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THE SHAPE OF THE WALL— DIFFICULT TO DESCRIBE. 



As to the question whether the general form of the foot be 

 cylindrical or cone-shaped, I agree with Spooner, that in, some 

 horses no doubt the feet are cylindrical ; but as in the great 

 majority of hoofs, and particularly those which we consider the 

 best, the circle at the upper part is less than one at an equal 

 distance lower down, we shall be more frequently correct if we 

 describe it as the " frustum of a cone, the base and summit 

 of which have been intersected by two oblique planes." The 

 fact, however, is, that no mathematical figure can correctly 

 describe the exact shape of the foot, for viewing it in front we 

 may pronounce it conical, whilst at the same time its lateral 

 aspect may be that of a cylinder. 



THE CORONARY CONCAVITY. 



On the inside of the upper margin of the wall is to be seen 

 a concavity, about three quarters of an inch in depth, and extend- 

 ing throughout the entire upper circumference of the wall. This 

 is named the Coronary Concavity, and by some the Coronary 

 Ring. This concavity is for the repose of the organ which secretes 

 the fibrous, and therefore the principal portion of the wall, and is 

 called the Coronary Secretary Substance. On the surface of 

 the Coronary Concavity may be seen, by the naked eye, a vast 

 number of minute perforations, which receive the secreting 

 villi of the Coronary substance. Quoting Haycock : " These are 

 the commencement of the horn tubes which are continued from 

 the top to the bottom of the hoof; the hoof, in part, is a series 

 of minute cylinders or hollow tubes. These tubes exist in im- 

 mense numbers, are placed side by side, and traverse the entire 

 length, or rather depth of the horny mass. The animal, strange 

 as the statement may appear, stands and travels upon thou- 

 sands of cylinders, all arranged with extreme regularity, and 

 held together by a common glutinous medium, in which is de- 

 posited the peculiar pigment giving color to the hoof." 



THENARS, BRACES, OR BUTTRESSES OF THE WALL. 



Another portion of the foot has received the names of Bars. 

 Spooner describes them as a continuation of the wall, being 



