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bone and the tendon, and then attacks the tendon itself. At length, as the 

 disease progresses, these structures become welded together, and weakened 

 by the products of inflammatoiy action. 



The accon-ipanying picture is engraved from a photograph of the lower surface of a 

 diseased navicular bone, one-eighth enlarged. It shows the caries of the bone. 



The picture below (Sewell) represents a section of the horse's foot, 

 showing (A) the navicular bone, (B) the flexor tendon, and (C) the coffin 

 bone. It will be noticed that the navicular bone forms a kind of pulley 

 round which the tendon works. We shall have occasion to refer to this 

 picture again, as showing the method of treating navicular disease by the 

 operation of frog-setoning. 



