which
cannot be done with any other hearbs, or simples or spices. And
herewith will we finish this Preface, and write of the names of the Metalls which are occupied in this Arte."
By
the ancient writers each of the nobler metals was associated with its
particular precious stone, and with its special planet. Thus, Gold was
ascribed to the Diamond, and dedicated to the Sun ; Silver was ascribed
to the Crystal, and dedicated to the Moon ; Copper to the Amethyst, and
dedicated to Venus ; Lead to the Turquoise, and dedicated to Saturn;
Tin to the Carnelian, and dedicated to Jupiter ; Quicksilver to the
Loadstone, and dedicated to Mercury ; Iron (an ordinary metal) to the
Emerald, and dedicated to Mars.
In
the Middle Ages a prevailing chemical theory about metals ran thus
:—The metals were considered to be composed of Sulphur, and Mercury.
These substances (themselves compounds) were reckoned elementary in
the composition of metals. Sulphur represented their combustible
aspect, and also that which gave them their solid form ; while Mercury
was that to which their weight, and powers of becoming fluid, were
owing. This theory was due to two main facts. Most ores of metals,
especially of copper, and lead, contain much sulphur, which can either
be obtained pure from them, or be recognized by its smell when burning.
This gave rise to the sulphur theory; while the presence of mercury was
inferred doubtless from the resemblance of the more commonly molten
metals, silver, tin, and lead, to quicksilver. So that the properties
of each metal respectively were put down to the presence of these two
substances.
