354 DADD'S VETERINARY MEDICINE AND SURGERY, 
the tu. aness of the hoof, and produces lesion of the sensitive parts 
underneath the horn, giving rise to some little hemorrhage ‘n the 
first instance, and subsequently to more or less inflammation— 
occasionally, even to suppuration, depending, of course, on the 
extent and nature and duration of the lesion, as well as on any 
treatment, or aggravation from non-treatment, it may have re- 
ceived since being occasioned. When the crack does not extend 
through the substance of the wall—which it sometimes dves not 
at first, though it may do so afterward—it may be said to be non- 
penetrant; and this, when it happens, seems to be referable te 
a sort of natural fusion there certainly exists between the solid 
horn, as it descends from its secreting gland, (the coronet,) and 
the horny lamine (new matter), which become glued to it in its 
course downward. It is in this uniting horny medium that seedy 
toe commences and progresses. 
Lameness is the usual accompaniment of penetrant sand-crack, 
but not the invariable one. When penetrant it is said to arise 
from the sensitive lamine getting pinched between the sides of 
the crack. However this may be, inflammation following the 
lesion has certainly its share in causing pain during action. In 
general, the lameness does not amount to much, nor is it of long 
duration, provided the sand-crack receive proper and timely at- 
tention ; but if the crack is not heeded, action of the foot will much 
aggravate the malady, and end in lameness increased so much as 
to forbid further use being made of the animal. 
ToE SAND-CRACK. 
Occurring in the hind foot, as this crack almost invariably 
does, occupying a different situation in the hoof, and arising alto- 
gether from a different cause, toe sand-crack may be regarded as 
almost a distinct affection. 
The subject of it is not the light horse, but the heavy one --the 
cart and wagon-horse, the dray-horse, the latter especially ; and 
in particular, I believe, in paved cities, they are the sufferers from 
this disease. I say ‘ suiferers,’ because it is only those veterinary 
surgeons whose practice lies among horses of this description that 
have any conception of the amount of pain and irritation with 
which sand-crack—simple as it may seem to those who are in the 
habit of y-eeting quarter crack only—is found to be accon + anied. 
