356 DADD’S VETERINARY MEDICINE AND SURGERY. 
terminates in exostosis, coated with some tissue very imperfectly 
representing the original laminated structure. 
Mr. Braby, the intelligent veterinary surgeon to Messrs. Bar- 
clay and Perkins’ establishment, to whom I am indebted for much 
of the information I possess on this part of my subject, has had 
niany cases of this description, one of which, of extraordinary char 
acter, I shall relate here. One of his dray horzes had suffered long 
and severely from toe sand-crack in one hind foot, but, at length, 
had recovered, and returned to work. Some time afterward, how- 
ever, during the season of influenza, he was attacked with a vio- 
lent laryngitis, which increased to a degree to call for the operation 
of tracheotomy, to save him from suffocation. Notwithstanding 
this temporary salvation, however, the patient, in the end, suc- 
cumbed to the disease. His post-mortem examination became 
doubly attractive, owing to the circumstance of the long-standing 
and obstinate sand-crack he had suffered from heretofore, and the 
result in this latter respect proved extremely interesting. The 
coffin bone, along its front, occupying the line of the surface be- 
tween the coronal process and the toe, exhibited a channel or losa 
of substance half an inch in breadth, and fully the same in depth, 
thereby robbing it of a quarter of an inch of its solid diameter. 
This, of course, left the bone considerably weakened, the result of 
which subsequently was, transverse fracture in two places, the 
fractures commencing upon the articulatory surface, whence they 
extended directly crosswise through the middle of its body, so as 
to become apparent upon its concave surface underneath. In 
addition to this, growing from the laminated interior of the wall 
of the hoof, opposite to the middle or deepest part of the channel 
in the coffin bone, was a projection of hard, horny, callous su’> 
stance, having a covering of imperfectly-formed horny lamin:e. 
At the time this horse was suffering in the greatest degree from 
this extraordinary product of sand-crack, constitutional irritation 
ran so high as even to create alarm for the animal’s life. The 
treatment of sand-crack, whether it be in the quarter or in the toe, 
will have to be conducted upon principles applicable to both form: 
of the disease, though one must be regarded as of much more con- 
sequence than the other. The treatment of quarter sand-crack, 
generally speaking, is but comparatively a simple affair ; indeed, 
so lightly is it looked upon by horsemen in general, that we should 
mp some risk of their displeasure, and our own reputation as 
