344 NAVIX ON THE HORSE. 



crooked legs, and interfering will be the result. While the 

 bones are becoming ossified the animal is capable of bearing 

 its own weight without injury, and but little more. 



Bones are divided, for the purpose of description, into three 

 general classes, namely, long bones, short or thick bones, and 

 broad or flat bones. The long bones have a smooth middle 

 part, or shaft, and two heads. They embrace nearly all the 

 bones of the limbs. Their use is to give support to the horse 

 when on his feet, and they are the levers by which his body is 

 carried forward. They have many ridges, prominences, or 

 lumps, and rough places, to which ligaments and tendons of 

 muscles are attached. They admit of very great motion at 

 their joints, some joints moving in several directions and some 

 only backward and forward. 



The thick bones are very irregular in their shape ; indeed, 

 they are of almost every shape, and the most of them are quite 

 rough in their appearance. Some of them have large projec- 

 tions for the attachment of muscles, and many prominences 

 and rough i^laces for the same purpose. They also have, gen- 

 erally, several surfaces or faces for articulating, or joining, with 

 other bones. Their joints do not generally admit of much mo- 

 tion. The eight bones composing the knee are of this class, 

 and the motion of all taken together gives considerable extent 

 of forward and backward motion to that joint. 



The flat or broad bones are quite well described by their 

 name. Some of them are very large and broad, and of con- 

 siderable thickness, while others are mere scales, and quite 

 small. The bones of the head generally belong to this class ; 

 also those called the haunch-bones, and the breast-bone, or 

 sternum, and the ribs. Their uses are to protect hollow cavi- 

 ties and furnish extensive surfaces for the attachment, or fast- 

 ening, of muscles. They unite with each other by immovable 

 joints, or sutures. Some of them have places where other 

 bones unite with them by movable joints. 



Before proceeding further it will be proper to observe that 



