112 SHOEING. 



has weakened the strength of the quarters. Nature has, however, set 

 the example, by weakening the horn at the quarters ; nevertheless, by so 

 doing she has not destroyed the strength of the hoof. The quarters of 

 an old shoe, when removed after six weeks' hard wear, invariably are 

 not sensibly duninished in substance, showing that the lessened amount 

 of horn communicates small friction to the metal. Besides, the toe is 

 supported upon massive iron, while the heels are upheld by blocks of the 

 same metal. A law of mechanics instructs us that if the extremities of 

 any powerful substance are adequately sustained, the body which bridges 

 over the space may be without support. The heels being raised to an 

 equal height with the toe, the metal left at the quarters, as it is removed 

 from attrition, is imagined to be fully equal to the necessities of its posi- 

 tion. 



A HEAVY SHOE. 



A LIGHT SHOE. — SHOWING THE MANNER IN WHICH CALKINS MAY BE FORMED, WITHOUT ANT 

 INCREASE OF WEIGHT. 



The diagram exhibits the Slipper Shoe, as suited for different breeds of animals ; also shows the 

 sameness in both kinds of manufacture. 



Most existing shoes are fullered, or have a hollow space, narrow but 

 long, near to the outer margin. Into this empty void or groove the 

 heads of the nails are received ; but as the substance in front is ground 

 down by wear, of course the duration of the shoe must be shortened in 

 proportion to the depth of the fullering. That the reader may fully com- 

 prehend the signification of a fullered shoe, on the following page is a 

 copy, made from Mr. Goodwin's excellent work on Shoeing, which the 

 author can recommend as the fullest, the most explicit, and altogether the 

 best book on this topic which was ever written in the English language. 



By inspecting the next illustration, which represents the ground sur- 

 face, the reader will perceive an indented void near to the outer margin. 



