AS TO SOUNDNESS. 35 
extent, and consequences of which we have no means 
of estimating. I refer to the weakness following a severe 
blow upon a joint. 
Question a man who has suffered at any time from 
a severe blow upon one of his joints, and he will tell 
you that the joint is weak, and yet he may have no 
scar whatever to show you. Four years ago I received 
a blow from a horse on the knuckle of the index finger 
of my right-hand while bleeding him at the toe. At 
first I thought the joint was laid open, but this proved 
not to be the case. The only evidence left now is a 
cicatrix of the skin, which is freely movable, and can 
be pinched up as high:as the skin on the fellow knuckle ; 
the tendon over it is also freely movable, and so is the 
joint ; and yet, with all this seeming perfection, the joint 
is weak. This being so, then you see we have two forms 
of imperfection only to look for in the knee of the horse: 
namely, mechanical impediment: and weakness. The 
former arises out of either-of the fourth or fifth degrees 
of injury, which we have such a ready and sure means of 
detecting ; the latter we are not so certain about—the 
evidences of a blow sufficient to cause permanent weak- 
ness being more equivocal. But, practically, we look to 
evidences of injury to the hair; such as absence, stiff- 
ness, or discolouration ; finding any of these, unsoundness 
is our verdict, although the action may be perfect, and 
the horse in every other respect sound. This is such an 
important part of our present study, that I shall make a few 
more remarks upon it at the beginning of my next lecture. 
