HOBSE-SHOEING. 137 



we pass to the consideration of the latter, as a whole, to allude to the 

 structure and uses of that narrow strip of horn, whose presence 

 every farrier or veterinary surgeon is cognizant of, but whose character 

 and functions have been strangely left out of consideration by all 

 anatomists hitherto. I refer to the "white line" or "zone," the 

 slender intermediate band that runs around the margin of the sole, 

 and connects that plate of horn so closely to the wall as to make 

 their union particularly solid and complete. When preparing the- 

 border of the hoof for the reception of the shoe, this part is easily 

 distinguished by its lighter color (in a dark hoof), and by its being. 

 softer and more elastic than either the sole or wall, between which it 

 is situated. It would appear to be secreted by the villi which ter- 

 minate the lower end of the vascular laminae, and the horny leaves of 

 the wall are also received into its substance — a circumstance that 

 renders the junction of the two more thorough. I think there can 

 be no doubt that the principal use of this elastic rim of horn, placed 

 in such a situation, is to obviate the danger of fracture to which the 

 inferior part of the hoof — particularly the sole — would be liable, if 

 the junction between the hard and comparatively inelastic sole and. 

 wall was directly affected without the interposition of such a body. 



It may be noted, that it is through this soft border of horn that 

 gravel and foreign matters usually find their way to the sensitive 

 parts of the foot, and there excite such an amount of irritation as to 

 lead to the formation of matter, and cause much pain and lameness — 

 an accident which the older farriers termed ''graveling." 



In viewing the horse's hoof as a whole, and in the unshod state, 

 we find that it presents several salient characteristics, the considera- 

 tion of which ought to dominate or serve as a guide in framing rules- 

 for the observance of farriers in the practice of their art. The first 



