The Croonian lectures on certain points connected with diabetes : delivered at the Royal College of Physicians / by F.W. Pavy.

  • Frederick William Pavy
Date:
1878
Catalogue details

Licence: Public Domain Mark

Credit: The Croonian lectures on certain points connected with diabetes : delivered at the Royal College of Physicians / by F.W. Pavy. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    ciple was eliminated with the first lead precipitate in the process employed. We need not, however, rest with the action of one test only. Moore's or the liquor potass^e, and Bottger's or the bismuth test, equally give a good reaction [result shown]. Fiu^ther, there is another test, which is accepted as afiording crucial evidence regarding the presence of sugar—I mean fermentation, and this may be shown to give a positive behaviour. In my early efforts I failed to obtain a reaction with this test, even although I had manipulated with urine to which I had pur- posely added sugar. I afterwards found the failure of reaction arose from the acidity of the product yielded by the process of preparation employed. It did not occur to me at first to look to this point, but Pasteur has shown that acidity opposes, whilst alka- linity favours, the occurrence of fermentation. After removing the acidity by neutralising with carbonate of soda, I found that fermentation actively proceeded. Some of the product obtained from healthy urine has been set going with washed yeast in this fermen- tation apparatus which I have devised for the appli- cation of the test. It may be seen that a consider- able amount of gas has been generated and is accu- mulated in the upper tube. I propose to show, by the action of potash, that this gas consists of car- bonic acid, and the chromic acid test will reveal the presence of alcohol in a few distilled drops from the fermented contents of the lower tube [experiment shown]. A counterpart application of the test with yeast and water was started at the same time as the other, and the result shows that only a comparatively insignificant amount of gas has been generated.