American Adding Machine Model 4

This lever-set printing adding machine is manually operated. It has a plain steel case painted black. Seven levers that move in circular arcs between slots in the front of the case. The case is painted along the edges of the slots with the digits from 0 to 9 (large and in black and white) and 9 to 0 (small and in red). The large digits are used in addition, and the small ones in subtraction. A corrugation or depression in the cover marks each digit. Digits are set by placing the index finger in the corresponding depression and raising the lever by the thumb until it is stopped by the finger. They are entered by moving down a metal handle with a wooden knob on the right side. If the red clear key to the left of the levers is pressed down, moving this knob zeros the machine.
The result appears in eight windows above the levers. Another handle, on the left side, zeros digits set incorrectly (this handle is not screwed in). The printing mechanism at the back top of the machine prints up to eight digits by striking a black and red ribbon. There is no paper tape. A loose metal piece is painted black. There are four rubber feet.
The machine is marked on the front: AMERICAN (/) ADDING MACHINE (/) MODEL 4 (/) AMERICAN CAN COMPANY (/) PAT. AUGUST 27, 1912 (/) OTHER PATENTS PENDING CHICAGO, ILL. It is marked below the levers: PAY ROLL DISTRIBUTION - SEE INSTRUCTIONS. It is marked below the windows, at the top of the machine; AMERICAN. It is marked on the bottom: MODEL FOUR (/) NO-43021.
Compare 1986.0894.01. The American adding machine model 4 was made from September 1917 to May 1922, with serials numbers between 22,000 and 75,200.
According to donor Homer A. Walkup, this machine was used by his father, also named Homer A. Walkup, when he was a physician in Mt. Hope, West Virginia. Dr. Walkup acquired it in about 1920 for use in a cooperative grocery store intended as an alternative to the coal company’s store. The store lasted only about six to eight months. Formation of the store came at a time of labor trouble in West Virginia, in the era of the Battle of Blair Mountain. Dr. Walkup was enjoined by court order from going on company property, including company-owned housing. He successfully fought the court order and resumed house calls.
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1924, p. 27, 518. By 1924, American adding machines were made by the American Adding Machine Company of Chicago.
Accession file.
Currently not on view
date made
American Can Company
place made
United States: Illinois, Chicago
Physical Description
steel (overall material)
wood (overall material)
overall: 29.5 cm x 26 cm x 45 cm; 11 5/8 in x 10 1/4 in x 17 23/32 in
ID Number
accession number
catalog number
Credit Line
Gift of Charlotte A. and Homer L. Walkup
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Adding Machines
Data Source
National Museum of American History


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