BONES-DISEASES AND ACCIDENTS. 



By the late V. T. ATKINSON, V. S., 



Professor of Veterinary Science, Wisconsin State University, ex-State Veterinarian, 



Wisconsin, etc. 



To facilitate the study of diseases of bones and the accidental injuries 

 to which they are exposed, some knowledge of the skeleton is advisable. 

 The skeleton of the adult ox is made up of the following number of bones : 



Spinal column 43 



Of the head 28 



Of the chest 27 



Of the shoulder 2 1 on each side. 



Of the arm 2 1 on each side. 



Of the fore arm 4 2 on each side. 



Of the fore foot 40 20 on each side. 



Of the pelvis 2 1 on each side. 



Of the thigh 2 1 on each side. 



Of the leg 6 3 on each side. 



Of the hind foot 38 19 on each side. 



Without attempting to burden the reader with the technical names 

 and a scientific classification of each, I deem it desirable to describe 

 some of the characteristics of forms in general, and of a few classes 

 into which they may be divided, leaving the special study of individual 

 bones to the illustrations of the skeleton (Plate xxv), which will serve 

 better than any amount of writing to fix in the mind of the reader the 

 location, relation, and function of each one. In early fetal life the 

 place of bone is supplied by temporary cartilage, which gradually 

 changes to bone. For convenience of study, bones may be said to be 

 composed of two elementary constituents the organic or animal and 

 the inorganic or earthy. In young animals the former predominates; 

 with increasing years the relative proportions of the two change, 80 

 that when advanced age is reached the proportion of inorganic far ex- 

 ceeds the organic. The gradual change with advancing years from 

 organic to inorganic has the effect of rendering the bone harder and more 

 brittle, and though it is stronger the reparatory process is slower 

 when injury does occur. 



The bones are nourished in two ways: first, from the outside through 

 their covering, called the periosteum the thin strong membrane that 



281 



