DISEASES OF THE LATERAL CARTILAGES 345 
however, much of what can really be urged against it dis- 
appears, and on farms and other places where a skilled and 
competent dressing of an operation wound cannot be looked 
for, it is sometimes wise to advise this method of treatment 
in preference to more advanced methods of operating. So 
far as we can judge, the after-effects are very little worse 
than those following other operative measures, more 
especially when a suitable case has been chosen. 
This method of treatment is particularly applicable to 
cases of chronic sub-horny quittor in the more posterior 
parts of the foot. Here, if one or more fistulas exist, their 
openings are probed and the direction of the sinuses deter- 
mined. In all probability they are burrowing down along- 
side the wall to the sole, where, for want of outlet, they are 
invading the substance of the plantar cushion or the plantar 
aponeurosis. 
Should this preliminary probing demonstrate that neither 
of the fistulas run dangerously near the joint, then the 
operation may be decided on. 
The animal is cast and chloroformed, the foot firmly 
fixed, and the horn of the quarter rasped away quite thin. 
The sole of the same side is also pared with the knife until 
the horn of both the quarter and the sole yields easily to 
pressure of the thumb. All that is then needed is three cr 
four long, round, and pointed irons (about } to 3 inch in 
diameter) heated to redness. These are inserted into the 
fistulas, and the false mucous coat of these passages thus 
destroyed. When the iron, on being directed into the 
fistulous opening at the coronet, is found to travel alongside 
the wall, and to easily reach the sole, it should be made to 
go further still. The sole is penetrated, and a dependent 
opening thus made for the escape of the discharge that 
afterwards accumulates. 
What happens now, of course, is that an intense and 
acute inflammation is set up along the whole track of the 
fistula, in which position the inflammatory changes were 
heretofore chronic. The whole lining of the fistula, and 
with it, we hope, all necrotic tissue, is cast as a slough, 
