16 THE CANADIAN HOESB 



gLmblet, or the pointed red-hot iron, in these cases, are gone, 

 we hope, for ever. 



BING-BONE. 



Eing-bone is another very common form of exostosis 

 occurring to a ruinous extent in the lower breeds of horses 

 in Canada. 



It consists of a ring of bone, deposited around the head of 

 the small pastern-bone, or the lower end of the large one. 

 This, properly speaking, is ring-bone ; but the term is ap- 

 plied to all osseous deposits around this joint, no matter 

 whether in the form of a ring or not. It is seen on both the 

 hind and the fore limbs. 



Causes. — ^It is notoriously hereditary ; and so long as ring- 

 boned mares are bred from, ring-bone must continue to be 

 the source of much trouble and loss to the farmer. Another 

 very common cause, which may be either a primary or 

 merely an exciting one, as the case may be, is ' the absurd 

 custom of allowing foals a few weeks old to follow the mare, 

 often for ten or twelve miles, at a brisk trOt over a hard road. 

 With such treatment, need we wonder, then, that the unsolidi- 

 fied bones of the colt should suffer from the concussion, and 

 " throw out " ring-bones, spavins, &c. 



In older animals, the cause is concussion of the bones, by 

 which inflammation is set up, followed by bony deposition. 

 In some cases, it arises from violent inflammation of the 

 ligaments of the joint, which, extending to the surrounding 

 tissues, produces the osseous enlargement. 



In some cases, we have merely two enlargements at the 

 sides of the joint ; in others, it surrounds the whole articu- 

 lation, extends to the coffin-joint, involving the whole of this 

 part of the foot in one mass of spongy bone. 



Symptoms. — An enlargement, which, on examination, is 



