforated on 
a level with the wound, which is then closed by suture or a pitch plaster ; 
the saliva escapes then into the mouth and transforms the newly-made 
tract into a fistula. Success is still more certain if the new tract is. 
drained while the old one is obliterated. The last method brings on 
recovery in cases of fistula by producing the atrophy of the gland. For 
certain salivary fistulz, irritating injections made in the parotid gland 
and the ligature of the excretory duct have been successfully employed. 
Purulent, stercoral, and vesical fistulae are quickly followed by 
erythema of the parts soiled by the substances escaping from them. 
In their neighborhood, the skin ought to be washed several times a 
day with a weak, tepid, antiseptic solution, and covered with boricated. 
vaseline or glycerine. 
For some subjects, it may be useful to institute an appropriate general 
treatment. Good food and tonics are always advantageous for debilitated. 
animals, weakened by an abundant suppuration of long standing. 
For certain fistula of the dog, an internal medication is advised (Fowler 
solution, Cod Liver Oil). 
VI. 
FOREIGN BODIES. 
Among the foreign bodies to be found in animals, some are formed 
in the organism under the influence of morbid processes (splinters, 
sequestra, calculi, pedunculated tumors of the peritoneum), but most 
of them have come from outside, having penetrated the organism either- 
