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circulation, even when none has been introduced along with the 

 food, we next proceeded to test the grounds upon which it had been 

 asserted that glucogen is not transformed into sugar in the healthy 

 liver during life. 



In the paper already referred to, Dr. Pavy stated that the sudden 

 abstraction of heat from the liver after its removal from the body, 

 checks the transformation of the sugar-forming material, and thereby 

 enables us to operate on the hepatic substance while in the same 

 chemical condition as during life. The plan he recommends is to 

 sacrifice a dog by pithing, and instantly to slice off a piece of liver, 

 and throw it into a freezing mixture of ice and salt. In which case 

 he says the absence of sugar is almost complete, and thence con- 

 cludes that the presence of sugar in the liver can no longer be looked 

 upon as a ( ' natural ante mortem condition ; " but " is in reality due 

 to apost mortem occurrence." 



In the following experiments, not only was the plan recommended 

 most scrupulously followed, but even the risk of the glucogen in the 

 liver becoming transformed into sugar during the process of pre- 

 paring the decoction, was avoided by cutting the frozen liver into 

 thin slices, and allowing them, while still in that condition, to fall 

 directly into the boiling mixture of acetic acid and water. The liver 

 was in this way prevented from thawing until it entered a medium 

 as capable of arresting the transformation of its glucogen into sugar 

 as the cold. The decoction so obtained might therefore be presumed 

 to contain the soluble matters as nearly as possible in the same 

 chemical state as they were in the living organ. 



Exp. 4. A small, but full-grown dog was fed during fourteen 

 days solely on animal food. Four hours after a meal of boiled 

 horseflesh he was killed by section of the medulla oblongata. The 

 abdomen was rapidly opened, and a portion of liver cut off and 

 instantly immersed in a freezing mixture of ice and salt. A second 

 portion of liver was as speedily as possible detached, and quickly 

 washed in cold water. The latter portion was then, without loss of 

 time, cut into fragments, which were allowed to fall directly into 

 boiling acidulated water. On testing the clear filtrate, distinct evi- 

 dence of the presence of sugar was obtained. After half an hour, 

 the frozen portion of liver was taken, without being allowed to thaw, 

 and sliced directly into the boiling water with acetic acid. The 



