DISEASES FROM FAULTY CONFORMATION 171 
means the crack prevented from becoming longer. Very 
often this is all that is necessary. In fact, we may say 
here that, no matter what other treatment is adopted, the 
simultaneous application of a blister to the coronet is 
always beneficial. To derive full advantages therefrom, 
the blistering should be repeated several times at intervals 
of about a fortnight. 
(b) Clamping the Crack.—When the services of a skilled 
smith are at hand, one of the readiest methods of perform- 
ing this is to draw the edges of the crack together with an 
ordinary horse-nail. 
On each side of the crack a small horizontal furrow is 
burned or cut into the wall, leaving the horn for about 
¢ inch on each side of the crack intact. This provides a 
groove for the ends of the clamping-nail to rest in, and 
brings them flush with the outer surface of the wall. The 
nail is then driven carefully home through the crack, and 
WO TT 
Fic. 86.—THE SanpD-cRACK FIRING-IRON. 
the pointed end grasped by the farrier’s pincers. The edges 
of the crack are then drawn tightly together, and the nail 
firmly clenched. 
‘The horse-nails are prepared in the ordinary way as for 
driving, with the exception that each is pointed on the 
reverse side, to prevent puncturing the sensitive structures. 
Before being used the nails are put in a vice, and the head 
hammered to form a shoulder, to prevent their being driven 
too far into the wall, and breaking out the hold.’* 
Before driving the nail some operators burn or bore a 
hole for it. Opinion seems to differ as to whether this 
is at all necessary. 
A method of clamping which, on account of its simplicity, 
has become greatly popular, is that of Vachette. For this 
operation is needed the outfit depicted in Figs. 86 and 87. 
* Veterinarian, vol.-xlviii., p. 100. 
