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out of the melt, 3


Plate XI. Fig. 6.—Morphine 1 : 200.
Crystals formed with Wagner’s reagent (x150).

Wagner’s Reagent. — A very characteristic test, though not so sensitive as the one with Marme’s reagent. A heavy, amorphous precipitate forms reddish-brown drops before crystallization takes place, and from the precipitate crystallization takes place very slowly.It is often necessary to allow the solution to stand several minutes before crystals are formed. The crystals are large plates, reddish-brown in color, and irregular in outline. Optimum concentration is about 1 : 200.
page 56.

Charles H. Stephenson. Some Micro-chemical Tests for Alkaloids. Including C. E. Parker, Chemical Tests of the Alkaloids Used. With Twenty-seven Plates (162 Photomicrographs) and a Folding Table of Reactions. London, 1921

out of the melt, 1 and
out of the melt, 2

10 March 2013
tags: alkaloids; photo micrographs; precipitates; rounds