LECTURES AND ESSAYS. 471 



place: but when this occurs the lameness, in the majority of instances, sub- 

 sides, and the enlargement, to a greater or less extent, disappears. 



The Cause, 



or rather the causes, of this disease may first of all be included under two 

 heads — the one being hereditary or predisposing, the other being exciting. 

 Of the former it may be said that some sires are notable for the number of 

 ring-boned colts they get ; but the fault is not always on the sire's side, for 

 the dam is often to blame, and breeders of experience will refuse to breed 

 from diseased mares, unless, indeed, the condition has been caused by some 

 external injury, as, for instance, the tread from the sharp calk of the oppo- 

 site shoe. So those who persist in breeding from ring-boned mares will be 

 often gratified to find that their colts are affected with this disease before 

 they are asked to do a day's work, the probably miserable creature becoming 

 a thorn in the owner's side from the day of its existence. 



Then of those which are born predisposed to ring-bone, the conformation 

 has to be considered, and it will be found that those horses with upright 

 pasterns, if used for fast road purposes, are likely to throw out ring-bones. 

 The reason why this style of conformation should render such animals more 

 susceptible to the disease is because the column of weight being more in a 

 straight line than in those animals with oblique pasterns, the concussion 

 caused by pounding on a hard road is much greater, which sets up irritation 

 in the part, which in its turn is followed by inflammation and bony deposit. 

 But not only does concussion produce this disease, for it is often the result 

 of a strain, and this is perhaps the common exciting cause when it is found 

 in the hind leg. Of the exciting cause it may be said that hard work of any 

 kind is liable to produce this complaint, such as severe galloping, trotting, 

 jumping, over-driving colts, allowing colts to follow their mothers for a 

 considerable distance (say miles to market) upon the hard road. The con- 

 cussion thus set up in the young bones, before they have properly 

 matured, is also thought to be a fertile source of this disease, and it is some- 

 times the result of external injury. It is also more likely to occur in those 

 animals whose pasterns are unnaturally long and oblique, for the increased 

 amount of leverage occasioned by such conformations is almost certain to 

 produce too severe a strain upon the parts where animals, especially young 

 ones, are called upon for an extra effort. Standing on one foot while the 

 opposite one is undergoing a course of treatment sometimes produces the 

 complaint. 



Symptoms. 



The disease will be found oftener affecting the hind feet than the fore, 

 showing clearly that severe strains have much to do with its production. 

 The gait of the animal lame from this complaint is peculiar and varies 

 much, according to the limb affected. If, for instance, the disease occurs 

 in the front leg, it will be observed that while the animal is progressing it 

 will bring its heel to the ground first ; while, if the hind leg is affected, 

 the toe will come to the ground first. This difference in progression is very 

 well marked, and can be readily seen by the most casual observation, but 

 is a circumstance which must be borne in mind during the treatment, or 

 efforts to alleviate the suffering of the animal. In the early stages of the 



