Hart's Mercantile Computing Machine
Object Details
- patentee
- Hart, William
- Scovill Manufacturing Company
- Description
- The instrument consists of three concentric brass discs, a brass marker, a steel stop, and a wooden handle (instrument must be removed from box to find handle). Each brass disc has the numbers from 0 to 99 stamped around the edge. The two inner discs both have a circle of 100 holes just outside the numbers. The inner holes are used to add the last two digits of a number by rotation. Any hundreds value in the sum carries to the second set of holes, which are used to add hundreds and thousands places.
- The machine is in a cylindrical wooden case with cover.
- According to the Kirksville [Missouri] Democrat for August 2, 1888, by then Hart had sold 3500 of these devices and “he lately ordered one thousand more.”
- References: U.S. Patent #199289
- P. Kidwell, "Adders Made and Used in the United States," Rittenhouse, 1994, 8:78-96.
- Kirksville [Missouri] Democrat, August 2, 1888.
- Location
- Currently not on view
- Credit Line
- Gift of Mrs. Robert T. Kerr
- 1878
- ID Number
- 1993.0510.01
- accession number
- 1993.0510
- catalog number
- 1993.0510.01
- Object Name
- adder with carry
- Physical Description
- steel (overall material)
- brass (overall material)
- wood (overall material)
- Measurements
- overall: 5.5 cm x 13.5 cm x 13.5 cm; 2 5/32 in x 5 5/16 in x 5 5/16 in
- place made
- United States: Connecticut, Waterbury
- place patented
- United States: Missouri, Kirksville
- See more items in
- Medicine and Science: Mathematics
- Adder
- Science & Mathematics
- National Museum of American History
- Subject
- Mathematics
- Record ID
- nmah_690274
- Metadata Usage (text)
- CC0
- GUID (Link to Original Record)
- https://n2t.net/ark:/65665/ng49ca746a5-0b41-704b-e053-15f76fa0b4fa
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