Définition

• Scales.  Machine for determining weight, as a balance scale. Scales have been employed to weight coins and medals, as metal for formulation of their composition, as blanks, as freshly struck pieces and as specimens for collecting, archiving or offered for sale. These scales appear in a variety of kinds:  balance beam, double or triple beam, collapsible, folding, spring scales, platform and electronic. Since individual coins or medals are fairly low in weight, as a few grams to less than a pound, the scales for their measurement are fairly small or simple. These are in contrast to scales that weigh large amounts of bullion, ingots or precious metal ore once used by mints. Calibrations of these scales are in the weighing systems used for metal commerce or local custom (see weights and weighing).
  Balances and scales at mints.  Prior to the twentieth century, when one of the functions of mints was to accept any precious metal brought to them for coinage, mints had to have balances that could accommodate large deposits. Since this was precious metal – silver, gold – it had to be accurate to fractions of a gram. Thus mints customarily had large balances for these measurements, in addition for such mundane measurements as a balance to weight individual blanks at the table in front of everyone who adjusted the weight of these planchets to a prescribed tolerance.
  At U.S. Mints balances were used well into the 20th century. Balances were more accurate and easier to maintain than scales. Until about 1875 mints often had to manufacture their own balances. At the Philadelphia Mint balances were first made by Joseph Saxton (1790-1873), an employee of the mint, and later by Henry Troemner, a German-born scalemaker of Philadelphia (established 1840). In Great Britain, sbalances  were made at the Royal Mint by William Cotton and Richard Pilcher. Commercial scale makers included James Napier in London, Baron Seguier in Paris, Paul Stuckrath in Berlin, Paul Bunge and his successor, Kuhlmann in Hamburg.
  These mint’s balance beams, interestingly, it was found could not be made of iron or steel. In time the beam became magnetized by the earth's magnetic forces (affecting its accurate measurement). The Philadelphia Mint solved this problem by making their beam of platinum. A gust of wind in the room where the weighing was made would also affect the scale, thus most were housed in glass cases.
  Automatic weighing machiness. These were really sets of several small balances used in parallel and packaged into a single frame, much like the cells in a car battery. In 1871, an Austrian machinery maker, Ludwig Seyss, developed a scale that would weight coin blanks (or struck coins) automatically. The Philadelphia Mint obtained their first Seyss automatic scale in the early 1880s, by then the mechanism was developed to accommodate ten positions – ten blanks could be weighed simultaneously. Blanks (half dollar denomination and above) would be hand fed into tubes feeding the scales. Mechanical fingers would move a blank from the tube and place it in a pan, that would register the weight and according to preset limits would place it into one of four chutes. The four divisions were: (1) underweight, (2) within tolerances, (3) slightly overweight which could be adjusted, and (4) grossly overweight.
  Divisions (1) and (4) would be sent to be remelted, (3) would be sent to adjusting, (2) would be sent to the coining room. Automatic weighing machines could also be used to weigh and count the pieces after striking, a counter could be mounted on the scales to accomplish this. Philadelphia Mint engineer Leslie A. Lambert made substantial improvements to automatic balances and these went into operation in 1910.
  Scales as counterfeit detectors.  A popular device in the 19th century was a small scale with prescribed slots in a flat balance beam, one slot for each denomination. A coin placed in a slot should balance the scale, any others were considered suspect. Interestingly, when coin issuing states in the medieval Germany debased their coins , they prohibited their citizens from owning scales.
  Modern scales.  Perhaps the most used scales outside the mint for weighing coins
  and medals is the tripple-beam balance scales (Ohaus brand). These are ideal since little can go wrong with them, they are very rugged and they can even be adjusted to perform
  specific gravity tests. This is in contrast with modern electronic scales, often with a platform, that have an electronic calibrated weight readout.
  References:                                                                                                                           
  C67 {1988} Cooper pp 205-207, 209 illus.

  excerpted with permission from

  An Encyclopedia of Coin and Medal Technology

  For Artists, Makers, Collectors and Curators

  COMPILED AND WRITTEN BY D. WAYNE JOHNSON

  Roger W. Burdette, Editor

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