228 PHYSIOLOGICAL CHEMISTRY. 



invariably absorbed from the intestinal canal as peptones, or more 

 correctly perhaps as albumoses and peptones. But it has been 

 positively settled by the investigations of BRUCKE, BAUER and 

 VOIT, EICHHORST, CzERNY and LATSCHENBERGER, that peptonized 

 albumin, casein, myosin, and alkali albuminates cannot be ab- 

 sored from the intestines a matter which is of practical import- 

 ance, especially with regard to the nutritive clysters. If the 

 albumin can be absorbed partly as such and partly as peptone, then 

 the question arises, how much more can it be absorbed in one form 

 than in the other ? This question cannot be decisively answered. 

 The investigations by SCHMIDT-MULHEIM of the contents of the 

 stomach and intestine of dogs show that the stomach contains a 

 considerably larger amount of peptone than of simple dissolved 

 proteids, which seems to indicate that the greatest part of the pro- 

 teids is absorbed as peptones (or albumoses). 



The soluble salts are also absorbed with the water. The albu- 

 min and peptone which can dissolve a considerable quantity of 

 salts insoluble in alkaline water are of great importance in the ab- 

 sorption of such salts. 



The soluble constituents of the digestive secretions may, like 

 other dissolved bodies, be absorbed, as is demonstrated by the pas- 

 sage of peptone into urine ; the enzymes may also be absorbed. 

 The occurrence of urobilin in urine attests to the absorption of the 

 bile-constituents under physiological conditions notwithstanding 

 that, according to certain investigators (MAcMu^N), it is not 

 identical with hydrobilirubin, and contrariwise, according to the 

 observations of COPEMAN and WINSTON on a woman with a biliary 

 fistula, it also occurs in the urine when no bile comes into the 

 intestine. The question as to the occurrence of very faint traces 

 of bile-acids in normal urine is also contradicted, and from the 

 behavior of the urine it is therefore difficult to draw any positive 

 conclusion as to a possible absorption of the bile-constituents from 

 the intestine. On the other hand, the absorption of bile-acids 

 from the intestine seems to be established by other observations. 

 TAPPEINER introduced a solution of bile-acid salts of a known 

 concentration into an untied intestinal knot, and after a time 

 investigated the contents. He found that in the jejunum and the 

 ileum, but not in the duodenum, an absorption of bile-acids took 



