Behavior with Mic. Salt on Platinum wire

in the oxidizing flame.

As with borax, but less intensively colored. During cooling the
color becomes somewhat paler.

in the reducing flame.

As in the oxidizing flames.

* * * * *

7. Oxide of Nickel, NiO.

Behavior with Borax on Platinum wire

in the oxidizing flame.

Colors intensely. A small amount of oxide affords a glass which,
while warm, is violet, and becomes of a pale reddish-brown on
cooling. A larger addition produces a dark violet color in the
warm and reddish-brown in the cold bead.

in the reducing flame.

The oxide is reduced and the metallic particles give the bead a
turbid grey appearance. If the blast be continued the metallic
particles fall together without fusing, and the glass becomes
colorless. This reaction is readily obtained with tin upon
charcoal, and the reduced nickel fuses to a bead with the tin.

Behavior with Mic. Salt on Platinum wire

in the oxidizing flame.

Dissolves into a reddish glass which becomes yellow on cooling.
With a large addition of the oxide, the glass is brownish while
hot, and orange when cold.

in the reducing flame.

On platinum wire the nickeliferous bead undergoes no change.
Treated with tin upon charcoal, it becomes at first opaque and
grey, and after long continued blowing the reduced nickel forms
a bead, and the glass remains colorless.

* * * * *

8. Oxide of Zinc, ZnO.

Behavior with Borax on Platinum wire

in the oxidizing flame.

Dissolves easily into a clear colorless glass, which, when much
oxide is present, may be rendered opaque and flocculent by an
intermittent flame, and becomes so spontaneously with a still
larger addition. When a considerable quantity is dissolved, a
glass is obtained which is pale yellow, while hot, and colorless
when cold.

in the reducing flame.

On platinum wire the saturated glass becomes at first opaque and
grey, but by a sustained blast is again rendered clear. On
charcoal the oxide is gradually reduced; the metal is
volatilized and in crusts the charcoal with oxide.

Behavior with Mic. Salt on Platinum wire

in the oxidizing flame.

As with borax.

in the reduci