Pickett 904-ES Decimal Keeper Duplex Slide Rule
date: label: date made
content: ca 1958-1959
name: label: maker
content: Pickett & Eckel, Incorporated
notes: label: Description
content: This aluminum duplex slide rule has a yellow coating and a clear plastic indicator. The "ES" in the model number refers to the rule's "Eye Saver" yellow color. The rule and indicator are held together with aluminum braces that have protruding grooves. The front of the rule has K, A, DF, D, and L scales, with CF, S, T, CI, and C scales on the slide. The scales are 9-1/2 inches long. The back of the rule has a D* scale, with T*, S* Cl*, and C* scales on the slide. Instead of covering the typical one decade of C and D scales, the scales with asterisks cover twenty decades, from 1010 to 10-10. These scales helped inexperienced users keep track of the decimal point. They performed their calculation first on the back, to determine the order of magnitude, and then a second time on the front, to make the answer precise to three significant figures.
label: Description
content: The front of the slide is marked: MODEL 904-ES (/) TRIG AND (/) DECIMAL KEEPER (/) SPEED RULE. A Pickett logo is at the other end of the slide, with the number 47 printed above the logo. The back of the rule is marked: PATENT (/) APPLIED FOR; DECIMAL KEEPER; PICKETT & ECKEL, INC. (/) CHICAGO 3, ILL. - ALHAMBRA, CAL. The logo on this rule is that used by Pickett from 1958 to 1962. The shape and material of the cursor and the braces suggest a date of 1957–1959. Hence, the object appears to have a rough date of 1958–1959.
label: Description
content: The donor patented an "automatic decimal point slide rule" and assigned the patent to Pickett. He also distributed Pickett slide rules through his own mail order firm of Devonics, Inc.
label: Description
content: The rule was received in a plastic bag. For somewhat related documentation, see 1995.0126.04. See also Lawrence J. Kamm, "Automatic Decimal Point Slide Rule" (U.S. Patent 2,893,630 issued July 7, 1959).
label: Description
content: References: Dieter von Jezierski, <i>Slide Rules: A Journey Through Three Centuries</i> (Mendham, N.J.: Astragal Press, 2000), 75–76, 100; Ron Manley, "Pickett 904-ES – Trig and decimal keeper," http://www.sliderules.info/collection/10inch/090/1096-pickett-904.htm; "Slide Rule Dates and Time-Lines," http://sliderulemuseum.com/SR_Dates.htm.
label: Location
content: Currently not on view
place: label: place made
content: United States: California, Alhambra
topic: label: Subject
content: Mathematics
label: Subject
content: General Calculation
label: Subject
content: Rule, Calculating
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Science & Mathematics
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content: Slide Rules
creditLine: label: Credit Line
content: Gift of Lawrence J. Kamm
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1995.0126.01
label: accession number
content: 1995.0126
label: catalog number
content: 1995.0126.01
objectType: label: Object Name
content: calculating rule
label: Object Name
content: slide rule
physicalDescription: label: Physical Description
content: aluminum (overall material)
label: Physical Description
content: plastic (cursor material)
label: Measurements
content: overall: 1 cm x 31.2 cm x 5 cm; 13/32 in x 12 9/32 in x 1 31/32 in