Keuffel & Esser 4081-5 Log Log Decitrig Duplex Slide Rule

Description:

This 20-inch mahogany slide rule is coated with white celluloid on both sides and held together with metal end pieces. A glass indicator has plastic edges held together with metal screws. . There are LL02, LL03, DF, D, LL3, and LL2 scales on one side of the base, with CF, CIF, CI, and C scales on the slide. The right end of the slide is marked in red: © (/) K + E. On the other side of the base, there are LL01, L, K, A, D, DI, and LL1 scales, with B, T, SRT, and S scales on the slide. The left end of the slide is marked: 450243. The left end of the top and the bottom of the base are both marked: 243. Keuffel & Esser used this arrangement of scales on this model from 1955 to 1962; the serial number suggests this example was made around 1958.

The top edge of the rule is marked: PATS. PEND. MADE IN U.S.A. 4081-5 LOG LOG DUPLEX DECITRIG ® COPYRIGHT 1947 BY KEUFFEL & ESSER CO. PATS. 2,500,460 2,168,056 2,170,144 2,285,722 2,422,649. These patents were issued between 1939 and 1950. They dealt with the arrangement of scales on a slide rule, in particular so that the user could solve multistep problems without having to write down intermediate settings, and with the placement of a legend to make placing the decimal point easier.

The rule slides into an orange leather case lined with chamois. The flap is marked: K + E. Inside the flap is written: PHIL (/) KRUPEN. In 1959, model 4081-5 sold with a leather case for $50.50. Compare to ten-inch versions of model 4081, MA.318482 and MA.334387.

This slide rule was given to the Smithsonian in 1986 by the physicist Philip Krupen (1915–2001). Krupen received his BS from Brooklyn College in 1935, worked on the development of the proximity fuze during and after World War II, earned an MS in physics from The George Washington University, and spent a total of 38 years working for the U.S. government before his retirement in 1973.

References: Carl M. Bernegau, "Slide Rule" (U.S. Patent 2,168,056 issued August 1, 1939); Lyman M. Kells, Willis F. Kern, and James R. Bland, "Slide Rule" (U.S. Patent 2,170,144 issued August 22, 1939); Lyman M. Kells, Willis F. Kern, and James R. Bland, "Slide Rule" (U.S. Patent 2,285,722 issued June 9, 1942); James R. Bland, "Slide Rule" (U.S. Patent 2,422,649 issued June 17, 1947); Herschel Hunt, "Slide Rule" (U.S. Patent 2,500,460 issued March 14, 1950); Clark McCoy, "Collection of Pages from K&E Catalogs for the 4081-3 Family of Slide Rules: 4080-3 & 4081-3 Family Groups," http://www.mccoys-kecatalogs.com/KEModels/ke4081-3family.htm; Ed Chamberlain, "Estimating K&E Slide Rule Dates," 27 December 2000, http://www.sphere.bc.ca/test/ke/320-k+e_date2.jpg; K + E Price List, Applying to the 42nd Edition Catalog (Hoboken, N.J., 1959), 73; Dieter von Jezierski, Slide Rules: A Journey Through Three Centuries, trans. Rodger Shepherd (Mendham, N.J.: Astragal Press, 2000), 71–75; "Philip Krupen," The Washington Post, February 23, 2001, B07.

Date Made: 1955-1962Date Received: 1986

Maker: Keuffel & Esser Co.

Location: Currently not on view

Place Made: United States: New York

Subject: Rule, CalculatingMathematicsEngineering, General

Subject:

See more items in: Medicine and Science: Mathematics, Science & Mathematics, Trigonometry, Slide Rules

Exhibition:

Exhibition Location:

Credit Line: Gift of Philip Krupen

Data Source: National Museum of American History

Id Number: 1986.0790.03Accession Number: 1986.0790Catalog Number: 1986.0790.03

Object Name: slide rule

Physical Description: mahogany (overall material)celluloid (laminate material)glass (cursor material)metal (part material)leather (case material)Measurements: overall: 3.1 cm x 58 cm x 5.1 cm; 1 7/32 in x 22 27/32 in x 2 in

Guid: http://n2t.net/ark:/65665/ng49ca746aa-99be-704b-e053-15f76fa0b4fa

Record Id: nmah_1214612

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