66 



THE GELATIN FROM WHITE 



PREPARATION D. 



In this preparation the method of procedure was not quite 

 so elaborate as in the three preceding cases. The tendons 

 from oxen were cleaned and cut into thin transverse sections, 

 soaked for some time in water, then extracted for five days 

 with half-saturated lime-water, occasionally changed. The 

 residual tissue was next washed for ten days with water 

 slightly acidified with acetic acid, lastly with water alone. 

 It was then boiled with water for about half an hour, the 

 resultant solution being rejected, after which the collagen 

 was transformed into gelatin as in the preceding cases, except 

 that the boiling was not continued for so long a period, in or- 

 der to avoid any hydration of the elastin that might be present. 

 The gelatin was then purified as in the preceding cases. 



Analysis of the dried product gave the following results : 



I. 0.3019 gram substance gave 0.5528 gram C0 2 = 49.93 per cent C, and 



0.1754 gram KjO = 6.46 per cent H. 

 n. 0.3599 gram substance gave 0.6613 gram C0 2 = 50.10 per cent C, and 



0.2107 gram H 2 O = 6.63 per cent H. 

 TTT- 0.2181 gram substance gave 0.03865 gram N = 17.72 per cent N. 



IV. 0.1649 



V. 0.6478 



VL 1.2868 



VH. 1.2868 



VTIL 0.3640 



IX. 0.4274 



0.02902 



0.0111 



0.0241 



0.0270 



0.0010 



0.0013 



N = 17.60 N. 



BaSO 4 = 0.234 per cent S. 

 BaSO 4 = 0.266 " S. 

 BaSO 4 = 0.287 " S. 

 ash = 0.274 per cent ash. 

 ash = 0.304 " ash. 



COMPOSITION OF THE ASH-FREE SUBSTANCE. 

 (Average ash = 0.289 per cent.) 



AVERAGE COMPOSITION OF THE DIFFERENT PREPARATIONS, ASH-FREE. 



