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the crack at the toe. Judicious mechanical expansion of the 

 quarters will close a toe-crack, as well as a quarter-crack, in 

 the most effective manner, no fissure made by knife or firing- 

 iron being necessary to prevent the extension of the crack. 

 In this case " the cause being removed, the effect ceases." 



A SINE QUA NON. 



The application of the shoe in Quarter-crack is precisely the 

 same as. in Simple Contraction, but there is a difference in the 

 preparation of the foot. The bar and posterior sole should be 

 cut down upon freely, and the heel, on whichever side the 

 crack exists, should be opened in order to allow the affected 

 quarter to open out well under the pressure of the dilator. It 

 is also a sine qua ?ion that a nail should be got in posterior to the 

 crack, and if the crack extends from the top to the bottom of 

 the quarter, one nail-hole should be punched so as to admit of 

 a nail passing through the wall transversely to the line of the 

 fracture. 



AN EXPLODED FALLACY. 



The inner quarter is the most subject to fracture as it is 

 always the thinnest and weakest portion of the whole wall, and 

 therefore the first generally to contract upon its lower, and to 

 yield to the lateral pressure upon its upper margin. Some 

 attribute the extra liability of the inner quarter to fracture, to 

 the fact that its position is nearer or more under the centre of 

 gravity than the outer. The analysis of the causes I have 

 given, leaves this hypothesis out in the cold. I have no use 

 for it in this place. It has done duty for a learned reason long 

 enough, and has been relegated by me long since to the limbo 

 of exploded fallacies. The causes can be fully demonstrated, 

 and what is of still greater consequence, easily removed, with- 

 out its, to me, questionable influence. 



I have some respect for the teachings of nature in anatom- 

 ical construction, and for myself am satisfied that if nature had 

 designed the inner quarter to sustain more weight than the outer, 

 she would have made the inner quarter the stronger instead of 



