flame to a clear
yellow bead, which is greenish-yellow when cold. In the reduction
flame it produces a beautiful green bead, which increases when cold.

When fused upon charcoal with the addition of tin, its color is
darker. Carbonate of soda does not dissolve it, although with a very
small portion of soda it gives indications of fusion, but with still
more of the soda it forms a yellow, or light-brown mass, which is
absorbed by the charcoal, but it is not reduced to the metallic state.

(_i._) _Vanadium_ (V).--This very rare mineral is found in small
quantity in iron-ores, in Sweden, and as vanadic acid in a few rare
minerals. The metal presents the appearance of an iron-grey powder,
and sometimes that of a silver-white mass. It is not oxidized either
by air or water, and is infusible.

_Vanadic Acid_ (VO^{3}) fuses upon platinum foil to a deep orange
liquid, which becomes crystalline after cooling. When fused upon
charcoal, one part of it is absorbed, while the rest remains upon the
charcoal and is reduced to protoxide similar in appearance to
graphite.

A small portion of it fuses with borax in the oxidation flame to a
clear colorless bead, which appears, with the addition of more vanadic
acid, of a yellow color, but changes to green when cold.

In the reduction flame the bead is brown while hot, but changes, upon
cooling, to a beautiful sapphire-green. At the moment of
crystallization, and at a degree of heat by which at daylight no
glowing of the heated mass is visible it begins to glow again. The
glow spreads from the periphery to the centre of the mass, and is
caused by the heat liberated by the sudden crystallization of the
mass. It now exhibits an orange color, and is composed of needle
crystals in a compact mass.

Microcosmic salt and vanadic acid fuse in the oxidation flame to a
dark yellow bead which, upon cooling, loses much of its color.

In the reduction flame the bead is brown while hot, but, upon cooling,
acquires a beautiful green color.

Vanadic acid fuses with carbonate of soda upon charcoal, and is
absorbed.

(_k._) _Chromium_ (Cr) occurs in the metallic state only in a very
small quantity in meteoric iron, but is frequently found in union with
oxygen, as oxide in chrome iron ore, and as chromic acid in some lead
ores.

In the metallic state it is of a light grey color, with but little
metallic lustre, very hard, and not very fusible. Acids do not act
upon it, except the hydrofluoric;