were
so hard that the sculptors of those countries executed therewith large
works in the hardest greenstone, and basaltic porphyry ; their
jewellers cut, and pierced the emerald, and other precious stones, by
using at the same time a metal tool, and a siliceous powder. It is
stated that Copper mines have been worked in Anglesea from a very
remote period, and that the Romans were acquainted with the Hamlet
Mine, near Holyhead. The metal Copper when obtained'in a pure state has
a remarkable red colour. The smell of Copper is very peculiar.
Verdigris,
or the subacetate of Copper, is prepared by covering Copper plates with
the husks of grapes, after their juice has been squeezed out.
Fermentation takes place, and the Copper becomes oxidised; then by
further treatment with distilled vinegar the Subacetate of Copper, or
Verdigris, is formed. This is obtained in crystals of a deep
bluish-green colour. When powdered, and mixed with Cinnamon, its taste
very much resembles the odour thereof.
This
metal may be beaten out into very thin leaves ; when alloyed with zinc
it forms the metal leaf called " Dutch Metal," which is extensively
used for the ornamentation of toys, and of certain kinds of
gingerbread.
Sulphate
of Copper, when united with ammonia, produces magnificent blue
crystals. The large show bottles which are commonly placed in the shop
windows of chemists and druggists have generally one of their number
filled with a dilute solution of Copper, to which a slight excess of
ammonia has been added. (Ammonia abounds in the soil of the Libyan
desert. Sal ammoniac ■\Vas prepared by the priests of Jupiter Amnion,
and
