The illustration on the right is a photograph of the hind quarter of 

 ST. SAVIOUR, a thoroughbred stallion, showing a clean, strong hock and 

 properly set hind leg. The photograph on the left shows a curb on the 

 right leg due to a weakly supported hock also improperly set. 



The left illustration shows a hind leg too straight, while the right 

 one shows the other extreme in being set too far back. 



