284 DIGESTION. 



from the gall-bladder. Bile that has been freed by alcohol from 

 mucus, and from which the alcohol has afterwards been removed 

 by evaporation, may be kept for months without undergoing the 

 lactic acid fermentation ; mucus is indispensably requisite in this 

 process of fermentation, and this substance acts independently of 

 the bile, and not more slowly when alone than when associated 

 with that fluid, but a far more prolonged action is necessary than 

 within the intestinal canal. It cannot be supposed that any of the 

 lactic acid which is formed in these fermentation -experiments 

 could be saturated by the alkali of the bile ; for the quantity of 

 alkaline carbonate in bile is extremely small, and the acids, soluble 

 in ether, which are liberated by the decomposition of the bile 

 (and amongst which I could never detect lactic acid with certainty 

 after twenty-four hours' fermentation) exhibit a very strong acid 

 reaction. I found that ox-gall containing mucus, to which I added 

 sugar of milk, and which was kept at a temperature varying from 

 20 to 40, deposited in the course of two or three months a sedi- 

 ment of crystalline cholic acid (Strecker's cholacic acid) ; the 

 supernatant fluid contained an alkaline acetate and comparatively 

 little alkaline lactate. 



Lassaigne* was the first to observe that the pancreatic juice 

 does not possess the property of effecting the metamorphosis of 

 sugar. 



If we introduce a solution of grape-sugar into a tied loop of 

 gut (at about the middle of the small intestine) an experiment 

 which Funke often attempted at my suggestion we find that in 

 the course of 2, 3 or 4 hours the solution, even if.it was very 

 concentrated, has for the most part disappeared, while the intestine 

 itself is very pale and never inflamed (whereas loops of gut into 

 which solutions of chloride of sodium of moderate concentration 

 have been introduced, often exhibit a strong inflammatory 

 injection) ; the portion of fluid remaining in the loop never, how- 

 ever, exhibits an acid reaction. At the first glance this experi- 

 ment appears to be in entire accordance with the view held by 

 van den Broek and Heintz, that it is solely by the influence of 

 the bile that the metamorphosis of the sugar into lactic acid is 

 effected ; but if we simultaneously introduce bile and sugar into 

 the loop of gut, there is still, after the lapse of the above-men- 

 tioned time, no acid reaction in the remaining fluid ; it might 

 therefore be regarded as a fair conclusion, that the intestinal juice 

 is as powerless as the bile in inducing this metamorphosis, and 

 * Joura. de Cliim. m&l. 1851. No. 2, pp. 69-71. 



