Renal affections : their diagnosis and pathology / by Charles Frick.

  • Charles Frick
Date:
1850
Catalogue details

Licence: Public Domain Mark

Credit: Renal affections : their diagnosis and pathology / by Charles Frick. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    as an albuminate of soda, from which combination the acid precipitates it on account of its affinity for the soda, and the alcohol for the water, which holds it in solution. This coagulation by heat may be observed in a spoon or a simple vial; yet if the quantity be very minute it may escape ob- servation when these means only are used. A small glass test-tube heated over a spirit-lamp, or plunged into boiling water, will obviate this difficulty, and should therefore be used. The white cloud formed under these circumstances is due either to the presence of albumen, or to an excess of phosphates. These latter are only deposited by heat when they are in so great an excess that anything which disturbs the relation between them and the water in which they are dissolved, causes them to be precipitated. Heat acts in this way, by increasing the space between the atoms of water, and also by producing currents in different direc- tions. But as we before remarked, the nature of the de- posit, as well as its solubility or insolubility in nitric acid, allows us readily to distinguish between the two. The de- posit in the first case is flaky, in the second crystalline; and phosphates are soluble in nitric acid, while albumen is insoluble. We must not however always conclude that when heat produces a deposit which nitric acid dissolves, that the pre- cipitate is necessarily albumen; for in many cases if a drop or two only of the acid be added, albumen will be dis- solved as well as the phosphates; but the difference is easily ascertained, for on adding a few drops more the albumen is thrown down while the other remains in solution. It often 4
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