Valiant Personal Calculator

This small notched band adder has six serrated metal strips arranged in columns that may be moved up and down with an aluminum stylus. The front is also aluminum, partly colored blue. The back is steel painted white, and the zeroing bar is brass. At the top front of the instrument, the six columns are used for addition and the openings are crook-shaped for carrying. As the bottom, the same strips are used for subtraction and the openings have an inverted crook for borrowing. The instrument is marked on the back: JAPAN. Compare Addiator Universal (1988.0807.04) and Addiator Arithma (1986.0543.01).
According to the donor, Kathleen Dolores Barberini used this particular Valiant Personal Calculator to maintain her household budget. Barberini believed that she used it in the 1950s. The Valiant personal calculator was advertised as selling for 99 cents in the Los Angeles Times in 1960.
Reference: Los Angeles Times, July 17, 1960, p. D4.
Currently not on view
date made
ca 1960
place made
Physical Description
brass (overall material)
aluminum (overall material)
steel (overall material)
overall: .3 cm x 4.2 cm x 16.2 cm; 1/8 in x 1 21/32 in x 6 3/8 in
ID Number
accession number
catalog number
Credit Line
Gift of Kathleen A. Robertson
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History


How does this valiant calculator work. I found one and do not know how to use it. Thanks
"The Valiant adder, like other adders, did not carry out calculations, although it assisted a user doing so. Columns on the top half of the machine were for addition. One pushed the notched band down with a stylus to enter each digit in a number. If the total in a column exceeded nine, one pushed the band up and carried, moving the stylus in the hook-shaped space. The bottom set of columns was for subtraction. One entered the first (larger) number using the addition columns. To subtract, one pulled up the notches digit by digit. The hook at the bottom of the column served for borrowing. In both cases, results showed up in the windows across the middle of the adder. See for further information."

Add a comment about this object