in five fluid ounces of distilled water, and preserved in a bottle impervious to light.

Use. This solution has the power of coagulating albumen, with which it forms a very insoluble compound; and it yields with iodide of potassium a precipitate which is at first salmon-coloured, but soon changes into brilliant scarlet crystals, and may, therefore, be used as a test for iodide of potassium.