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- Combination rule and postal scale
Combination rule and postal scale
Object Details
- Description
- The "Combination Rule and US Postal Scale" incorporates a desktop balance with a ruler on the back. It is a steelyard type scale with the fulcrum (two fixed, metal feet measure approximately 3/8 inch high) set at the 11 1/2-inch mark of the 18-inch ruler and the sliding weight is integrated into the long arm for easy adjusting to determine equilibrium and weigh the item suspended from the hook at the 16-inch mark. This eyehook was used to attach a small piece with a tongue designed to hold a letter or other item. The piece is missing from this object.
- The weight sits in the hollow wooden frame and can be moved up and down the scale to determine the weight of the mail. The scale measures at half-ounce increments which are marked for postage rates for first-class letters as well as third-class and fourth-class mail. The letter rates are marked in 3-cent increments up to 42 cents, paper rates up to 4 cents, and merchandise rates up to 7 cents. The scale’s maximum capacity is seven ounces.
- This device follows the design specifications of Stephen E. Barton’s patent 243,753 granted on July 5, 1881. Production of this particular model likely happened within a brief window between 1881 and 1883. As of October 1, 1883, the Post Office Department reduced postage rates to 2-cents per half ounce. This would not have rendered the scales obsolete, but would have made it less convenient for postal patrons to use. The 1885 rate increase to 2 cents per whole ounce would have incurred more conversion calculations.
- Reference:
- https://www.google.com/patents/US243753 (Accessed September 4, 2015). The patent drawing page includes a witness signature by Clara Barton, aunt of the patent holder Stephen E. Barton.
- Data Source
- National Postal Museum
- Date
- 1881-1883
- Object number
- 0.239019.1
- Type
- Commercial Products
- Medium
- wood; metal (brass); paper; adhesive; ink
- Dimensions
- Height x Width x Depth: 1 1/4 × 18 1/8 × 3/4 in. (3.18 × 46.04 × 1.91 cm)
- Place
- United States of America
- See more items in
- National Postal Museum Collection
- Record ID
- npm_0.239019.1
- Usage
- CC0