BONES: DISEASES AND ACCIDENTS. 



By V. T. Atkinson, V. S. 



[Revised in 1904 by John E. Mohler, V. M. D.] 



Some knowledge of the skeleton is advisable to facilitate the stndy 

 of diseases of bones and the accidental injuries to which they are 

 exposed. The skeleton of the adult ox is made up of the following 

 number of bones: 



Spinal column ._-. 45 



Head 28 



Chest ..." -.. 27 



Shoulder _. 2 — 1 on each side. 



Arm _ _ 2 — 1 on each side. 



Fore arm. _ 4 — 2 on each side. 



Fore foot 40 — 20 on each side. 



Pelvis _ - . _ 2 — 1 on each side. 



Thigh 2 — 1 on each side. 



Leg _ . _ 6 — 3 on each side. 



Hind foot 38 — 19 on each side. 



Total _ 196 



Without attempting to burden the reader with the technical names 

 and a scientific classification of each, it appears 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 (PL 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 a dense form of connective tissue impregnated with lime 

 salts and contain two elementary constituents — the organic, or animal, 

 and the inorganic, or earthy. In young animals the former predomi- 

 nates; with increasing years the relative proportions of the two change, 

 so that when advanced age is reached the proportion of inorganic far 

 exceeds 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 reparative 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 



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