OSSIFICATION OF THE CARTILAGES, &c. 321 



produce injury in another form. Grease has occasionally followed canker. They have 

 been known to alternate. It may, therefore, bt prudent, when the cure of a cankered 

 foot is nearly effected, to subject the horse to a course of alteratives or diuretics. 



OSSIFICATION OF THE CARTILAGES 



Mention has been made of the side cartilages of the foot, occupying (see cut, page 

 276) a considerable portion of the external side and back part of the foot. They are 

 designed to preserve the expansion of the upper part of the foot, and especially when 

 that of the lower part is limited or destroyed by careless shoeing. These cartilages 

 are subject to inflammation, and the result of that inflammation is, that the cartilages 

 aie absorbed, and bone substituted in their stead. This ossification of the cartilages 

 frequently accompanies ringbone, but it may exist without any affection of the pastern 

 joint. It is oftenest found in horses of heavy draught. It arises not so much from 

 concussion, as from sprain, for the pace of the horse is slow. The cause, indeed, is 

 not well understood ; but of the effect, there are too numerous instances. Very few 

 heavy draught-horses arrive at old age without this change of structure; and particu- 

 larly if they are much employed in the paved streets. The change commences some- 

 times at the anterior part of the cartilage, but much oftener at the posterior and inferioi 

 part. " From the combined operation of great weight and high action, the feet, and 

 particularly the heels, come with great force on the ground. The cartilages, being 

 embedded in the heels of the feet, are, therefore, the parts that receive the greates 

 degme of concussion, the consequence of which is, that subacute inflammation is se 

 up, and the secreting vessels deposit ossific instead of cartilaginous matter, in thi 

 room of that which is absorbed in the usual process of nature."* 



No evident inflammation of the foot, or great, or perhaps even perceptible lame- 

 ness, accompanies this change ; a mere slight degree of stiffness may have been ob- 

 served, which, in a horse of more rapid pace, would have been lameness. Even 

 \vlien the change is completed, there is not in many cases anything more than a slight 

 increase of stiffness, little or not at all interfering with the usefulness of the horse, 

 When this altered structure appears in the lighter horse, the lameness is more deci- 

 ded, and means should be taken to arrest the progress of the change. These are 

 blisters or firing; but, after the parts have become bony, no operation will restore the 

 cartilage. Some benefit, however, will be derived from the use of leather soles, 

 Advantage has resulted from bar-shoes in conjunction with leather. 



Connected with ringbone the lameness may be very great. This has been spoker 

 Df in page 277. 



WEAKNESS OF THE FOOT. 



This is more accurately a bad formation, than a disease ; often, indeed, the result 

 of disease, but in many instances the natural construction of the foot. The term 

 weak foot is familiar to every horseman, and the consequence is too severely felt by 

 all who have to do with horses. In the slanting of the crust from the coronet to the 

 toe, a less angle is almost invariably formed, amounting probably to not more than 

 forty instead of forty-five degrees; and, after the horse has been worked for one 01 

 two years the line is not straight, but a little indented or hollow, midway between 

 the coronet and the toe. This has been described as the accompaniment of pumiced 

 feet, but it is often seen in weak feet, that, although they might become pumiced by 

 severity of work, do not otherwise have the sole convex. The crust is not only less 

 oblique than it ought to be, but it has not the smooth, even appearance of the good 

 "oot. The surface is sometimes irregularly roughened, but it is much oftener rough- 

 ned in circles or rings. The form of the crust likewise presents too much the 

 appearance of a cone ; the bottom of the foot is unnaturally wide in proportion to 

 the coronet; and the whole of the foot is generally, but not always, larger than it 

 should be. 



When the foot h lifted, it will often present a round and circular appearance, with 

 a fullness of frog, that would mislead the inexperienced, and indeed be considered 

 as almost the perfection of structure ; but, being examined more closely, many glar 

 ing defects will be seen. The sole is flat, and the smith finds that it will bear littl* 

 vi no paring. The bars are small in size. They are not cut away by the smith, bol 



* W. C. Soooner on the Foot of the Horse, page 249. 



