Detection of Phosphorus
Orfila’s Method
The solid substances found in the alimentary canal are mechanically separated from the fluids present by means of a linen cloth. They are then examined by aid of a magnifying glass, and any fragments of phosphorus found separated and preserved under water. If none are discovered, the presence of phosphorescent vapors may possibly be detected by examining the materials in the dark. In any case, a portion of the suspected materials should be treated with nitrate of silver: in presence of phosphorus the materials acquire, first, a reddish-brown, then, a black color. The remaining portion is spread upon a shovel and heated: a white flame, burning at various points of the mass, and originating from the combustion of phosphorus, is observed, if this body be contained in the substances under examination. This method is evidently far from perfect.