CHAP. XII.] ABSORPTION IN THE COLON. 453 



Czerny and Latschenberger 1 . Trie latter observers from observations 

 made on a ca^e in which a preternatural anus existed in the left. 

 inguinal region, communicating' with the sigmoid flexure, came to the 

 conclusion that soluble albumin undergoes no change when brought 

 in contact with the human large intestine, but is absorbed as such. 

 Every circumstance which leads to an irritation of the gut hinders 

 absorption. Their experiments led them however to form an estimate 

 that the whole large intestine could only absorb 6 grammes of 

 albumin in the space of 24 hours a quantity quite insufficient to 

 support the life of man. It seems obvious that the discrepancy 

 between these results and those of other observers is to be explained 

 by the fact that the conditions of the case studied by Czerny and 

 Latschenberger permitted only the rectum to be filled with liquid, 

 and that in all probability absorption goes on much more rapidly in 

 the parts of the colon situated higher up. 



In a research of great interest which he performed with the aid 

 of a patient with a preternatural anus communicating with the 

 ca3cum, Marckwald, besides shewing that the secretion of the colon 

 possesses neither diastatic nor proteolytic power, determined that the 

 whole large intestine is only capable of absorbing about 250 grammes 

 of water in the course of 12 hours. Curiously, in the case observed 

 by him, solution of albumin did not appear to be absorbed, and 

 peptones gave rise to great irritation 2 . If we consider the non- 

 absorption of albumin and peptones observed by Mackwald by the 

 aid of the information supplied by previous observers, to wit, that all 

 irritation of the large intestine seems to arrest the absorption of 

 dissolved albuminous bodies (not apparently the absorption of NaCl), 

 we shall arrive at the conclusion that his anomalous results were 

 probably due to a morbid condition of the large intestine, existing in 

 his case. 



SECT. 4. THE MICRO-ORGANISMS OF THE COLON AND THEIR 

 PRODUCTS. THE CONVERSION OF THE CONTENTS OF THE 

 COLON INTO FAECES. 



When the intestinal contents reach the ilio-caBcal valve they 

 contain no longer either pepsin or trypsin. We have discussed the 

 destruction of the former, and with reference to the latter we can 

 have no doubt that it is gradually destroyed by the organic acids of 

 the small intestine. We have adduced the concordant testimony of 

 several most competent observers who have shewn that no enzymes 

 are formed in or secreted by the mucous membrane of the large 



1 v. Czerny and T. Latschenberger, 'Physiologische Untersuchungen uber Ver- 

 dauung und Resorption im Dickdarm des Menschen,' Virchow's Archiv, Vol. LIX. 

 (1874), pp. 161190. 



- Max Mackwald, 'Ueber Verdauung und Resorption im Dickdarme des Menschen' 

 (Aus d. phys. Inst. von Prof. Kiihne zu Heidelberg), Virchow's Archiv, Vol. LXIV. (1875), 

 pp. 505539. 



