e of Phosphorus?

It is a solid, inflammable substance, which burns when in contact with
atmospheric air. It is used in various chemical experiments, and for
making matches; for various kinds of fire-works, &c. It will combine
with all metals except gold and zinc; and also with some earths. Some
animals, as the glow-worm, possess very peculiar phosphorescent
qualities.

_Phosphorescent_, having a phosphoric property, emitting
peculiar light like phosphorus.

What is Arsenic?

A heavy metallic substance, very volatile, and highly inflammable; so
caustic or corrosive to animals, as to become a violent poison in all
its states. In its metallic state it is used in several of the arts:
it is employed in the manufacture of factitious metals: it is of use
to the dyer in forming some of his colors; and for that purpose is
generally combined with potassa. It is used in the making of small
shot, and also in the manufacture of glass, to which it gives
transparency; in whitening copper; in calico printing; in the
preparation of colors for the painter; and in the working of platina,
and some other metals, to render them more easily fusible.

_Caustic_, dry, burning.

_Corrosive_, apt to corrode, to eat away, to penetrate.

How is the white powdered arsenic prepared?

By submitting the ore to a strong heat in a peculiar kind of furnace;
this produces a dark grey powder, which is again heated in close iron
vessels; this separates it from its impurities, and the arsenic is
obtained in thick, solid masses; these, by exposure to the air, fall
into a fine, white powder.

From what is the word Arsenic derived?

From a Greek word, signifying _masculine_--powerful (as a poison).
Arsenic is dug out of mines in Saxony, near Goslar; in Bohemia; in
England, in the Mendip Hills, in great quantities. It has so strong a
corrosive quality as sometimes to burn the hands and feet of the
miners; it is a deadly poison for all known animals. This poisonous
mineral is not found native in its perfect form, being generally
united with metallic ores.

What do you mean by Gems?

The word gem is used as a common name for all precious stones or
jewels; they consist of the siliceous earths; and are much valued for
their lustre, transparency, color, hardness, and rarity. There are
many different kinds of precious stones, each distinguished by its
peculiar character.

How are they divided?

Into the pellucid gems,