CHAPTER XIII. 

 EXAMINATION OF BONE. 



POUR 10 cc. of water upon some pieces of hollow bone 

 (about 3 g.) in a beaker, add 10 cc. of hydrochloric acid 

 (evolution of carbon dioxide follows the addition of the 

 acid), and let stand at room temperature for twenty-four 

 hours. The dilute hydrochloric acid dissolves the inorganic 

 constituents of the bone and leaves the ossein, which retains 

 the shape of the original bone, undissolved. 



I. OSSEIN AND GELATIN (GLUTIN). 



Pour off the hydrochloric acid solution and preserve for 

 further investigation (under III). Wash the ossein several 

 times with water, then let it lie in water containing a few 

 drops of sodium carbonate solution and again wash with 

 water. Place it in a beaker with a small quantity of water, 

 heat this to boiling, and continue the boiling until the pieces 

 of ossein have for the most part dissolved (five to ten minutes) l . 

 Neutralize or make the solution faintly alkaline with sodium 

 carbonate solution, decant into a test-tube, and place this in 

 cold water. After some time the solution will form a more 

 or less firm jelly of bone-gelatin (also called glutin). The 

 ossein is converted into gelatin or glutin by boiling with 

 water. 



1 Frequently there remains an inner part of the bone, which was not 

 attacked by the acid. 



137 



