720 PHYSIOLOGY OF DIGESTION AND SECRETION. 



Sugars and Peptones. Experiments by the newer methods leave 

 no doubt that sugars and peptones can be absorbed from the stomach. 

 In von Mering's work different forms of sugar dextrose, lactose, 

 saccharose (cane-sugar), maltose, and also dextrin were tested. 

 They were all absorbed, but it was found that absorption was more 

 marked the more concentrated were the solutions. Brandl reports 

 that sugar (dextrose) and peptone are not sensibly absorbed until 

 the concentration has reached 5 per cent. With these substances 

 also the ingestion of condiments or of alcohol increases distinctly the 

 absorptive processes in the stomach. Examination of the mucous 

 membrane of a stomach in full digestion shows that it contains 

 albumoses (Glaessner), a fact that indicates some absorption. 

 Direct examination of the stomach contents* indicates that the 

 products of peptic action beyond the albumose stage namely, 

 the peptones, peptids, and amido-bodies are absorbed. On the 

 whole, however, it would seem that sugars and peptones are ab- 

 sorbed with some difficulty from the stomach. 



Fats. As we have seen, fats probably undergo no digestive 

 changes in the stomach, except when eaten in emulsified form. 

 The processes of saponification and emulsification -are supposed to 

 be preliminary steps to absorption, and these processes take place 

 usually after the fats have reached the small intestine. The fat that 

 is not acted upon at all in the stomach is, of course, not absorbed, 

 and even those fats in emulsified form which are partially saponified 

 in the stomach escape absorption until they reach the small intestine. 

 * Zunz, 'Beitrage zur chem. Physiol. u. Pathol.," 3, 339, 1903. 



