The insoluble salts of strontia do not produce a very intense color. Baryta does not prevent the reaction of the soluble salts of strontia, unless it exists greatly in excess. In the presence of baryta, strontia can be detected by the following process: mix some of the substance under examination with some pure graphite and water, by grinding in an agate mortar. Place the mixture upon charcoal, and expose it for a while to the reduction flame. The substance becomes reduced to sulphide of barium and sulphide of strontium, when it should be dissolved in hydrochloric acid. The solution should be evaporated to dryness, redissolved in a little water, and enough alcohol added that a spirit of 80 per cent. is produced. Inflame the spirit, and if strontia is present, the flame is tinged of a red color. This color can be discerned more distinctly by moistening some cotton with this spirit and inflaming it. If strontia or its compounds are fused with a green bead of carbonate of soda and sesquioxide of manganese, as described under the head of baryta, a bead of a brown, brownish-green, or dark grey color is produced. Carbonate of soda does not dissolve pure strontia. The carbonate and sulphate of strontia melt with soda upon platinum foil to a bead, which is milk-white when cold, but fused upon charcoal they are absorbed. Strontia or its compounds produce with borax, or microcosmic salt, the same reactions as baryta. When they are moistened with nitrate of cobalt, and ignited in the oxidizing flame, a black, or grey infusible mass is produced.