Pickett 904-ES Decimal Keeper Duplex Slide Rule

Object Details

Pickett & Eckel, Incorporated

Description

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.

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.

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.

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).

References: Dieter von Jezierski, Slide Rules: A Journey Through Three Centuries (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.

Location

Currently not on view

Credit Line

Gift of Lawrence J. Kamm

ca 1958-1959

ID Number

1995.0126.01

accession number

1995.0126

catalog number

1995.0126.01

Object Name

calculating rule

slide rule

Physical Description

aluminum (overall material)

plastic (cursor material)

Measurements

overall: 1 cm x 31.2 cm x 5 cm; 13/32 in x 12 9/32 in x 1 31/32 in

place made

United States: California, Alhambra

See more items in

Medicine and Science: Mathematics

Science & Mathematics

Slide Rules

National Museum of American History

subject

Mathematics

General Calculation

Rule, Calculating

Record ID

nmah_690073

Metadata Usage (text)

CC0

GUID (Link to Original Record)

http://n2t.net/ark:/65665/ng49ca746a5-1ca4-704b-e053-15f76fa0b4fa