Accidents and Operations. 397 
The age of the animal, the enormous obesity, and weak 
condition of the heart precluded the administration of 
chloroform, and the usual method of reduction: so I had 
a suitable truss applied, which the patient continues to 
wear, 
FISTULA. 
Fistulz, or sinus wounds, occur in different positions, 
but are all, more or less, due to some local irritation, very 
often abscess, and present the same structural character, 
z.é2, a narrow constricted passage lined by thickened 
membrane, which secretes a variable unhealthy purulent 
discharge. 
Fistula in ano has already been described in Chapter Vv. 
A troublesome form of fistula is that affecting the 
‘achrymal apparatus (Féstula Lachrymalis), which most 
frequently originates in some persistent obstruction in the 
nasal or lachrymal duct. In 1886 I received a case of this 
description into my hospital. The external opening was 
about an inch and a half below the eye, through which the 
lachrymal secretion freely passed. The treatment consisted 
in astringent injections, and the application of nitrate of 
silver,—the process of healing occupied seven weeks. 
Sometimes it is necessary to slit up the canaliculus, and 
maintain for a period an open wound. 
Fistula Parietal Abdominalis may result from. an 
imbedded thorn or other punctured wounds, or abscess. 
Last year a Yorkshire terrier was brought to me for advice 
as to an old standing sore which the animal persistently 
licked. An examination revealed a fistulous wound in the 
abdominal parietes. The opening was opposite and about 
an inch to the left of the prepuce, the sinus running back- 
wards for some three inches, and obliquely towards the 
penis. The treatment consisted in a free incision of the 
sinus, carried backwards from the opening, and the sub- 
