ELEMENT 8 OF HIPPoi^uGY. 83 



lameness in front, the trouble lies below the shoulder-joint. The 

 point of the shoulder marks the position of the shoulder-joint. 

 The shoulder-blade should slope well forward, towards the point 

 of the shoulder, in order to insure a comfortable seat for the rider. 

 The arm-bone articulates with the forearm-bone at the elbow- 

 joint. This joint is a little below the upper end of the leg-bone, 

 and the projection of the bone, above the joint, is called the 

 elbow. In order that the horse shall be " handy" in front, or 

 have a free action, the elbow should have considerable lateral 

 motion. The absence of this condition is termed tied down 

 to the chest. 



Sprains in the elbow-joint are very rare. All bones are 

 covered with membranes that secrete either bony tissue or fluids 

 needful to keep the bones properly moist. At the elbow and 

 hock, these membranes are not covered by muscles, but directly 

 by the skin. Inflammation, resulting from a blow to these un- 

 protected parts, is not manifested in the usual way, but by an 

 increased secretion of fluid, accompanied by a thickening of the 

 skin and membranes over the injured part. This fluid is the 

 same that is found in the familiar water-blister. When the elbow 

 is injured, the resulting "blister" is termed a capped elbow 

 (Figure 58). This trouble is found most frequently in horses 

 carelessly or ignorantly shod, and stabled on brick, concrete, or 

 granite block floors, and is due to the shoe, or the floor, striking 

 the elbow when the horse lies down. It is sometimes called a 

 shoe-boil, and, while easily removed, if taken in time,s till its 

 presence argues some weakness in the foreleg that prevents the 

 horse from easing down properly in the act of lying down; he 

 brings his elbow to the ground with more force than a perfectly 

 sound horse of good conformation should do. 



Between the leg-bone and the cannon-bone is a group of 

 small bones, six in front, called carpals, and one, larger, in rear, 

 called the trapezium (Figure 59). The joint formed by these 

 bones is called the knee. It is a hinge in the continuity of leg- 



