ii8 



between the bars, and consists, not of solid horn, but of a 

 series of elastic arches ; the base of the frog lies between 

 and connects the posterior curved portions of the hoof, and 

 limits to some extent their action. 



The elasticity of the step of the horse is the result of a 

 most harmonious and complicated arrangement, namely, 

 the elasticity of — 



The sensitive laminae, 



The sensitive sole, 



The horny w^all. 



The arch of the sole, and 



The triple spring, 

 formed by the foldings of the frog and the manner of its 

 union with the bars. 



The internal parts of the hoof (or horny box) are the 

 coffin bone, the navicular bone, the fatty frog (or plantain 

 cushion), beside other tissues yet to be mentioned. 



Immediately joining and below the short or lower pastern 

 (os coronae, which is nearly square in form) is the coffin 

 bone (os pedes). This bone has a body and wings, and to 

 these wings are attached the lateral cartilages of the hoof 

 which are seen on the outside and form part of the heels. 

 It is light and spongy in texture, perforated with numerous 

 canals, through which numerous blood-vessels and nerves 

 are abundantly distributed to the highly vascular tissues 

 that surround it on all sides. Behind the coffin bone, and 

 lying in its concavity, is a small bone of peculiar shape called 

 the navicular bone. 



We have merely named and glanced at the anatomy of 

 the horse's foot; a complete scientific work on this subject 

 would require a large volume itself. Our object in this little 

 work is not so much the structure as the functions of those 

 parts which are constantly the seat of disease, and come 

 under our observation every day in diseases of the feet. 

 The parts we have already described are only horny or bony 

 tissues, which, except in cases of fracture, are seldom the 

 seat of disease. 



