The fine line is the characteristic of the various and beautiful
figures which are seen on a genuine note. This line is produced
by what is called the Geometrical Lathe. The patterns made by the
geometrical lathe are of every variety of form. They are not engraved
directly upon the bank-note plate, but on pieces of soft steel plate,
which are afterwards hardened. The impressions are then transferred
to a soft steel roller, which, in its turn, is also hardened, and the
impressions remain there, in relief. This roller is then capable of
transferring the same designs to the bank-note plate by means of the
transfer press.
In counterfeit engraving, the design is made directly upon the plate,
and not by transfer, as in the production of plates for genuine notes.
The essential difference between the two methods of production is, the
counterfeit is made by hand, and is inexact and imperfect, while the
genuine is made on geometrical principles, and is therefore exact,
artistic and beautiful.
In all the government issues the geometric lathe work is liberally
used. This should be studied carefully, as it constitutes the chief
test of genuineness.
Fine lines, of unerring exactness, never broken, are seen on the
genuine medallion heads, or shields, upon which the designation of
the note is sometimes stamped. This nicety cannot be given by hand, or
with the use of imperfect machinery. By close scrutiny the lines will
be found to break off in the pattern, or appear forked, irregular in
size, and not well defined throughout.
[Illustration]
On most counterfeits the vignettes are not well engraved, and the
portraits have a dull appearance; the letters are usually wanting in
clearness; the printing is sometimes faulty, by which some features of
the note are obscured.