Researches on albumen : with special reference to albuminuria / by Robert Kirk.

  • Kirk, Robert.
Date:
[1881]
Catalogue details

Licence: Public Domain Mark

Credit: Researches on albumen : with special reference to albuminuria / by Robert Kirk. Source: Wellcome Collection.

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    that it is only at certain intervals they become so pronounced that we can fully appreciate the difference, and it will be sufficient to single out two or three for especial notice. And first of all let me request your attention to the resultant a-p which bisects the angle S A c. This is the resultant of the two forces when they are equally balanced, and it is that which produces perfect precipitation of the albumen. With this resultant we have the perfect flaky or curdy precipitate, and a clear supernatant liquid, and this is the result which should always be attained when we use heat and acid as a test. But if the acid be in excess, and the resultant inclines towards A c, as the line A-P G, the precipitate undergoes a change, the flakes becoming viscid or gelatinous, until finally, with a sufficient amount of acid, the flakes are lost sight of altogether, and the precipitate becomes a homogeneous, gelatinous mass. This precipitate does not settle down, nor become visible for some time—it may be several hours after boiling. During the boiling, and for some time afterwards, the albumen appears to be in perfect solution, but it is found that it does not pass through the filter, and that it throws down this gelatinous precipitate after a length of time. This precipitate may generally be obtained with 20 to 30 minims of acetic acid. It will be observed that this reaction resembles that shown by the form of albumen to which Bence Jones has given the name of metalbumen. If the acid be in still greater excess, we have the resultant A-A F, or what we may call the acid fluidity, the albumen now giving no precipitate whatever. If we now add salt beyond the proportion which gives the flaky precipitate and produce such a resultant as A-P s, the precipitate becomes sandy or finely granular. This is better seen in albuminous urine than with ovalbumen or serum albumen. In the latter two a very little salt alone coagulates the albumen, and the precipitate takes the form of lumps or masses, the entire liquid becoming extremely viscid. But if an albuminous urine be neutral, it will seldom coagulate on boiling, even with large quantities of salt, and I have met with instances in which, after saturation with salt, it refused to coagulate on boiling till the acidity was made greater than before. Sometimes, however, I have found the neutral urine to precipitate, wholly or partially, after saturation with salt. It has sometimes appeared to me that the after dinner urine was more prone to clo so than the morning urine, but I would not speak positively on this point, as the greater quantity of albumen in the urine in the former case may have had a good deal to do with the result. But if any change in the pro-