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NIST Museum & Archives

Pear Shaped Weights

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Two one pound weights sitting on top of wood boxes

These weights – 1 lb troy (left) and 1 lb avoirdupois (right) – were part of a group of five weights made in England and procured by the instrument-maker, William Simms, for the United States in 1837.

Created March 30, 2017, Updated January 11, 2018
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