452 ABSORPTION IN THE COLON. [BOOK II. 



small intestine, processes of fermentation may help to render soluble 

 some fractions of the food constituents which had remained unacted 

 upon. 



Not only does the large intestine possess the power of absorbing 

 the soluble albumins, the peptones, the sugars, and a great part of 

 the water present in the intestinal contents which pass through the 

 ilio-colic valve, but (as first demonstrated by the experience of 

 medical men) it possesses even in its lowest part, the rectum, powers 

 of absorption which enable life to be supported for long periods of 

 time by rectal injections (nutrient enemata), when no food can enter 

 the system by the usual channels. 



The re- I n 1869, in a research conducted under Voit's 



Bauer" 58 f direction, Bauer 1 shewed that if dogs are kept without 

 food for some days, and when the daily excretion of 

 urea has become constant, rectal injections of albuminous substances 

 are made, the amount of urea excreted increases at once, proving 

 that the albumin has actually entered the economy. Having, in a 

 similar manner, injected solutions of so-called peptones (doubtless 

 composed almost entirely of albumoses), Bauer found that these 

 were most readily absorbed; an increase of urea, amounting to 

 eight grammes, occurring. This quantity of urea represented the 

 absorption of 21 grammes of dry albumin or 100 grammes of fresh 

 meat. Curiously, Bauer found that a solution of white of egg was 

 not absorbed, unless mixed with sodium chloride. On the other hand, 

 a solution of syntonin was absorbed as readily, or nearly so, as one of 

 peptones. 



The re- I n 1871 Professor Eichhorst of Zurich 2 , then a 



student of medicine in Konigsberg, published the 

 results of a research, conducted under the direction of 

 Professor von Wittich, which established, Istly, that the mucous 

 membrane of the large intestine formed neither a diastatic nor a 

 proteolytic ferment: 2ndly, that the large intestine possesses the 

 power of absorbing Meissner's a-, b-, and c- peptones (i.e. albumoses 

 and peptones), Liebig's extract of beef, the albuminous bodies of 

 milk, dissolved myosin, dissolved alkali-albuminate, egg albumin 

 mixed with common salt, and solution of gelatin : 3rdly, that it is 

 unable to absorb pure white of egg, syntonin solutions, the albumin 

 of blood serum as well as undissolved fibrin, syntonin and myosin. 



The researches of Bauer and of Eichhorst received confirmation 

 and valuable practical application at the hands of Leube 3 as well as of 



1 J. Bauer, 'Ueber d. Aufsaug. im Dick- und Diinndarm,' Zeitschr. f. Biologic, Vol. 

 v. (1869). 



2 Hermann Eichhorst, Cand. Med. aus Konigsberg, 'Ueber die Eesorption der 

 Albuminate im Dickdarm' (Von der med. Fakultat der Albertus-Universitat zu 

 Konigsberg mit dem Preise gekront), Pfliiger's Archiv, Vol. iv. (1871), pp. 570 662. 



3 W. 0. Leube, 'Ueber die Ernahrung der Kranken vom Mastdarm aus,' Deutsch. 

 Archiv f. klin. Medizin, Vol. x. (1872), pp. 154. 



