268 PHYSIOLOGICAL CHEMISTRY 



concentrated calcium chloride solution. The milk now clots, since 

 calcium is supplied. 



c. Gastric juice contains also a lipase, but its action is not 

 extensive. 



d. PRODUCTS OF GASTRIC DIGESTION. When the hydrochloric 

 acid stomach mucosa mixture has remained in the incubator for 

 2 or 3 days or longer, remove it, boil, filter and neutralize the 

 whole of the filtrate. Any metaprotein will precipitate. Filter 

 if necessary and saturate with solid ammonium sulphate. Pro- 

 teoses precipitate. Filter and test for peptones. Gastric diges- 

 tion takes the proteins no lower than peptones. 



III. Motor Power of the Stomach. 



a. Take by mouth a capsule containing 0.1 gm. iodoform. This 

 is not decomposed until it reaches the intestine. Test saliva for 

 iodine by spitting upon starch paper and dropping one drop of 

 cone, nitric acid upon the spot. A positive test appears in from 

 1 to l l /o hours. 



IV. Rate of Absorption From the Stomach. 



a. Take by mouth 0.2 g. potassium iodine in a capsule. Test 

 saliva at minute intervals for iodine as in III. a. A positive test 

 appears in from 10 to 15 minutes. 



b. Take by mouth a capsule containing 1 gm. of salol. In the 

 intestine this is broken up into phenol and salicylic acid. A 

 violet color imparted to the urine by a few drops of ferric 

 chloride indicates salicylic acid. A test should appear in from 

 1 to m> hours. 



