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NAVICULAR DISEASE 



both chronic and recent, is the product of contraction, which 

 is associated with an ascended frog and wired in quarters. The 

 result is a loss of substance and functions in the frog-tissues, 

 and concussion to the bony constituents of the foot, whereby 

 other specific lesions of the tissues composing the joint are 

 directly or indirectly produced. 



RINGBONE 



is also the result of concussion, occasioned by the diminution 

 or destruction of the elastic properties of the foot, induced in 

 the first instance by contracted quarters, and a predisposing 

 conformation of the pastern joint. 



CORNS 



are the products of lateral pressure, which gradually converts 

 the naturally rounded inflection at the junction of bar and wall 

 into an angular one ; the vascular and nerve-filaments becom- 

 ing crushed between the sides of the angles near its point ; 

 pressure on the nerves producing the pain and lameness ; and 

 the rupture of the vessels causing extravasation of their con- 

 tents into the horny sole at this spot. 



QUARTER-CRACK 



is invariably the result of that inverted order of things, whereby 

 the quarters are contracted, which prevents their due expan- 

 sion, when weight is thrown upon the foot in motion ; and are 

 expanded where they ought rather to contract ; and hence the 

 hoof splits from internal lateral pressure exerted in the wrong 

 place. 



TOE-CRACK 



is caused by the tendency of the toe to expand, when and 

 where it ought not to, in consequence of its reciprocal rela- 

 tions to the heels and quarters. 



