126. Gold and silver moulding. Many of the mouldings used by
jewellers consist of thin slips of metal, which have received
their form by passing between steel rollers, on which the pattern
is embossed or engraved; thus taking a succession of copies of
the devices intended.
127. Ornamental papers. Sheets of paper coloured or covered
with gold or silver leaf, and embossed with various patterns, are
used for covering books, and for many ornamental purposes. The
figures upon these are produced by the same process, that of
passing the sheets of paper between engraved rollers.
Of copying by stamping
128. This mode of copying is extensively employed in the
arts. It is generally executed by means of large presses worked
with a screw and heavy flywheel. The materials on which the
copies are impressed are most frequently metals, and the process
is sometimes executed when they are hot, and in one case when the
metal is in a state between solidity and fluidity.
129. Coins and medals. The whole of the coins which circulate
as money are produced by this mode of copying. The screw presses
are either worked by manual labour, by water, or by steam power.
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