In the second half of the 19th century, several American inventors proposed adding machines operated by moving levers, rotating discs or turning screws with the fingers. At the time, they were required to submit models of their inventions to the U.S. Patent Office. Some of these models survive in the collections shown here. At least one of them, the Lang Sales Register, apparently was manufactured.
Several of these inventors took out other patents for other inventions. The most notable was Frank S. Baldwin, who invented a pinwheel calculating machine and whose ideas were the foundation of the products of the Monroe Calculating Machine Company.
Perhaps the most successful finger-operated machines were those made by the Adding Machine Division of the American Can Company of Chicago, beginning in 1914. Even this product was not entirely successful – in 1922, the printing version of the machine was discontinued and manufacture switched to the American Adding Machine Company, also of Chicago.
"Adding Machines - Finger-Operated" showing 1 items.
- This U.S. patent model for a lever-set non-printing adding machine has a frame of two brown round end pieces joined by a central shaft and by two pieces of brass at the outside. The shaft carries six toothed wheels that may be rotated with the fingers. Each wheel has 30 teeth and is joined to a brass ring on its right. Around the rim of each ring is a slip of paper with the digits from 0 to 9 printed on it three times. One third of each ring is covered by a metal piece which has a window at the bottom and the digits from 1 to 9 engraved on it. To enter digits, wheels are rotated forward the distance indicated by these digits. Through the action of a carry mechanism, the total appears in the windows.
- Milton C. Jeffers, who took out this patent in 1863, was a resident of New York, N.Y. He is probably the Milton C. Jeffers who lived from about 1823 until dying in New York City in 1896, and who took out two further patents for agricultural machinery. A Milton C. Jeffers is listed in New York City directories of the period as an agent and as a broker.
- U.S. Patent 40,105, September 29, 1863.
- U.S. Patent 74,379, February 11, 1868.
- U.S. Patent 108,484, October 18, 1870.
- Currently not on view
- date made
- Jeffers, Milton C.
- Jeffers, Milton C.
- ID Number
- accession number
- catalog number
- Data Source
- National Museum of American History, Kenneth E. Behring Center