ollowing in the oxidation flame:

(1.) Whether the heated substance is fused to a clear bead or
not, and whether the bead remains transparent after cooling. The
beads of some substances, for instance those of the alkaline
earths, are clear while hot; but upon cooling, are milk-white and
enamelled. Some substances give a clear bead when heated and when
cold, but appear enamelled when heated intermittingly or with a
flame which changes often from oxidation to reduction, or with an
unsteady flame produced by too strong a blast. The reason is an
incomplete fusion, while from the basic borate compound a part of
the base is separated. As the boracic acid is capable of
dissolving more in the heat, a bead will be clear while hot,
enamelled when cold, as a part in the latter instance will become
separated.

(2.) Whether the substance dissolves easily or not, and whether
it intumesces from arising gases.

(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