PLANTAR SYSTFilM. 423 



until they reach the centre of tlie bottom of the foot, where they 

 terminate : these inflections or processes of the wall constitute 

 the bars. Altogether, the wall may be said to form about two 

 thirds of the entire hoof. 



Connexion. — Superiorly, around the coronet, the wall is united 

 with the skin ; inferiorly, within its circumferent border, with the 

 sole ; posteriorly, between its heels, with the heels of the frog ; in- 

 feriorly, between the bars, with the sides of the frog ; and 

 internally, with the sensitive laminse. Let us now consider the 

 wall in its detached or separate state. 



Figure. — That of a hollow cylinder, having the side presented 

 to the ground cut much aslant, and whose circle exhibits a hiatus 

 or deficiency behind, from the lateral boundaries of which issue 

 two narrow processes or appendages. Taking a lateral view, the 

 wall assumes a conical shape, being broad and deep in front, and 

 gradually narrowing as it stretches backward. 



Division. — For facility of reference, and in aid of our descrip- 

 tions, we distinguish in the wall, First, the toe ; secondly, the 

 quarters ; thirdly, the heels ; fourthly, the superior or coronary 

 border ; fifthly, the inferior or solar border; sixthly, the lamina 

 or lamella ; lastly, the bars or appendages. 



THE TOE forms the bow or front of the hoof, and compre- 

 hends about two-thirds of the superficies of the wall. It is the 

 deepest, broadest, and thickest part of the wall ; for reasons that 

 will appear hereafter. It exhibits a degree of slant about equal, 

 naturally, to an angle of forty-five degrees ; though there are varia- 

 tions from this which (as was explained before) will he found, in 

 a measure, to be dependent upon the oblique truncation of the 

 cylinder. When we come to understand the physiology of this 

 part, however, a more operative and efiicient cause for this varia- 

 tion will be found in the weight the wall has to sustain, and in 

 its own mechanical strength or force of resistance : on which 

 principle it is that light horses, thorough-breds, and poneys, as 

 well as mules and asses, have upright or strong feet (i. e.) walls 

 but moderately sloped ; whereas heavy horses, cart-horses, and 

 coach-horses, have commonly /fa^ or weak feet (i. e.), walls that 

 slant immoderately. And (as was before observed) upon the 

 degree of obliquity of the wall must very much depend that of 

 the pasterns. In estimating the slant or slope of the wall, it 

 is proper to distinguish between that which is consequent on the 

 detruncation of the hoof, and such as is the effect of a burthen 

 under which the wall succumbs. The depth of horn in front 

 of the toe, measuring from the termination of the skin to the 

 most prominent point below (and supposing the hoof to be cut 

 and ready to receive the shoe), may be rated at about three and 



