106 DIGESTION. LECT. V. 



of the property which certain animal membrane* acquire 

 when kept for some time in contact with water, of convert- 

 ing large quantities of sugar into lactic acid. 



These same azotised substances, which, under certain 

 conditions, excite the lactic fermentations, when taken in 

 another state, which I shall call a more advanced stage of 

 transformation, and the nature of which up to the present 

 we are ignorant of, cease to produce lactic acid by their 

 action upon sugar ; and, on the contrary, they aid alcoholic 

 fermentation, by transforming the sugar into carbonic acid 

 and alcohol. Moreover, we know that a solution of sugar 

 injected into the veins of an animal, soon makes its appear- 

 ance in the urine. 



From our knowledge of organic chemistry, and the well 

 known results obtained by actions of contact, we may con- 

 clude that starch is convertible, in the bowels, into lactic 

 acid, by first passing into the intermediate states of dextrine 

 and sugar. 



It is neither unreasonable, nor in opposition to the pre- 

 sent state of knowledge, to suppose that a portion of sugar, 

 into which 'starch has been converted, not only suffers in the 

 intestines the lactic fermentation, but also undergoes some 

 other transformation there, analogous to that, in the midst 

 of which we now know the infusory animalcules are pro- 

 duced. 



The recent experiments of Gruby and Delafond prove 

 beyond doubt, that very large numbers of these animalcules 

 are especially found in the stomachs of herbivora. 



Diabetes. I cannot close this subject without offering a 

 few remarks on the researches which have been made to 

 discover -the cause and the curative treatment of dia- 

 betes. 



Bouchardat first broached the opinion, which has since 

 been generally adopted, that in this malady starch was 



