542 
LAMENESS TN HORSES. 
QUARTER SANDCRACK. 
The Situation of this Crack is the slanting line of 
the wall of the hoof, directly opposed to the extremity of the 
ala of the coffin bone ; and it is oftener found in the inner than 
in the outer quarter. Added to which, the hoof in which such 
crack occurs is always a contracted one : quarter sandcrack, no 
more than toe sandcrack, never happening in a hoof disposed to 
obliquity and flatness. The same description of horse and foot 
which is predisposed to contraction is for the same reasons pre- 
disposed to sandcrack. There is an obvious connexion between 
contraction and quarter sandcrack. The light, near-the-ground 
stepping horse, with strong, narrow, upright hoofs, will be equally 
likely, under certain conditions, to have the heels of his fore 
hoofs becoming contracted, and exhibiting quarter sandcracks. 
Hot stables conduce to this; but more still hot climates. 
Hurtrel D’Arboval informs us, that at the time the French army 
was in Egypt their horses were continually having sandcracks ; 
and he adds, that long voyages on board of ship are on occasions 
attended with like results. 
The proximate Cause of Quarter Sandcrack is, 
then, contraction. The horn, from dryness or other cause 
rendered cracky and fragile, breaks at the quarter of the wall, 
from being at that part bent across the edge of the ala of the 
coffin bone, during the curving in of the heel, the result of con- 
traction ; and this oftenest happens to the inner quarter, from 
its being the thinner and weaker one, as well as from being the 
one which is the first and most disposed to contract. Not that 
sandcrack is the necessary consequence of contraction ; but that 
contraction becomes a necessary precursor to sandcrack. If this 
were not the explanation of the case, sandcrack would be 
as likely to occur in any part of the wall as at the quarter, 
and on the outer as often as on the inner side of the wall. This 
likewise accounts for the comparative infrequency of quarter 
sandcrack at the present day among our nag and cavalry 
horses, since that which has tended to diminish the frequency 
of contraction has had the same effect in regard to the occurrence 
of sandcrack. Greater attention to shoeing, and increased care 
about the condition of the hoof itself, has no doubt had very 
beneficial effect in the prevention both of contraction and sand- 
crack. 
The Origin of Sandcrack is usually sudden, both 
in the fore and hind feet ; though in the former case, from its 
situation in the inner quarter, a part not exposed to transient 
view, it is possible for a crack to exist for some time, unless 
