HYGIENE, UNSOUNDNESS, DISEASE. 265 



many cures advertised to remove the lame- 

 ness caused by a spavin and also the bony 

 growth, but nothing short of a chisel and a 

 mallet will perform that latter feat. Ring- 

 bones are likewise bony growths appearing on 

 the upper and lower pastern bones, more fre- 

 quently on the hind extremities than the front. 

 Firing and blistering comprise the treatment 

 most likely to succeed in removing the lameness 

 in both cases. Sidebones are ossified lateral 

 cartilages in the fore feet. The lateral carti- 

 lages spring from the wings of the pedal bone 

 and in their normal condition are designed to 

 aid in taking up the concussion caused by the 

 contact of the foot with the ground. The side- 

 bone takes away this aid to resilience and lame- 

 ness supervenes after a time. There is not 

 much that can be done to cure lameness caused 

 by sidebones, but in certain stages of their de- 

 velopment the cartilages may be amputated and 

 the horse get along very comfortably for a 

 time. 



Curbs are caused by the pulling apart of the 

 fibres of the sheath of the tendon on the hind 

 leg right on the back of the hock not far below 

 its point. Blistering and friction are the usual 

 methods employed to reduce the enlargement 

 and cure the lameness consequent on the rup- 

 ture of the fibres as described. Navicular dis- 

 ease is caused by a roughening of the sesamoid 

 bone over which the large tendon plays at the 



