Pickett Decimal-Keeper Slide Rule Instructions

This twelve-page booklet was received with 1995.0126.01. Titled "How To Use Decimal-Keeper Slide Rules," it is another of the instruction manuals Maurice L. Hartung wrote for Pickett & Eckel, Inc., a slide rule manufacturer based in Chicago and Alhambra, Calif. Hartung explained how Pickett had reduced the scales on slide rules in the Decimal-Keeper line so that one ten-inch Decimal-Keeper became equivalent to twenty ordinary ten-inch linear slide rules. These reduced scales are the scales marked with asterisks on Decimal-Keeper slide rules.
There are also instructions for locating the proper section of the scale, carrying out division, computing trigonometric functions, calculating roots, finding logarithms, and adjusting and cleaning the slide rule. The booklet is undated. Separately, it sold for 50 cents and had model number M-17.
Currently not on view
date made
ca 1960
Pickett & Eckel, Incorporated
place made
United States: California, Alhambra
Physical Description
paper (overall material)
overall: .2 cm x 14 cm x 21.7 cm; 3/32 in x 5 1/2 in x 8 17/32 in
ID Number
accession number
catalog number
Credit Line
Gift of Lawrence J. Kamm
Rule, Calculating
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Slide Rules
Data Source
National Museum of American History


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