FAULTY CONFORMATION 123 



cooler and more humid atmosphere of winter. It is inter- 

 esting to note, too, that an alternation of humidity and dry- 

 ness is far more liable to injure the quality of the horn and 

 tend to its contraction than the long-continued effects of 

 dryness alone A common illustration of this is to be 

 found in the effects of the ordinary poultice. Everyone 

 knows that when, after a few days' application, they are 

 discontinued, we get as a result an abnormally dry and 

 brittle state of the horn. This is doubtless due to the 

 poultice removing this thin, varnish-like, and protective 

 pellicle known as the periople, and thereby allowing the 

 process of evaporation to act on the water normally con- 

 tained in the hoof. 



Exciting Causes of Contraction. — Among these, first place 

 must undoubtedly be given to shoeing. This does not 

 necessarily imply shoeing more than ordinarily faulty, nor 

 a faulty preparation of the foot, but shoeing as it is gener- 

 ally practised. No ordinary shoe, except a few devised for 

 the purpose, such as the Charlier or the tip, allows the frog 

 to come in contact with the ground. This we take to be 

 the main factor in the causation of contracted heels, espe- 

 cially with a predisposition already present in the foot it- 

 self. In the words of Lungwitz : ' Regarded from this 

 point of view, there is no greater evil than shoeing. It 

 abolishes the necessary counter-pressure, and thus inter- 

 feres with expansion. Bars, sole, and frog cannot perform 

 the functions that naturally belong to them as they would 

 do without the shoe.' 



In addition to the evil of the shoe itself, errors of prac- 

 tice in the forge contribute to the causation of contraction. 

 Taking first the preparation of the foot, we find that often 

 the heels are lowered far too much, and the toe allowed to 

 remain too long. This can have but one effect — that of 

 throwing a greater proportion of the animal's w r eight upon 

 the heels than properly they should bear, with, what we 

 now know to be the consequence of that, a corresponding 

 pushing inwards and downwards of the horn ; in other 

 words, contraction. 



