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denser than that of other parts. ‘The density of the fibres of which the horn 
is composed, is noticed to become greater as they approach the surface of 
the wall, the outer layers acting as an efficient protector for the inner 
structures of the foot. The frog is a triangular horn of a very elastic, fine, 
tough texture, more pliable than the sole. At its front end or apex, it is 
seen to consist of a single ridge, but behind it is cleft to allow of motion in 
the posterior part of the hoof. 
The structures of the foot are abundantly supplied with blood vessels 
and nerve filaments, and owing to their encasement in a horny covering, the 
foot is generally the seat of acute pain when inflamed or injured. 
LAMINITIS, AND PUMICED FOOT. 
THERE are two distinct diseases affecting the feet of the horse which 
cause heat, pain, and lameness. The first of these is termed laminitis, and 
the second navicular disease. The one may lead to a convex condition of 
the sole, commonly spoken of as a pumiced foot, while the other leads to 
contraction of the foot. It will be our endeavour in treating of these 
diseases to clearly demonstrate the difference between these two affections, 
not only because they are so constantly confounded, but also because they 
both assume such a variety of forms, 
The terms “founder,” “chest founder,” “fever in the feet,” “fourbure,” 
and “‘laminitis,” are all names for the same disease. The two former terms 
appear to have arisen from the fact that the horse suffering from fever in the 
feet, seems to founder or stumble in his gait. Laminitis, or inflammation.of 
the sensitive or vascular structures of the foot may be acute, subacute, or 
chronic, In fact, it may be seen in all forms, from that manifested by a slow 
pottering gait, accompanied by no constitutional disturbance, to an acute 
inflammatory disease, accompanied by high fever, acute pain, accelerated 
pulse, and high temperature. As a rule, the fore feet are attacked, but not 
uncommonly the hind ones are also implicated. We agree with Percivall 
in maintaining that the foot most subject to laminitis is the broad flat one, 
and that the horses most commonly affected are half-breds and cart-horses. 
On many occasions however, acute laminitis does attack hunters and 
thoroughbreds. 
Acute laminitis, of all diseases to which the horse is subject, probably 
causes the most intense agony. The symptoms of this malady are very 
characteristic. In cases where both fore feet are affected, the 
action is slow, and the animal seems stiffened, and is often described by the 
attendants as “ fast in the chest.” The feet are placed slowly and gingerly 
to the ground, with the heels first, and the patient “blows hard” as a result 
of the high fever and great pain. The distressed animal unwittingly makes 
an effort to move forwards by placing his hind legs as far under his body as 
possible; he then raises both fore feet, and, as Percivall says, makes a 
“timid leap forward.” In other cases he will gingerly advance first one leg 
‘and then the other ; and again at other times he will rest in the recumbent 
