108 
WILLIAMSON BEYDEN. 
ground it is seen by tlie way the shoe is worn that the weight is 
thrown on the outside toe; this is evidently tc* save the inner 
quarter or heel, which, if brought in contact with the ground in 
progression would cause pain. If, therefore, one part of the foot 
—the base—is doing more than its share of work, or doing it 
disadvantageously, it is equally probable that parts of the super¬ 
structure—the limb—are also placed at a disadvantage. In a 
limb thrown out of balance in this way, the position of the bones 
is changed ; some of the muscles and tendons may shorten, while 
others relax. The metatarsal flexor, especially the tendinous 
portion and the ligaments, of whatever part of the hock is first 
affected at their insertions, are subjected to more than usual 
strain , sometimes accidentally violent perhaps, but in many 
cases an often-repeated or a continued gradual strain. In young 
limbs this may at first give rise to only a slight projection, or 
what might be called perhaps a physiological hypertrophy. 
When the irritation is kept up or some degree of inflammation, a 
greater area of the hock becomes involved and anchylosis 
more or less complete takes place according to the age of the 
animal, the richness or poverty of the tissues of the joints, the 
powers of resistance of the cartilages, and the demand made upon 
them. 
In pathological new-born formations there is usually more or 
less degeneration of the original tissues, especially of the cancel¬ 
lated structures of the interior of the metatarsal and cuneiforms, 
sometimes atrophy appreciable of the metatarsal either from 
the new formations being developed at the expense of the 
original or form irregular or diminished supply of nutritive and 
vital power. 
The spavin, therefore, is very seldom the only difficulty to be 
overcome or the cause of all the other changes. Consequently, if 
the conditions of the limb which predisposed it to spavin con¬ 
tinues to exist unnoticed, the application of remedies only to the 
hock is patchwork as empirical as it is unscientific. 
Discussion followed the reading of the paper: 
