Index by Makers & Retailers

An image of various slide rules from the collection of the Division of Medicine and Science at the National Museum of American History.

Hundreds of companies around the world were involved in the production of slide rules from the 18th to the 20th centuries. Click on one of the names below to see the objects in this collection that were associated with that firm.

Acu-RuleFelsenthalMakeba
Adams, Bertram E.Fowler & Co.Multi Slide Instrument Corp.
Albree, G. NormanFullerM. W. Kellogg Company
AlcoGeorgia Iron WorksNegus, T. S. & J. D.
Alteneder & Sons, Theo.GilsonNeil A. Maclean Company
Aston, ThomasGraphic Calculator Co.Nestler
Bastian BrothersGrindsted ProductsNovotni
Bradburn & SonGuedonOle Jorgensens Creative Workshop
Carbic LimitedGurley, W. & L. E.Ontario, Province of
Central Scientific CompanyHawthorn, RobertPerrygraf
CharpentierHemmiPickett
Charvoz-RoosIBMPost
Commonwealth Plastics Corp.ImpactPsychological Corporation
Computer Manufacturing Co.Jeppesen & Co.Remington Rand
ConciseJohn Howard Herrick Co.Richardson, George
ControllerJones, Solomon A.Ricoh
Cooke, LabanKegelman BrothersScofield, E. M.
C-ThruKeuffel & EsserScott, Walter T.
Daemen-Schmid, HeinrichKingsonStanley Rule & Level Co.
Darling, Brown & SharpeKnox, Inc.Stanley, W. F.
DatalizerK2 Publishing Corp.Sterling Plastics
Dennert & PapeLawrence Engineering ServiceTavernier-Gravet
Dietzgen, EugeneLewis & BriggsThomas, Frank J.
DIWALovelace FoundationUnique
ECOBRA  L. Lumley & Co.Whitehead & Hoag
EDMUND Scientific Co.Macbeth DaylightingWichmann Brothers
Faber, A.W. Patent Models
Search term: *:* Topic: Engineering, General Clear All

Hemmi Duplex Slide Rule Retailed by Post (Versalog 1460)

The Frederick Post Company, a 20th-century manufacturer and retailer of scientific instruments based in Chicago, did not make its own slide rules. From 1932, its exclusive supplier of linear slide rules was Hemmi, a Japanese firm.
Description
The Frederick Post Company, a 20th-century manufacturer and retailer of scientific instruments based in Chicago, did not make its own slide rules. From 1932, its exclusive supplier of linear slide rules was Hemmi, a Japanese firm. Hemmi was known for using a large-diameter variety of bamboo grown in Kagoshima Prefecture on the island of Kyushu. Company founder Jiro Hemmi (1878–1953) patented this innovation in several nations, including the United States in 1920.
While Post usually sold standard Hemmi models, around 1951 Hemmi created two ten-inch slide rules for Post, which sold in the United States as the model 1450 Versatrig and model 1460 Versalog. The Versalog was especially popular, selling several hundred thousand copies.
This example is bamboo, coated on all sides (except the ends) with white celluloid. The rule is held together with metal posts, one of which is engraved on the front: Wm. Krutz. The glass indicator has a metal frame with plastic sides. One side is marked: HEMMI JAPAN. The other side bears a Post logo in red, which has largely been rubbed away. The red Post logo and the serial number 015836 appear on the right front of the slide. The serial number indicates the rule was manufactured in 1959. This is confirmed by the date code JI on the bottom edge of the rule, which corresponds to a manufacturing date of September 1959.
The top edge of the rule is marked: CAT. NO. 1460; VERSALOG; FREDERICK POST CO.; HEMMI BAMBOO – JAPAN. The front of the base has LL0, LL/0, K, DF, D, R1, R2, AND L scales. The front of the slide bears CF, CIF, CI, and C scales. The LL/0, CIF, and CI scales are numbered in red. The back of the base has LL/1, LL/2, LL/3, D, LL3, LL2, AND LL1 scales. The back of the slide has T, Sec T and ST, Cos and S, and C scales. The LL/1, LL/2, LL/3, T, and Sec T scales are numbered in red. All the other scales are navy.
The rule fits into a black Fabrikoid case with a leather flap (stamped POST). The case could be hung from the user's belt, and it is labeled: W. K. KRUTZ. The case is stored in a red, white, and black cardboard box, along with a guarantee from Post and a ruler-sized white plastic set of conversion tables, copyrighted in 1950 by the Eugene Dietzgen Co., another prominent slide rule manufacturer. The rule also arrived with an instruction booklet, 1978.0800.02.
References: Jiro Hemmi, "Slide-Rule" (U.S. Patent 1,329,902 issued February 3, 1920); Walter Shawlee II, Ted Hume, and Paul Ross, "The Post Slide Rule Archive," Sphere Research Corporation, http://www.sphere.bc.ca/test/post.html; Bob Otnes, "Notes on Frederick Post Slide Rules," Journal of the Oughtred Society 7, no. 1 (1998): 7–10; Paul Ross and Ted Hume, "Slide Rules of the Frederick Post Company," Journal of the Oughtred Society 9, no. 2 (2000): 37–46; Ted Hume, "The Popular Post Versalog Slide Rule," Journal of the Oughtred Society 15, no. 1 (2006): 53–55; William Lise, "Japanese Slide Rules," 19 August 2004, accessed via Internet Archive Wayback Machine; E. I. Fiesenheiser, The Versalog Slide Rule: An Instruction Manual (Chicago: The Frederick Post Company, 1951).
Location
Currently not on view
date made
1959
maker
SUN HEMMI JAPAN CF
inventor
Frederick Post Co.
ID Number
1978.0800.01
catalog number
336682
accession number
1978.0800

Pickett 101-C Circular Slide Rule

This yellow aluminum circular slide rule has three clear plastic indicators, one blank. The other indicator on the front is marked in red to denote the C, CI, A, AF, L, FA, LL2, LL1, DS, DT, and M scales.
Description
This yellow aluminum circular slide rule has three clear plastic indicators, one blank. The other indicator on the front is marked in red to denote the C, CI, A, AF, L, FA, LL2, LL1, DS, DT, and M scales. The indicator on the back is marked in red to denote the C, S,ST, and T scales. A ring of numbers under the scales on the back permits conversions from fractions to decimals.
The center of the front is marked: CIRCULAR SLIDE RULE – dial rule (/) PICKETT. The center of the back is marked: dial rule (/) NO 101-C. A triangular Pickett logo, of the form used between 1950 and 1958, appears at the bottom of the center; CHICAGO is printed below the logo.
Pickett & Eckel, a slide rule manufacturer based in Chicago and Alhambra, Calif., distributed a small booklet with this instrument, one of the few circular slide rules sold by the company and possibly the only circular model it manufactured. Maurice L. Hartung, a University of Chicago mathematics professor associated with the company, wrote the instruction manual (1981.0922.13). The booklet is copyrighted 1957, and the logo on this copy was used by the company between 1958 and 1962. Thus, this slide rule dates to about 1958.
References: Rodger Shepherd, "Pickett Metal Slide Rules," Journal of the Oughtred Society 1, no. 1 (1992): 5–8; Walter Shawlee, "Information About Pickett Slide Rules," Sphere Research Slide Rule Site, http://www.sphere.bc.ca/test/pickett.html.
Location
Currently not on view
date made
ca 1958
maker
Pickett & Eckel, Incorporated
ID Number
1981.0922.12
catalog number
1981.0922.12
accession number
1981.0922

Keuffel & Esser 4092 Log Log Duplex Slide Rule

This ten-inch mahogany duplex slide rule is faced with yellowed white celluloid and held together with corroded L-shaped end pieces. On one side, the base has A and D scales, with B, S, and C scales on the slide. The left end of the slide is marked in red: < 4092 >.
Description
This ten-inch mahogany duplex slide rule is faced with yellowed white celluloid and held together with corroded L-shaped end pieces. On one side, the base has A and D scales, with B, S, and C scales on the slide. The left end of the slide is marked in red: < 4092 >. The bottom of the base is marked in red: KEUFFEL & ESSER CO. N.Y.; PAT. JUNE 5. '00 DEC. 22. '08. On the other side, the base has LL1, LL2, LL3, D, and L scales, with C, T, and CI scales on the base. The indicator is frameless glass with plastic edges fastened with screws. One edge is marked: K&E.CO.N.Y. (/) PAT.8.17.15.
Keuffel & Esser of New York offered model 4092 from about 1909 to 1921. The frameless glass indicator was introduced in 1915. The rule sold for $8.00 from 1909 through 1915 and for $12.50 in 1921. This example fits in a cardboard case covered with black leather and marked: KEUFFEL & ESSER Co. (/) LOG. LOG. (/) SLIDE RULE. For instructions, see 1981.0993.02. Later examples of K&E Log Log slide rules in the collections include 1984.1068.02, MA.318479, 1990.0687.01, 1986.0790.03, and 1987.0085.01.
The donor, William J. Ellenberger (1908–2008), studied electrical and mechanical engineering at The George Washington University between 1925 and 1934. He then worked for the Potomac Electric Power Company and the National Bureau of Standards. During World War II, he served in the U.S. Army Signal Corps. He was a civilian construction management engineer for the army from 1954 to 1968, when he became a private consultant.
References: Catalogue of Keuffel & Esser Co., 33rd ed. (New York, 1909), 312; Catalogue of Keuffel & Esser Co., 35th ed. (New York, 1915), 304; Catalogue of Keuffel & Esser Co., 36th ed. (New York, 1921), 240; "The GW Engineering Hall of Fame 2006 Inductees," http://www.weas.gwu.edu/ifaf/hall_of_fame_inductees_2006.php.
Location
Currently not on view
date made
1915-1921
maker
Keuffel & Esser Co.
ID Number
1981.0933.01
catalog number
1981.0933.01
accession number
1981.0933

Routledge's Engineer Linear Slide Rule

This is a two-foot, two-fold boxwood rule with a brass hinge and endpieces. Half of one side is a slide rule with A and D scales on the base and B and C scales on the slide.
Description
This is a two-foot, two-fold boxwood rule with a brass hinge and endpieces. Half of one side is a slide rule with A and D scales on the base and B and C scales on the slide. As with MA.306697.01, the C scale is the same as the A and B scales (the square of the D scale), instead of the same as the D scale, as on modern Mannheim slide rules. Below the D scale is marked: SQUARE CYLINDER GLOBE (3 times) ROUTLEDGE'S ENGINEER.
The first three marks form headings for the tables on the other half of this side when the instrument is folded. The tables give conversion factors from the volumes of geometric solids to units of volume, in both the "old" and imperial systems; conversion factors from the volumes of geometric solids to the weights in pounds of various substances; the areas of polygons from 5 to 12 sides; the gauge points of a circle; and gauge points for pumping engines, to find the diameters of steam cylinders that will work pumps of specified diameter at 7 pounds per square inch.
The other side has a scale of 24 inches along one edge, divided to sixteenths of an inch for 9 inches and to eighths of an inch for the rest of the scale. There are also scales for making scale drawings that are 1, 3/4, 1/2, and 1/4 inches to the foot. This side is marked: T. ASTON THE ORIGINAL MAKER WARRANTED. One outside edge has scales for 10 and 12 parts to the inch; the other outside edge divides one foot into 100 parts.
This form of slide rule was invented by Joshua Routledge, a seller of iron goods, in 1808 or 1809. He discussed it in the 1813 (4th) edition of Instructions for the Engineer's Improved Sliding Rule. According to Gloria Clifton, there were two rule makers named Thomas Aston, presumably a father and son, who were in business at various addresses in Birmingham, England, from 1818 to 1862. The references to pre-imperial system units of measure suggest the rule might have been made shortly after the imperial system was adopted in 1824. This instrument was found in the home of Grace Speer, granddaughter of Alfred Speer (1823–1910), an inventor and wine merchant in Passaic, N.J.
References: John V. Knott, "Joshua Routledge 177[3]–1829," Journal of the Oughtred Society 4, no. 2 (1995): 25; Philip E. Stanley, "Carpenters' and Engineers' Slide Rules: Routledges' Rule," Chronicle of the Early American Industries Association 37, no. 2 (1984): 25–27; Gloria Clifton, Directory of British Scientific Instrument Makers (London: National Maritime Museum, 1995), 11–12; accession file.
Location
Currently not on view
date made
1824-1862
maker
Aston, T.
ID Number
1981.0934.01
catalog number
1981.0934.01
accession number
1981.0934

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

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. .
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.
Location
Currently not on view
date made
1955-1962
date received
1986
maker
Keuffel & Esser Co.
ID Number
1986.0790.03
accession number
1986.0790
catalog number
1986.0790.03

Pickett N500-ES Log Log Duplex Slide Rule

This duplex aluminum linear slide rule is coated in yellow ("eye saver") plastic and is held together with stamped aluminum contoured posts. The nylon cursor has a convex lens.
Description
This duplex aluminum linear slide rule is coated in yellow ("eye saver") plastic and is held together with stamped aluminum contoured posts. The nylon cursor has a convex lens. The front of the base has +LL1, -LL1, A, D, DI, and K scales, with B, T, ST, S, and C scales on the front of the slide. The left end of the slide is marked: MODEL (/) N-500-ES (/) HI LOG/LOG. The right end of the slide has the Pickett logo used between 1964 and 1975 ("PickETT" with a triangle dotting the i) and MADE IN U.S.A.
The back of the base has +LL2, -LL2, DF, D, +LL3, and -LL3 scales, with CF, CIF, L, CI, and C scales on the back of the slide. Both ends of the slide are marked with the Pickett logo, with ALL METAL (/) SLIDE RULES on the left end and ©1962 on the right end.
There is a black leather case lined with black plastic and marked below the slot for the flap with the Pickett logo in gold. The case has no belt loop. The case fits into a white, green, and black cardboard box. Compare to the box collected with 1995.0126.02. The bottom of this box has a flap marked: PickETT (/) WORLD'S MOST ACCURATE (/) SLIDE RULES. A blue and white sticker on the flap describes the slide rule's features: N500 (/) HI-LOG SPEED RULE (/) THE SUPERIOR TRIG/LOG LOG RULE FOR ESSEN- (/) TIAL ENGINEERING AND TECHNICAL NEEDS (/) All Metal construction for highest accuracy and lifetime (/) performance (/) 22 Key Scales with a comprehensive 60-inch log range (/) With Carrying Case and complete instruction manual (/) Lifetime Guarantee.
The guarantee, with a registration card, is in the bottom of the box, along with the plastic bag that originally contained the slide rule inside the case. The registration card indicates that this example's serial number is A103202 and that the company's headquarters were in Santa Barbara, Calif. The company moved to Santa Barbara in 1964. Along with the logo, this suggests the slide rule was made in the mid-to-late 1960s. Students typically purchased this model in college and continued to use it in their careers.
Reference: International Slide Rule Museum, "Pickett," http://sliderulemuseum.com/Pickett.htm.
Location
Currently not on view
date made
after 1964
maker
Pickett Industries
ID Number
1999.0096.01
catalog number
1999.0096.01
accession number
1999.0096

Pickett N4-ES Vector-Type Log Log Duplex Slide Rule

This aluminum ten-inch linear duplex slide rule is coated in Pickett's "Eye Saver" yellow plastic. The flat nylon indicator is screwed within a white plastic frame.
Description
This aluminum ten-inch linear duplex slide rule is coated in Pickett's "Eye Saver" yellow plastic. The flat nylon indicator is screwed within a white plastic frame. The front top of the base has three extended cube root scales (one for numbers with 1, 4, 7, 10, or more digits before the decimal point; one for numbers with 2, 5, 8, 11, or more digits; and one for numbers with 3, 6, 9, 12, or more digits) and a DF scale. The front bottom of the base has D, DI, and square root scales. The top square root scale gives roots of numbers on the D scale with an odd number of digits before the decimal point; the lower square root scale gives roots of numbers with an even number of digits. The front of the slide has CF, CIF, double T, ST, S, CI, and C scales.
The left end of the slide is marked: MODEL N4-ES (/) Vector-Type LOG LOG (/) DUAL-BASE SPEED RULE. The right end has "Pickett" in script on a triangle with a dot at one point. MADE IN U.S.A. appears beneath the logo. This form of logo was in use from 1958 to 1962. The style of the grooved stamped aluminum posts is also consisted with this timeframe.
The top back of the base has LL1, LL2, and DF/M scales. D, LL3, and LL4 scales are on the bottom of the base. The back of the slide has CF/M, TH, SH, Ln, L, CI, and C scales. The back of the slide is marked at the left end: COPYRIGHT 1959© (/) PATENT APPLIED FOR. The right end is marked: PICKETT (/) ALL METAL (/) SLIDE RULES (/) PICKETT & ECKEL INC. (/) CHICAGO ILL. U.S.A. The mention on the instrument of a patent application may refer to a patent for a case issued to John W. Pickett in 1960. Pickett was the son of company founder Ross C. Pickett and served as president of the firm from 1957 to 1967.
The slide rule is in a red-brown leather case lined in white plastic. The triangular Pickett logo is stamped in gold on the front of the case, and a metal ring on the back is for a leather strap (no longer with the instrument) that can be hung around a belt loop. See 1980.0097.04 for instructions.
The donor, engineer Edgar F. Peebles, obtained this slide rule free of charge as a replacement when the numbers came off the slide rule he had used in college. He first used it from 1959 to 1965 in the satellite control facility of the Air Force at Sunnyvale, Calif. He then used it as a down range representative for Lockheed Missiles and Space Company from 1965 to 1968 in tests of the Polaris missile. Finally, from 1968 to 1969 he used the slide rule in the checkout area of the test Polaris missile manufacturing plant in Sunnydale.
References: Rodger Shepherd, "Pickett's 'Eye Saver Yellow,'" Journal of the Oughtred Society 1, no. 1 (1992): 18; International Slide Rule Museum, "Pickett All-Metal Slide Rules," http://sliderulemuseum.com/SR_Dates.htm#Pickett; Maurice L. Hartung, How to Use . . . Pickett Dual Base Log Log Slide Rules (Chicago: Pickett & Eckel, Inc., 1953), http://sliderulemuseum.com/Manuals/M103_Pickett_HowToUseDualBase_1953.pdf; John W. Pickett, "Slide Rule Case" (U.S. Patent D187,632 issued April 5, 1960); accession file.
Location
Currently not on view
date made
ca 1959
maker
Pickett & Eckel, Incorporated
ID Number
2000.0203.01
accession number
2000.0203
catalog number
2000.0203.01

Dietzgen 1734 Decimal Trig Log Log Duplex Slide Rule

Relatively late in its history of making and selling slide rules, the Eugene Dietzgen Co. of Chicago began developing products that competed with the high-end slide rule lines manufactured by Keuffel & Esser (namely, model 4081) and Post (the Versalog).
Description
Relatively late in its history of making and selling slide rules, the Eugene Dietzgen Co. of Chicago began developing products that competed with the high-end slide rule lines manufactured by Keuffel & Esser (namely, model 4081) and Post (the Versalog). This two-sided, ten-inch wooden slide rule is coated with white plastic and has metal endpieces. On one side the base has LL02, LL03, DF, D, LL3, and LL2 scales, with CF, CIF, L, CI, and C scales on the slide. The top of the base is marked: DIETZGEN MICROGLIDE TM DECIMAL TRIG TYPE LOG LOG CAT. NO. 1734.
On the other side, the base has LL01, K, A, D, DI, and LL1 scales, with B, T < 45°, T > 45°, ST, and S scales on the slide. The top of the base is marked: EUGENE DIETZGEN CO. PATS. 2,170,144 2,285,722 PAT'S PEND. MADE IN U.S.A. 020038. On both sides the right end of the rule has formulas indicating the functions represented by the scales. The glass indicator has a metal and black plastic frame; both edges are marked: DIETZGEN.
The rule fits in a black leather case with a metal clasp. A Dietzgen logo is on the flap—the letter D inside the letter E inside the letters Co. In 1959 Dietzgen introduced the Microglide line of slide rules, which featured Teflon-lined grooves on the base so that the slide moved more smoothly. According to Ian Lodge's estimated production figures, the serial number suggests a manufacture date for this object of 1962.
Dietzgen ceased the production of slide rules around 1972. The arrangement of scales corresponds to those depicted in a 1960 instruction manual for the "Dietzgen Decimal Trig Type Log Log Slide Rule," although the "Microglide" trademark is not mentioned. See 1986.0790.01 for information on the patents mentioned on the instrument. The indicator is Dietzgen's "framed full vision" type and is covered by U.S. Patent 2,634,912, issued to Clarence P. Davey on April 14, 1953.
The donor, Ed Severino, began his career as an engineer with General Electric Company in Schenectady, N.Y. After eight years, he left to teach mathematics and science at Mont [sic] Pleasant High School in Schenectady, where he became head of the Technical Department. The slide rule is of the type trainees used in the late 1970s and early 1980s, when Severino was director of his high school's General Electric Apprentice Training Educational Program.
References: Rodger Shepherd, "Some Distinctive Features of Dietzgen Slide Rules," Journal of the Oughtred Society 5, no. 2 (1996): 42–45; Robert K. Otnes, "Dietzgen Patents, Runners, and Log-Log Scales," Journal of the Oughtred Society 5, no. 2 (1996): 45–48; Ian Lodge, "Estimating Production Dates for Dietzgen Micromatic and Microglide Log Log Duplex Slide Rules," Journal of the Oughtred Society 21, no. 1 (2012): 26–32; Bruce Babcock, "Dietzgen Catalog Matrix," Journal of the Oughtred Society 5, no. 2 (1996), http://sliderulemuseum.com/Manuals/Dietzgen_CatalogMatrix_BruceBabcock1996_chart.jpg; Ovid W. Eshbach and H. Loren Thompson, Self-teaching Instruction Manual: Dietzgen Decimal Trig Type Log Log Slide Rule (Chicago: Eugene Dietzgen Co., 1960), http://sliderulemuseum.com/Manuals/Dietzgen_1734_Manual.pdf; "Your Dietzgen Microglide Slide Rule: Instructions for Care and Adjustment" (Chicago, n.d.), http://sliderulemuseum.com/SR_Library_Dietzgen.htm.
Location
Currently not on view
date made
ca 1962
maker
Eugene Dietzgen Company
ID Number
2006.0230.01
accession number
2006.0230
catalog number
2006.0230.01

Ricoh Duplex Slide Rule Sold by Staedtler-Mars (944-24)

Numerous slide rule manufacturers also sold rules made by other companies.
Description
Numerous slide rule manufacturers also sold rules made by other companies. For instance, the German pencil-manufacturer Staedtler, which used the trade name Mars for slide rules, marketed this ten-inch bamboo rule coated with white plastic and held together with metal L-shaped endpieces. Staedtler's own rules had distinctive light blue slides, but this rule is entirely white. It was made as model 151 between about 1960 and 1972 by the Japanese firm known as San-Ai Measuring Instruments and then as Ricoh Measuring Instruments. Several companies besides Staedtler sold these rules, including Lutz.
On one side, the base has LL/1, LL/2, LL/3, DF, D, LL3, LL2, and LL1 scales, with CF, CIF, CI, and C scales on the slide. The right end of each scale identifies the meaning of the letters, i.e., the C and D scales are marked with an x. The right end of the slide has the company logo of a Greek soldier's head and is marked: STAEDTLER (/) MARS (/) 944 24. On the other side, the base has LL/0, L, K, A, D, DI, P, and LL0 scales, with B, S, ST, T, and C scales on the slide. The indicator is clear plastic with white plastic edges. The bottom edge of the rule is marked: JAPAN.
The rule fits in a brown leather case with a loop for attaching to a belt. The flap is marked: STAEDTLER (/) MARS. The back bottom of the case is marked: JAPAN. A blue and white cardboard box is marked on the end: STAEDTLER MARS (/) 1 BAMBOO SLIDE RULE 944 24 (/) Duplex Log Log 10". See 2009.0019.02.01 for instructions. Compare to 1986.0790.04.
The mathematician and theoretical computer scientist Harley Flanders received this instrument as a gift, but he never used it.
References: "A Modern Brand Rich in Tradition," Staedtler, http://www.staedtler.com/brand_with_tradition_gb.Staedtler?ActiveID=3049; David A. Davis, "Relay/Ricoh Archive," http://www.oocities.org/usra482b/page3.html; Peter M. Hopp, Slide Rules: Their History, Models, and Makers (Mendham, N.J.: Astragal Press, 1999), 213.
Location
Currently not on view
date made
1960-1972
maker
Ricoh Measuring Instruments
ID Number
2009.0019.02
accession number
2009.0019
catalog number
2009.0019.02

Hawthorn's Mechanics' Slide Rule

From the late 18th to the mid-19th centuries, British engineers began to use slide rules. This ivory and silver instrument is a four-fold engineer's rule that unfolds to a length of 24 inches.
Description
From the late 18th to the mid-19th centuries, British engineers began to use slide rules. This ivory and silver instrument is a four-fold engineer's rule that unfolds to a length of 24 inches. On half of one side is a slide rule with A and D scales on the base and B and C scales on the slide. The A and D scales seem to run continuously, although the slide only moves on the second six inches of the rule.
The words IRON and ROPE appear several times along the edge of the A scale. Along the edge of the D scale is marked: DESCRIPTION SQUARE CYL[I]ND[ER] GLOBE SQUARE CYL[I]ND[ER] WEIGHT STRAIN WORK INCLIN[E] POLYGON SIDE GOVERNORS H[ORSE]P[OWER] ENGIN[E]S STE[A]M TEM[PERATURE]. When the rule is folded, these markings correspond to the tables on the other half of the instrument.
The other half of this side has a table of gauge points for the A scale. Instructions printed on the rule suggest that calculations on the slide rule were intended to be made with calipers. Additional tables and instructions for working with ropes and chains are on this half, which is marked: IMPROVED & ARRANG[E]D (/) BY RT HAWTHORN (/) CIVIL ENGINEER (/) NEWCASTLE TYNE.
The other side has a scale of 24 inches divided to eighths of an inch along the edge. The metal joint has a protractor divided in increments of 5 degrees and marked by tens from 0 to 180. When the instrument is folded around the joint, there are tables for the extreme strain possible in bars and beams of various substances and for equivalent measures. The joint is marked: G. R. STEPHENSON (/) ENGINEER (/) Adam Pensom.
In 1832 civil engineer Robert Hawthorn (1796–1867) designed a new form of slide rule for manufacturing locomotives and other engines. In 1859 dealers sold the rule for 5 shillings and 6 pence. The names on the joint may refer to the British civil engineer George Robert Stephenson (1819–1905), nephew to the engineer George Stephenson (1781–1848), who sought mechanical advice from Hawthorn's father, and to Adam Pensom (b. 1824), who was a retired gas engineer living in London, according to the 1881 British census. The Smithsonian acquired this object in 1973.
References: Robert Hawthorn, Instructions for the Use of the Mechanics' Sliding Rule (Newcastle-upon-Tyne, 1841), available online at http://www.physics.uq.edu.au/physics_museum/hawthorne/; "Mr. Robert Hawthorn," Minutes of the Proceedings of the Institution of Civil Engineers 27 (1867–1868): 590–592; advertisement by John Archbutt, The Mechanics' Magazine, n.s., 1, no. 10 (March 4, 1859): 486; Peter M. Hopp, Joint Slide Rules (Jeremy Mills Publishing: Lindley, Huddersfield, West Yorkshire, 2009).
Location
Currently not on view
date made
after 1832
maker
Hawthorn, Robert
ID Number
MA.306697.01
accession number
306697
catalog number
306697.01

Keuffel & Esser 4090-3 Log Log Trig Duplex Slide Rule

This ten-inch mahogany duplex slide rule is coated all around with white celluloid and held together with L-shaped metal end pieces. The front of the base has LL0, A, T, S2, and S1 scales, with B, K, and CI scales on the slide.
Description
This ten-inch mahogany duplex slide rule is coated all around with white celluloid and held together with L-shaped metal end pieces. The front of the base has LL0, A, T, S2, and S1 scales, with B, K, and CI scales on the slide. The LL0 scale is a log log scale of decimal quantities. The A and B scales are identical, divided logarithmically from 1 to 10 twice in the length of the scale in the usual manner. The K scale is also divided logarithmically, but three times in the length of the scale, for use in finding cubes and cube roots. The CI scale is divided logarithmically from 1 to 10 the length of the scale, going in the opposite direction from the A and K scales. The T scale is a scale of tangents and cotangents, doubly numbered with angles given in degrees and minutes. The S1 and S2 scales are scales of sines and cosines, doubly numbered. The top of the base is marked in red: KEUFFEL & ESSER CO.N.Y.; PAT. APRIL 1.'24 OTHER PAT. PENDING; MADE IN U.S.A. The left end of the slide and the front of the rule are marked with a serial number: 448333.
The back of the base has L, LL1, DF, D, LL3, and LL2 scales, with CF, CIF, and C scales on the slide. The right end of the slide is marked in red: < 4090-3 >. A glass indicator has white plastic edges held together with metal screws. One edge is marked: KEUFFEL & ESSER CO.N.Y. The other is marked: PATENTED AUG.17.15. (/) OTHER PAT. PENDING.
Keuffel & Esser advertised model 4090-3 from 1933 to 1936. However, the combination of scales on this example was only issued in 1933, when the rule sold for $10.00. The serial number is consistent with this date. In 1937, model 4090-3 was replaced by model 4080-3.
References: Adolf W. Keuffel, "Log Log Duplex Slide Rule" (U.S. Patent 1,488,686 issued April 1, 1924); K&E Slide Rules and Calculating Instruments (New York, 1933), 10–11; Catalogue of Keuffel & Esser Co., 38th ed. (New York, 1936), 316–317; Dieter von Jezierski, Slide Rules: A Journey Through Three Centuries, trans. Rodger Shepherd (Mendham, N.J.: Astragal Press, 2000), 71–75; Clark McCoy, ed., "Collection of Pages from K&E Catalogs for the 4090-3 & 4091-3 Family of Slide Rules," http://www.mccoys-kecatalogs.com/KEModels/ke4091-3family.htm.
Location
Currently not on view
date made
1933
maker
Keuffel & Esser Co.
ID Number
MA.318479
accession number
235479
catalog number
318479

Scofield-Thacher Engineer's Slide Rule

This 22-inch, two-sided wooden slide rule has scales that are printed on paper but not engine-divided. On the front of the base, logarithmic scales are labeled B and C on the left and D and D on the right.
Description
This 22-inch, two-sided wooden slide rule has scales that are printed on paper but not engine-divided. On the front of the base, logarithmic scales are labeled B and C on the left and D and D on the right. The C scale is the inverse of the B scale and is also labeled RECIPROCALS. The first D scale runs from 1 to 3.16, and the second D scale runs from 3.16 to 10. These scales are labeled ROOTS.
Four identical scales are on the slide, all logarithmically divided from 1 to 10 and labeled A. Two of the scales are at the left end of the slide, and two are at the right end of the slide. These scales are also identical to the B scale. Written in pencil on the back of the slide and underneath the slide is the number 1103. The bottom of the base is marked: Patented July 2, 1901.
The back of the base has scales divided logarithmically from 1 to 10 and from 3.16 to 10 to 3.16. These scales are both labeled F at both ends. The slide also has scales divided logarithmically from 1 to 10 and from 3.16 to 10 to 3.16. These scales are both labeled E at both ends. Faded red numbers from 1 to 4 also appear on all four scales. Written in pencil on the back of the slide and underneath the slide is: 1102. The bottom of the base is marked: Patented July 2, 1901.
The top edge of the rule is marked: THE ENGINEERS (/) SLIDE RULE. It is also marked: From E. M. Scofield, Bridge Engineer. (/) Sta. A, – Youngstown, – Ohio. (/) Rule sent prepaid on receipt of price. (/) Factory, – Youngstown, Ohio. The paper pasted on this edge also has the formula ex/f, a description of how to solve this formula with the instrument, and tables of equivalents. The bottom edge of the rule gives seventeen more formulas and instructions. It is marked: DIRECTIONS FOR SCALES A • B • C & D (/) FOR "Op." READ "OPPOSITE" (/) FOR "—" READ "ON SCALE" (/) FOR "Ans." READ "FIND ANSWER" (/) FOR LAST SIX PROBLEMS REVERSE SLIDE.
Edson Mason Scofield (1867–1939) developed this rule in 1891 while he worked for Edwin Thacher (inventor of the cylindrical slide rule bearing his name; see, for example, MA.312866). Thacher applied for a patent on the design in 1900 and assigned a half-interest to Scofield when the patent was issued in 1901. According to the instrument, Scofield may have distributed the rule himself.
It was also sold by Eugene Dietzgen Company of Chicago from about 1901 through at least 1931. The price for model 1787 ranged from $5.00 to $7.00. By 1926 Dietzgen marked the rule with its company name. Meanwhile, Scofield went on to become president and chief engineer of the National Bridge Company of Pittsburgh in 1901. From 1903 he and his brother, Glenn M. Scofield, operated the Scofield Engineering Company in Philadelphia, New York City, and Los Angeles. This example belonged to Robert A. Cummings, a civil engineer who was the father of the donor. Compare to MA.333710.
References: Edwin Thacher, "Slide Rule" (U.S. Patent 677,817 issued July 2, 1901); Catalogue & Price List of Eugene Dietzgen Co., 7th ed. (Chicago, 1904), 173; Catalog of Eugene Dietzgen Co., 12th ed. (Chicago, 1926), 177; Conrad Schure, "The Scofield-Thacher Slide Rule," Journal of the Oughtred Society 3, no. 1 (1994): 20–25; Peter M. Hopp, Slide Rules: Their History, Models, and Makers (Mendham, N.J.: Astragal Press, 1999), 161.
Location
Currently not on view
date made
1901-1926
maker
Scofield, E. M.
ID Number
MA.325990
catalog number
325990
accession number
258733

Scofield-Thacher Engineer's Slide Rule

The scales on this 22-inch, two-sided wooden slide rule are printed on paper. The front has two scales on the left end of the base labeled B and C and two scales labeled A on the left end of the slide. These scales run half the length of the instrument.
Description
The scales on this 22-inch, two-sided wooden slide rule are printed on paper. The front has two scales on the left end of the base labeled B and C and two scales labeled A on the left end of the slide. These scales run half the length of the instrument. The B and two A scales are identical, divided logarithmically from left to right and running from 1 to 10. The C scale is divided logarithmically from right to left and runs from 10 to 1. It is labeled RECIPROCALS.
The right end of the base has two D scales, both labeled ROOTS, with two additional A scales on the right end of the slide. The A scales are divided logarithmically from left to right and run from 1 to 10. The top D scale runs from 1 to 3.16 and shows square roots of the numbers on the A scale below it. The bottom D scale runs from 3.16 to 10 and shows square roots of the numbers on the A scale above it, between 10 and 100. Written in pencil on the back of the slide and underneath the slide is the number 1096.
The back of the rule contains two scales on the base labeled F and two scales on the slide labeled E. The top F scale runs the length of the scale and is divided logarithmically from 1 to 10. The sections between 1 and 2, between 2 and 3, between 3 and 4, and between 4 and 5 are subdivided. The lower F scale is similarly divided, but starts from the center of the rule (running from the square root of 10, or 3.16, to 10 and then from 1 to the square root of 10). The E scales are identical to the adjacent F scales. Written in pencil on the back of the slide and underneath the slide is the number 1097.
The bottom of the base on both sides is marked: Patented July 2, 1901. The top edge of the rule is marked: THE ENGINEERS (/) SLIDE RULE. It is also marked: From E. M. Scofield, Bridge Engineer. (/) Sta. A, – Youngstown, – Ohio. (/) Rule sent prepaid on receipt of price. (/) Factory, – Youngstown, Ohio. The paper pasted on this edge also has the formula ex/f, a description of how to solve this formula with the instrument, and tables of equivalents. The bottom edge of the rule gives seventeen more formulas and instructions. It is marked: DIRECTIONS FOR SCALES A • B • C & D (/) FOR "Op." READ "OPPOSITE" (/) FOR "—" READ "ON SCALE" (/) FOR "Ans." READ "FIND ANSWER" (/) FOR LAST SIX PROBLEMS REVERSE SLIDE.
Edson Mason Scofield (1867–1939) developed this rule in 1891, while he worked for Edwin Thacher (inventor of the cylindrical slide rule bearing his name; see, for example, MA.312866). Thacher applied for a patent on the design in 1900 and assigned a half-interest to Scofield when the patent was issued in 1901. According to the instrument, Scofield may have distributed the rule himself. It was also sold by Eugene Dietzgen Company of Chicago from about 1901 through at least 1931. The price for model 1787 ranged from $5.00 to $7.00. By 1926, Dietzgen marked the rule with its company name. This instrument is identical to MA.325990.
John N. Welsh (1904–1999), the donor of this slide rule, was a chemical engineer who obtained his B.S. from the Carnegie Institute of Technology in 1925. He was associated with Hall Laboratories, Inc. of Pittsburgh (later CALGON) from 1939 through at least 1968. By 1972, when this slide rule was briefly placed on exhibit, Welsh was living in Florida.
References: Edwin Thacher, "Slide Rule" (U.S. Patent 677,817 issued July 2, 1901); Catalogue & Price List of Eugene Dietzgen Co., 7th ed. (Chicago, 1904), 173; Catalog of Eugene Dietzgen Co., 12th ed. (Chicago, 1926), 177; Conrad Schure, "The Scofield-Thacher Slide Rule," Journal of the Oughtred Society 3, no. 1 (1994): 20–25; Peter M. Hopp, Slide Rules: Their History, Models, and Makers (Mendham, N.J.: Astragal Press, 1999), 161; Who's Who in Engineering (New York and West Palm Beach: Lewis Historical Publishing Co., 1964), 1996.
Location
Currently not on view
date made
1901-1926
maker
Scofield, E. M.
ID Number
MA.333710
catalog number
333710
accession number
300658

Keuffel & Esser 4083-5 Log Log Vector Duplex Slide Rule

This 20-inch mahogany duplex slide rule is coated with white celluloid and held together with metal end pieces. On one side, the base has LL02, LL03, DF, D, LL3, and LL2 scales, with CF, CIF, CI, and C scales on the slide.
Description
This 20-inch mahogany duplex slide rule is coated with white celluloid and held together with metal end pieces. On one side, the base has LL02, LL03, DF, D, LL3, and LL2 scales, 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, the base has Sh1, Sh2, Th, A, D, DI, LL01, and LL1 scales, with B, T, SRT, and S scales on the slide. The first three scales are hypobolic scales. The trigonometric scales are divided into degrees and into decimals. The left end of the slide has a serial number: 640023. The left ends of both parts of the base are marked: 023. A glass indicator has plastic edges and metal screws. Compare to MA.318481
The top edge of the rule is marked: PATS. PEND. MADE IN U.S.A. 4083-5 LOG LOG DUPLEX VECTOR ® COPYRIGHT 1947 BY KEUFFEL & ESSER CO. PATS. 2,500,460 2,168,056 2,170,144 2,285,722 2,422,649. See 2007.0181.01 for a description of these patents. There is a green leather case with metal inlays on the holder for the flap. One of the inlays is marked: PAT. 2,000,337. The flap is marked: K + E. Adolf W. Keuffel applied to patent his method for securing a slide rule case on November 1, 1932, and received the patent on May 7, 1935.
Keuffel & Esser of New York used this set of scales on this model number from 1955 to 1962. The serial number is consistent with a date later in this time frame. The rule sold with the leather case for $56.50 in the 1950s.
References: Adolf W. Keuffel, "Slide Rule Case" (U.S. Patent 2,000,337 issued May 7, 1935); K + E Catalog, 42nd ed. (New York: Keuffel & Esser Co., 1954), 280–281; Keuffel & Esser Co., "Price List Applying to the 42nd Edition Catalog" (New York, June 1, 1956), 43; Clark McCoy, "Collection of Pages from K&E Catalogs for the 4083-3 Family of Slide Rules," http://www.mccoys-kecatalogs.com/KEModels/ke4083-3family.htm; Ed Chamberlain, "Estimating K&E Slide Rule Dates," 27 December 2000, http://www.sphere.bc.ca/test/ke/320-k+e_date2.jpg.
Location
Currently not on view
date made
1955-1962
maker
Keuffel & Esser Co.
ID Number
MA.335483
accession number
321673
catalog number
335483

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