(3.) Whether the bead, when exposed to the oxidation flame, exhibits any color, and whether the color remains after the bead shall have cooled, or whether the color fades. (4.) Whether the bead exhibits any other reaction in the reduction flame. The bead should not be overcharged with the substance under examination, or it will become colored so deeply as not to present any transparency, or the color light enough to discern its hue. 8. _Microcosmic Salt--Phosphate of Soda and Ammonia_--(NaO, NH^{4}O + PO^{5}).--Dissolve six parts of phosphate of soda (2NaO, HO, PO^{5}), and one part of pure chloride of Ammonium (NH^{4}Cl.), in two parts of boiling water, and allow it to cool. The greatest part of the formed double salt crystallizes, while the mother-liquid contains chloride of sodium, and some of the double salt. The crystals must be dissolved in as little boiling water as possible, and re-crystallized. These crystals must be dried and powdered. When this double salt is heated, the water and the ammonia escape, while the incombustible residue has a composition similar to borax, viz., a free acid and an easily fusible salt. The effect of it is, therefore, similar to the borax. The free phosphoric acid expels, likewise, most other acids from their combinations, and combines with metallic oxides. For supports, the platinum wire may be used, but the hook must be smaller than when borax is used, or the bead will not adhere. As for all the other experiments with this salt, the microscosmic salt is used the same as borax.