376 DISEASES OF THE HORSE'S FOOT 



feet so much of the wall is isolated at the bottom that 

 insufficient is left to nail the shoe to. 



The next line to be made is the rear one. Its correct 

 position is ascertained by first noting the junction off the 

 wall with the bar (see groove 2, Fig. 149) ; and its inferior 

 end must be just anterior to the inflexion of the wall. This 

 is done that we may avoid cutting the bar. The position 

 oi the lower end of the rear line thus ascertained, it is run 

 upwards with the chalk in the direction of the horn fibres. 



13 2 



Fig. 148. — Diagram illustrating the position of the Grooves in 

 the Wall in Colonel Smith's Operation for Side-bone. 



i, 2, and 3, mark the grooves in the order in which they are made; 



the dotted line a marks the position taken by the anterior line 



Vher.the side-bone is one reaching far forward, while the dotted 



lines fr and c mark the position of the additional grooves to be 



made if thought necessarv. 



The third line is made in such a position as to divide 

 into two equal portions the wall between lines 1 and 2. 

 Here, however, some operators prefer to make two, or even 

 three, lines, adding those as at b and c, Fig. 148; and 

 Smith himself says that a multiplicity of lines is an advant- 

 age rather than not. 



In any case, having once determined the position of the 

 lines, they should be plainly marked out with chalk, and 

 then viewed from a distance with the foot on the ground, in 



