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in the other cases, was not allowed to thaw before being put into 

 boiling water, the decoction was found to reduce the copper readily. 



On opening the stomach, nothing was found in it except some 

 neutral mucus. The intestines were equally destitute of food, and 

 in the rectum only a very small quantity of faeces was found ; so 

 there could be no doubt as to the animal being in a fasting con- 

 dition. 



The only point now remaining, was to determine quantitatively 

 the increase in the amount of sugar in the liver after its removal 

 from the body, and for that purpose we preferred operating on an 

 animal fed on a mixed diet. 



Exp. 7. A small dog, which had been previously fed on animal 

 diet, received a full meal of bread and milk. Five hours afterwards 

 the animal was pithed, and a portion of the liver rapidly sliced off 

 and immersed in a freezing mixture. A ligature was placed on the 

 portal vein, and its blood collected before the circulation had 

 ceased. 



On examination, this blood was found to contain a small quantity 

 of sugar, derived no doubt from the food. Bernard, I believe, has 

 erred in supposing that all the saccharine matter found in the animal 

 organism is formed out of the glucogen produced in the liver. This, 

 no doubt, is the case in the carnivora when the diet is restricted to 

 food inconvertible into sugar in the alimentary canal, but cannot be 

 regarded as the natural state of things either in the omnivora or 

 herbivora ; for the food of the latter not only contains sugar, but its 

 amylaceous elements may be converted into that substance in the 

 process of digestion. The sugar found in the bodies of animals fed 

 on a mixed diet ought therefore to be regarded partly as the direct 

 product of the food, and partly as derived from the glucogen formed 

 in the liver. 



Bernard's chief argument against this view is founded on the fact 

 that the livers of dogs fed on a mixed diet contain no more sugar 

 than those fed on purely animal food. In my opinion, however, 

 this fact is not sufficient to decide the question ; for, as the 

 liver does not store up sugar, the quantity it at any time contains is 

 no criterion of the amount produced in it. Moreover, the sugar de- 

 r ived from the food need not be expected to be found in the liver. 

 Had Bernard gauged the sugar present in the blood, instead of that 



