DIGESTION AND ABSORPTION. 181 



(16) The artificial digestion of milk. 



Of fresh milk take three portions of 5 c. c. each. 



(a) To one portion add 10 volumes of artif. gast. 

 juice; and place it in the incubator at 38 40C. 



() Prepare another beaker in the same way but 

 place it in a water bath at 38 40C. and keep the 

 mixture well stirred, dividing the casein coagulum 

 as fine as possible. 



(/) Place the third portion of milk in the water 

 bath. When it has become warm add a few centi- 

 grams of rennin. Fifteen minutes later add artif. 

 gast. juice. Stir as in (b.) In which of the first 

 two does digestion seem to progress the more rap- 

 idly? Does the progress or process of the digestion 

 seem to be materially different in the last two ex- 

 periments, (b) and (c) ? Have any of the obser- 

 vations made on milk digestion any hygienic sig- 

 nificance ? 



(17) The di fusibility of the products of the artificial 

 digestion of proteids. 



From the products of digestion in experiments 

 (16-b) digested milk, (15-a) digested gelatin, (15-b) 

 digested bread, and (12 d) digested egg albumun, fill 

 four dialyzers first neutralizing the acid with sodic 

 carbonate. After 12 24 hours, test the diffusate for 

 peptone. Why neutralize the liquid before filling the 

 dialyzer ? 



Have all of these indiffusible proteids been wholly 

 or in part changed to diffusible peptones by the action 

 of the artif. gast. juice? 



