Researches on albumen : with special reference to albuminuria / by Robert Kirk.
- Kirk, Robert
- Date:
- [1881]
Licence: Public Domain Mark
Credit: Researches on albumen : with special reference to albuminuria / by Robert Kirk. Source: Wellcome Collection.
15/20 page 351
![the salt and acid precipitate. A single drop more produced fluidity. Hence, when these acids are used as a test they should be first diluted with 5 or 10 volumes of water, and of this dilution a few drops should be added cautiously after boiling. This salt and acid precipitate is always white, with whatever acid produced. When I reached from 5 to 10 drops of nitric acid, or 30 to 00 of hydrochloric or sulphuric acid, traces of the acid precipitate began to appear. This was red with all three acids on boiling, the colour depending almost entirely on the effect of the acids on the colouring matters of the urine, for the colour was pale in dialysed urines. When the maximum point of the reaction was passed, the quantities of acid being such that the precipitate began to diminish, the colour became yellow with nitric and sulphuric, and this was also the colour of the second fluidity (xanthoproteic reaction.) I may here remark that this is much less marked than with serum albumen, but more especially ovalbumen. The precipi¬ tate came at a low temperature with nitric acid, and was then white, but required a temperature of 60° to 80° with hydro¬ chloric or sulphuric. A comparison of ovalbumen and serum albumen, with albuminous urine (diagram YI), showed that the precipitates came with smaller quantities of acid in the case of ovalbumen than either of the other two. In all three it came first with nitric acid. In the case of ovalbumen and serum albumen, the precipitates with both hydrochloric and sulphuric acids came at a low temperature, although on boiling it was observed that traces of them appeared with smaller quantities of the acids. At the lower temperatures, however, the smaller quantities seemed to have the same effect if sufficient time were allowed. The precipitate in the case of ovalbumen began to appear at a high temperature, with 6 drops or so of hydrochloric acid, serum albumen requiring twice as much, and albuminous urine still more. But the chief difference between ovalbumen and serum albumen lay in the large amount of acid required before the second fluidity was reached with the former. It required 4 volumes of acid to 1 of ovalbumen, instead of equal volumes of each, as with the other two. From a general view of these diagrams, it will be seen ]. That all the spaces of precipitation are greater, and those of fluidity smaller, at high temperatures, although this is partly compensated by time at low temperatures. 2. All the spaces of precipitation are greater, and those of fluidity less with ovalbumen than serum albumen, and the same holds with regard to the first fluidity between the latter](https://iiif.wellcomecollection.org/image/b30576702_0015.jp2/full/800%2C/0/default.jpg)
