A test for bile in the urine or other body fluid; nitric acid, with a little nitrous acid, is cautiously added to a few milliliters of the material to be tested; if bile (bilirubin) is present, it is oxidised to varying degrees, thereby resulting in disklike zones that are (from the interface outward) yellow, red, violet, blue, and green; development of green and violet layers is essential to the validity of the test.
Synonym: Rosenbach-Gmelin test.
(05 Mar 2000)