560 Veterinary -Captain Frederick Smith [May 3, 



We may now reverse the experiment, and shoe the horse in such a 

 manner that what is left of the foot-pad is made to rest on the ground : 

 in a month, or even less, the most marked changes have occurred, the 

 pad commences to unfold itself like a bud, the cushion becomes larger, 

 the foot wider, and in three months the transformation may be 

 complete. Such is an experiment which may be performed on any 

 horse with absolutely identical results, and proves to demonstration 

 that the pad is intended by nature to rest on the ground. 



We must now take a cursory glance at the internal foot, as our 

 time will not admit of a complete examination. 



The bones found in the foot are three in number : two wholly 

 belong to the foot, one belongs partly to the foot and partly to the 

 portion of the limb above the hoof known as the coronet. Dealing 

 only with the foot bones, one is found to resemble a miniature hoof in 

 shape, is very porous in its structure, and has growing from each ex- 

 tremity a plate of cartilage which extends superiorly above the hoof 

 and posteriorly as far back as the heels. The bone is porous to 

 admit of the innumerable blood-vessels for which the sensitive foot 

 is remarkable, while the introduction of the plates of cartilage is to 

 allow of lateral movement in the posterior part of the foot, such as 

 would not be possible if bone existed in its place. 



The second bone of the foot is one ot the smallest, but practically 

 one of the most interesting in the body. Its position can be seen in 

 this model ; and it is unfortunately the seat of the most incurable 

 lameness to which the horse is liable. Beneath this small bone is a 

 tendon which flexes the feot and keeps the bone in position. 



Surrounding all these are the sensitive structures to which previous 

 reference has been made. But before passing on to the final subject for 

 our consideration, I must diaw your attention to the remarkable vas- 

 cularity of the foot ; in few parts of the body do we find so many 

 biood-vessels. These diagrams can give you but a faint notion of the 

 number of vessels in the foot, and even they deal only with the veins ; 

 to have introduced the aiteries would have complicated the drawing 

 too much. Practically the whole of the sensitive foot is scarlet in 

 colour, from the amount of blood it contains, and the sole use of this 

 bleod is to manufacture the horny covering. 



We alluded just now to two plates of cartilage found in the foot ; 

 they occupy the position shown in the diagram, and their use is 

 connected with the important lateral movement or expansion which 

 the foot undergoes when weight is placed on it. If it were not for 

 these elastic plates, expansion of the foot would be rendered very 

 difficult. The plates also assist the circulation of the blood in the foot, 

 by exercising, during their elastic movements, pressure on the veins, 

 and thus pumping the blood out of the part. 



Perhaps the greatest interest in the foot is centred in the 

 mechanisms which prevent concussion, these are as follows : lateral 

 expansion of the foot, descent of the vascular within the homy foot, 

 flattening of the sole, and sinking of the heels. 



