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The E-Sylum:  Volume 9, Number 1, January 1, 2006, Article 5

MORE ON THE U.S. MINT PANTOGRAPHIC REDUCING MACHINE

Last week Dick Johnson wrote: "To their credit,
Treasury officials turned instead to American sculptors
to create new coin designs. No small designs these.
These artists - St-Gaudens, Weinman, Fraser, MacNeil,
de Francisci - created oversize models which were
pantographically reduced."

Howard Spindel writes: "The pantographic reducing machine,
aka reducing lathe or transfer lathe, was around long
before the appearance of the above mentioned sculptors.
It was used in preparing coinage dies as early as the
mid-1800s.

An article in Harper's New Monthly Magazine, Vol 24,
Issue 139 (December 1861) details the processes in use
at the mint at the time of writing, including the use
of the reducing lathe.  You can read a copy of that
article on my local club's website at:

MakingMoney.pdf

I originally found this article at Cornell University's
The Making of America project, which is a fantastic resource.

This takes nothing away from the beauty that the early 20th
century engravers brought to our coinage, but I would say
the quality of their designs is due to their skill as sculptors,
not to use of the reducing lathe."

Dick Johnson writes: "In reply to Howard Spindel's comment
to my item on the die-engraving pantograph in last week's
E-Sylum -- Howard is correct. The pantograph has been in
use at the Philadelphia Mint since their Contimin arrived
from France in 1836. It was replaced by the Hill machine
that the mint acquired from William Wyon in London in 1857,
and the Mint acquired the Janvier in 1906.

I gave a more complete history of the die-engraving
pantograph in E-Sylum (vol 7 no 11 article 10)
March 14, 2004. You can review this at: vol 7 no 11 article 10

The difference was in HOW the American engraving staff
at the Philadelphia Mint used these machines. From 1836
well into the 20th century the engravers would only use
the Contimin or Hill to make device punches of the main
device. A master pattern would be made of the Liberty
Seated or Liberty Head, say, and this could be reduced
for each size required for the dime, quarter, half. What
they would cut was a device punch alone -- not the entire
coin design. The device punch would then be hubbed into
a die, then add lettering, stars and dates by hand punching
(to create a master die).

It was not until 1920 that MINT engravers reproduced
the entire design, lettering and all, from one model,
de Francisci's Peace dollar design. Even though the
Philadelphia Mint department had a Janvier they did not
use this for the original models of Fraser, Weinman, and
MacNeils (they tried for St-Gaudens model but that is
another story). Galvanos of all these artists' models
were made and reduced in New York City (at Medallic Art
Company).

The artists modeled (on average)12 to 16-inch models,
Medallic Art reduced these to 9-inch patterns. What
these artists turned over to the mint were these midsize
galvanos. The mint used these galvanos to further reduce
to cut hubs and dies.

There are subtle differences from a die made by punches
and hand punched lettering, figures and stars in contrast
to a die made from one model intact. The Barber / Morgan
hand punched dies are stiff designs with sharp demarcations
of the punched elements. A modeled design is far softer
as the elements tend to blend from the lettering into the
field. It is very subtle; you have to know the technology
and what technique was used for each to see these differences.

Howard, I hope that clears up the statement I made last week.
My intent was to contrast the designs of talented sculptors
(and the use of one model intact reduced on the Janvier
pantograph) from the engraving methods of the Barber / Morgan
era."

  Wayne Homren, Editor

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