he glass yellow when warm, and yellowish
green when cold; a larger addition produces a dark red color
when warm, which, on cooling, becomes yellow and finally a
brilliant green with a tinge of yellow.

in the reducing flame.

A small quantity of the oxide renders the glass beautifully
green both when warm and when cold. A larger addition changes it
to a darker emerald green. Tin produces no change in the color.

Behavior with Mic. Salt on Platinum wire

in the oxidizing flame.

Dissolves to a clear glass which has a pink tinge while warm,
but on cooling becomes dusky green, and finally brilliantly
green.

in the reducing flame.

As in the oxidizing flame, except that the colors are somewhat
darker. Tin produces no further change.

* * * * *

33. Arsenious Acid, AsO^{3}.

Behavior with Borax on Platinum wire

in the oxidizing flame.

No reaction.

in the reducing flame.

No reaction.

Behavior with Mic. Salt on Platinum wire

in the oxidizing flame.

No reaction.

in the reducing flame.

No reaction.

* * * * *

34. Tellurous Acid, TeO^{2}.

Behavior with Borax on Platinum wire

in the oxidizing flame.

Dissolves to a clear colorless glass which, when treated on
charcoal, becomes grey and dull from particles of reduced
tellurium.

in the reducing flame.

As in the oxidizing flame.

Behavior with Mic. Salt on Platinum wire

in the oxidizing flame.

As with borax.

in the reducing flame.

As with borax.

* * * * *

7. EXAMINATIONS WITH CARBONATE OF SODA.

The carbonate of soda is pulverized and then kneaded to a paste with
water; the substance to be examined, in fine powder, is also mixed
with it. A small portion of this paste is placed on the charcoal, and
gradually heated until the moisture is expelled, when the heat is
brought to the fusion of the bead, or as high as it can be raised.
Several phenomena will take place, which must be closely observed.
Notice whether the substance fuses with the bead, and if so, whether
there is intumescence or not. Or, whether the substance undergoes
reduction; or, whether neither of these reactions takes place, and, on
the contrary, the soda sinks into the c