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appear that even the molecular changes arising from the sponta- 

 neous coagulation of the blood are sufficient to effect the destruc- 

 tion of normal animal sugar. And this conclusion is strengthened 

 by the fact, that in diabetic blood (the sugar of which, as would 

 appear from other considerations also, is not so susceptible of 

 metamorphosis as the healthy variety) the sugar does not disap- 

 pear to a similar extent in the clot. 



Under the changes of the decomposition of blood, normal animal 

 glucose is very readily metamorphosed. The rapidity of the meta- 

 morphosis depends on the activity of the decomposition of the 

 animal substances present, and when the destruction of the sugar is 

 complete the blood has assumed an acid reaction. 



This acid reaction of decomposing blood is only observable in 

 that which was previously pretty largely impregnated with sugar. 

 It appears to be owing to the formation of lactic acid. Certainly, 

 it cannot be due to carbonic acid, for the reaction remains after 

 exposure to a boiling temperature. 



The disappearance of sugar in the manner just pointed out does 

 not depend on the oxygen of the air, except in so far as this agent is 

 concerned in exciting the decomposition of the azotized constituents 

 of the blood ; for the sugar disappears as rapidly when there is a 

 small, as when there is a large amount of surface exposed to the air. 

 But if the air be carefully and completely excluded, no signs of de- 

 composition of the animal parts of the blood are to be observed, and 

 under these circumstances the sugar also remains. The disappear- 

 ance of sugar is more rapid where the fibrine and corpuscles are pre- 

 sent, than when the serum is exposed alone ; and in accordance 

 with this, the blood in the one case undergoes decomposition much 

 sooner than in the other a fact easily intelligible from the greater 

 amount of azotized ingredients present. 



If blood normally impregnated with saccharine matter be placed 

 aside until signs of incipient decomposition are observed, and the 

 sugar is beginning to disappear, exposure to a current of oxygen 

 rapidly completes the total disappearance of the saccharine con- 

 stituent. In this observation we have a further illustration of the 

 analogy that appears to exist, in the nature of the metamorphosis of 

 sugar as a physiological process, and that which takes place chemi- 

 cally under the influence of an azotized compound, whose elemen- 



