The Veterinary Science 



part I. 



ANATOMY OF THE HORSE. 



CHAPTER I. 

 BONE. 



BONES are hard, yellowish-white, insensitive objects 

 which form the skeleton of animals. Living bone is 

 bluish pink, insensitive and elastic. Exposure to air 

 causes it to become diseased and blackened, very sensi- 

 tive and painful. 



Bones are made up of two kinds of matter — animal, 

 which makes the bone tough and elastic, and earthy, which 

 makes it hard and brittle. In young animals the animal 

 matter forms one-half of the substance, which afterwards 

 diminishes to one-third as the animal advances in age. This 

 is why old animals' bones are easier to fracture and harder 

 to mend. 



1. Covering of Bone. — Bones are covered by a tough, 

 fibrous, inelastic membrane called periosteum, which can be 

 seen by examining the bone of an animal which has just died. 

 The only exception to this is at the 'joints where one bone 

 articulates with another, and where a tendon or muscle plays 

 over a bone ; here we find its place taken by articular carti- 

 lage. 



2. Contents of Bone. — Red marrow is found in the ex- 

 tremities or near the ends of bones, while white marrow is 

 Found in the shaft. 



3. Classes of Bone. — Bones are classed as long, flat and 

 irregular. Long bones are found in the extremities or legs, 

 and serve as levers for traveling and pillars to support the 

 body. It is well to remember, that each long bone is divided 

 into a shaft and two extremities. Flat bones are found where 

 vital organs need protection. Example: Shoulder blade and 

 ribs, to protect the heart and lungs ; pelvic or hip bones, to 



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