Mercury, or quicksilver, is known from all other metals by being
fluid at the ordinary temperature of the air. This is only owing to
its extreme fusibility, for at 72 degrees below the freezing point
of water, it also becomes solid, and may be hammered out or cut by a
knife; it is very heavy, being about fifteen-and-a-half times that of
water, so that most of the metals will float on its surface; it has
a bright lustre and is almost as white as silver. It is found both in
the fluid metallic state, and in combination with sulphur, in which
last state it is called “cinnabar;” this is a heavy mass of a deep
red color, and when ground to powder, of a most magnificent red,
and is the vermillion so well known as a pigment; this vermillion is,
however, most frequently manufactured by combining the mercury and
sulphur, both first purified, in this way a more brilliant color is
produced than can be got from the cinnabar. The metal is extracted by
heating the cinnabar with iron-filings or lime in a retort, by which
means the mercury distils over and the sulphur is left behind united
with the iron or lime.
Mercury is used for many purposes in the arts and sciences, for
barometers, thermometers, compensating pendulums for clocks, &c., and
also in the processes of water-gilding, looking glass silvering, and
in the Daguerreotype process. The combinations of mercury with other
metals are called “amalgams.”