Index by Material

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

Slide rules were sometimes distinctive by the materials from which they were made. Early rules were often made from boxwood and other woods. By the late 19th century, German manufacturers and Keuffel & Esser of New York City had not only switched to the more uniform and durable mahogany but were also coating the wood with early forms of plastic (celluloid). Around the turn of the 20th century, Japanese firms used bamboo, which did not expand and shrink as much as wood, thus reducing errors in the results of calculations. Later, Pickett slide rules were notable for their aluminum construction and proprietary yellow color. Although the rules tended to be less affordable and popular than wooden rules, manufacturers have used brass and other metals throughout the history of slide rules. Plastic and paper became increasingly widespread for inexpensive rules in the 20th century.

AluminumChromiumMetalSterling Silver
BambooIvoryPaperWood
BoxwoodMagnesiumPlasticYew
BrassMahogany  
Search term: *:* Date: 1880s Clear All

Darling, Brown & Sharpe Astronomical Linear Slide Rule

This large mahogany linear astronomical slide rule is covered with strips of German silver. There are two slides, each of which have scales on both sides. Each slide has a knob near one end for moving it; these may be unscrewed and attached on the reverse side.
Description
This large mahogany linear astronomical slide rule is covered with strips of German silver. There are two slides, each of which have scales on both sides. Each slide has a knob near one end for moving it; these may be unscrewed and attached on the reverse side. One slide is marked COLLIMATION on one side and AZIMUTH on the other. The other slide is marked LEVEL AZIMUTH on one side and REFRACTION on the other. The base has four identical, unlabeled logarithmic scales, each of which runs from 1 to 10 twice (with a bit more at each end).
On the center portion of the base, the instrument is marked Darling Brown & Sharpe Providence R.I. Darling, Brown & Sharpe did business under that name from 1866 to 1892. For additional company history, see 1977.0460.01. According to records of the United States Naval Observatory, this slide rule was purchased for $154.00 in December 1887. Few slide rules specifically for astronomy survive, so these large and expensive objects were probably not widely used. Compare to two late 19th-century rules held by the Powerhouse Museum, http://www.powerhousemuseum.com/collection/database/?irn=233017.
Reference: Ledger of Instruments Purchased by the U.S. Naval Observatory, ca. 1845–1906, United States Naval Observatory, Washington, D.C.
Location
Currently not on view
date made
1887
patentee
Darling, Samuel
maker
Brown & Sharpe Manufacturing Company
ID Number
1987.0693.01
catalog number
328994
accession number
1987.0693

Keuffel & Esser 1740 Thacher Cylindrical Slide Rule

This rule has a cylindrical hollow brass drum, which is covered with paper printed with 40 A scales. The first A scale runs from 100 to 112; the fortieth runs from 946 to 100 to 105. The paper is also printed in italics on the right side: Patented by Edwin Thatcher [sic], C.E.
Description
This rule has a cylindrical hollow brass drum, which is covered with paper printed with 40 A scales. The first A scale runs from 100 to 112; the fortieth runs from 946 to 100 to 105. The paper is also printed in italics on the right side: Patented by Edwin Thatcher [sic], C.E. Nov. 1st 1881. Divided by W. F. Stanley, London, 1882. A wooden handle is attached to each end of the drum, and the drum slides in both directions.
The drum fits inside an open rotating frame to which 20 brass slats are fastened. The slats are lined with cloth and covered with paper. The paper on each slat is printed with two B and two C scales. The first B scale runs from 100 to 112; the fortieth runs from 946 to 100 to 105. The first C scale runs from 100 to 334; the fortieth runs from 308 to 325. The frame is attached to a mahogany base, and the object is housed in a mahogany case. A paper label appears to have been removed from the top of the case.
A paper of directions and rules for operating THACHER'S CALCULATING INSTRUMENT is glued to the top front of the base. A metal tag attached to the top back of the base is engraved: Keuffel & Esser (/) New York. The front right corner of the frame is stamped with numbers: 57 and 35. Presumably one of these is the serial number, but which one is not clear. In either case, the low number and the shape of the frame suggest that this example is the earliest Thacher cylindrical slide rule in the collections. Model 1740 sold for $30.00 in 1887.
Robert B. Steffes of the U.S. Bureau of Labor Statistics donated this instrument to the Smithsonian in 1970.
See also MA.312866 and 1987.0107.08.
References: Wayne E. Feely, "Thacher Cylindrical Slide Rules," The Chronicle of the Early American Industries Association 50 (1997): 125–127; Catalogue of Keuffel & Esser (New York, 1887), 128. This was the first K&E catalog to list the model 1740.
Location
Currently not on view
date made
1882-1887
maker
Keuffel & Esser Co.
Stanley, William Ford
ID Number
1987.0808.01
catalog number
1987.0808.01
accession number
1987.0808

Stanley Slide Rule Invented by James Hogg

By the late 19th century, several American inventors proposed special-purpose slide rules. One of them was James Hogg (1851–1930), an English mechanical engineer who came to the United States in 1880 and soon was overseer at the Globe Worsted Mill in Lawrence, Mass.
Description
By the late 19th century, several American inventors proposed special-purpose slide rules. One of them was James Hogg (1851–1930), an English mechanical engineer who came to the United States in 1880 and soon was overseer at the Globe Worsted Mill in Lawrence, Mass. During his time in Lawrence, Hogg devised this slide rule and arranged to have it manufactured by the Stanley Rule & Level Company of New Britain, Conn. He went on to patent a spindle for spinning machies (U.S. Patent 401,703) and feeding mechanisms for carding machines (U.S. Patents 562,610; 686,071; and 686,072).
This instrument is a wooden linear slide rule with a metal slide and metal edges on all four sides. The scales on the top of the base are lettered A, B, and C; the scales on the slide are lettered D and E; and the scales on the bottom of the base are lettered F, NUM, and LOG. The A and NUM scales range from 1 to 10, divided logarithmically. The B, C, D, and E scales range from 1 to 10 and then from 1 to 10 again, divided logarithmically. The F scale is divided like the B, C, D, and E scales, but runs in the opposite direction. The LOG scale is a scale of equal parts, ranging from 1 to 100 and divided in increments of one-half. The back of the slide is a twelve-inch scale divided to tenths of an inch and to eighths of an inch.
The back of the rule also has a twelve-inch scale divided to tenths of an inch on one edge and a twelve-inch scale divided to eighths of an inch on the other edge. In between are tables providing conversion factors from the volumes of geometric solids to cubic inches and feet; 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. Compare to 1981.0934.01.
The back is marked: PAT. APPLIED FOR IMPROVED SLIDE RULE (/) ARRANGED & CONSTRUCTED BY (/) JAS. HOGG LAWRENCES MASS. U.S.A. (/) MANUFACTURED BY (/) STANLEY RULE & LEVEL CO. NEW BRITAIN, CONN. No patent has been found for the instrument.
Hogg moved from Lawrence in 1888 and subsequently worked for Stephen Sanford & Sons, Inc., in Amsterdam, N.Y., and the Bigelow Carpet Company in Lowell, Mass. An 1888 advertisement reported that the rule and instruction book sold together for $4.00. The instrument was still on sale in 1908, with instruction book, for a price of $3.50.
References: James Hogg, A Practical Course in Instruction with Hogg's Improved Slide-Rule in Arithmetic and Mensuration (Boston: Rand, Avery Co., 1887); "James Hogg," Transactions of the American Society of Mechanical Engineers 52 (1930): 77; "Hogg's Improved Slide Rule," Wade's Fibre & Fabric 7, no. 182 (August 25, 1888): 203, 209; "New Publications," Textile World Record 36 (1908): 631; Thomas Wyman, "Slide Rules of the Stanley Rule & Level Company and other American Makers," The Chronicle of the Early American Industries Association 54, no. 3 (2001): 114–117.
Location
Currently not on view
date made
1880-1888
maker
Stanley Rule and Level Company
ID Number
1991.0556.01
catalog number
1991.0556.01
accession number
1991.0556

Patent Model for Simplex Slide Rule Clasp Invented by Rudolph C. Smith

This ten-inch, linear one-sided slide rule has scales on the base labeled 3 and 2. On one side of the slide, scales are labeled 4 and 1. On the other side are scales labeled S and T and a scale of equal parts, which divides each inch into 50 increments.
Description
This ten-inch, linear one-sided slide rule has scales on the base labeled 3 and 2. On one side of the slide, scales are labeled 4 and 1. On the other side are scales labeled S and T and a scale of equal parts, which divides each inch into 50 increments. The 4, 1, and 2 scales are identical, divided logarithmically from 1 to 10 twice (like the A and B scales on a Mannheim slide rule). The 3 scale is graduated logarithmically once from 1 to 10 (like the C and D scales on a Mannheim rule, although the numbers on this scale are marked with superscript 2s; i.e. 22).
Under the slide is a scale of centimeters numbered from 27 to 51 and divided to millimeters. The upper edge of the instrument is beveled and has a scale of inches divided to 32nds of an inch. The front edge has a scale of centimeters numbered from 1 to 25 and divided to millimeters.
There is also a brass clasp (detached at present) that holds three paper strips underneath the instrument, so that they may be pulled or fanned out for reference. Smith submitted this model when he patented this clasp in 1887. The strips contain 39 sets of formulas and conversion factors useful to civil engineers, including the weight and strength of materials and the power of engines and pumps. Smith copyrighted these strips in 1884 and 1886. See also his pamphlet, Smith's Slide Rule Formulæ ([New York, 1884]).
Rudolph Charles Smith of Yonkers, N.Y., received more than twenty patents for elevator components and slide rules from the 1880s to 1912. He apparently worked for Otis Brothers & Co., since many of the patents were assigned to that firm or to National Company of Illinois, which merged with Otis Brothers and other firms in 1898 to form the Otis Elevator Company. Elisha Otis started the company in 1853 as Union Elevator Works to sell his safety elevator. His sons, Norton and Charles, adopted the Otis Brothers name in 1864.
According to an order form dated January 1889 held by the Smithsonian Institution Libraries, Smith's Patent Calculator sold in four forms. One had attached slips with formulae of interest to civil engineers, a second had formulae for marine engineers, a third had formulae for mechanical engineers, and a fourth was intended for "assayers, chemists, scientists, students." The instrument cost 50 cents with one set of attachments or 75 cents with all four sets. This example appears to be the instrument for civil engineers. An unsigned review of Florian Cajori's 1909 history of the slide rule criticized Cajori for ignoring Smith's contributions to popularizing the slide rule and educating Americans in its use.
References: Rudolph C. Smith, "Attachment for Calculating Scales" (U.S. Patent 357,346 issued February 8, 1887), "Slide-Rule for Logarithmic Calcuations" (U.S. Patent 450,640 issued April 21, 1891), "Calculating-Scale" (U.S. Patent 592,067 issued October 19, 1897), "Calculating-Scale" (U.S. Patent 746,888 issued December 15, 1903), "Calculating-Scale" (U.S. Patent 1,014,344 issued January 9, 1912); Annual Report of the Commissioner of Patents for the Year 1891 (Washington, D.C.: Government Printing Office, 1892), 339; Practical Applications of Smith's Electro-Calculator (New York, 1894); R. C. Smith, The International Book of Shorthand Computation ([New York, 1900]); "Elevator Trust Sued," New York Times, March 8, 1906; review of A History of the Logarithmic Slide Rule and Allied Instruments by Florian Cajori, Mines and Minerals 30, no. 12 (July 1910): 740.
Location
Currently not on view
date made
1887
maker
Smith, Rudolph C.
ID Number
MA.308973
catalog number
308973
accession number
89797

Keuffel & Esser 1740 Thacher Cylindrical Slide Rule

In 1881, Edwin Thacher, a "computing engineer" for the Keystone Bridge Company in Pittsburgh, Pennsylvania, received a patent for an improvement in slide rules. Thacher was a graduate of Rennselaer Polytechnic Institute who spent much of his career designing railway bridges.
Description
In 1881, Edwin Thacher, a "computing engineer" for the Keystone Bridge Company in Pittsburgh, Pennsylvania, received a patent for an improvement in slide rules. Thacher was a graduate of Rennselaer Polytechnic Institute who spent much of his career designing railway bridges. To assist in his calculations, he designed a cylindrical slide rule. Thacher's rule, though it fit on a desk, was equivalent to a conventional slide rule over 59 feet long. It had scales for multiplication and division and another scale, with divisions twice as large, for use in finding squares and square roots. But it had no trigonometric scales.
To produce his "calculating instrument," Thacher turned to the London firm of W. F. Stanley. The company even designed a special dividing engine for preparing the scales for the instrument. These were printed on paper sheets, which were pasted to the drum and the slats. In this example, the paper is also printed in italics on the right side: Patented by Edwin Thatcher [sic], C.E. Nov. 1st 1881. Divided by W. F. Stanley, London, 1882.
The drum is rotated with wooden handles. The cylinder of slats is held in place with a brass frame, which is affixed to a wooden base. A paper of DIRECTIONS AND RULES FOR OPERATING is lacquered to the front of the base. The rear of the base bears a small silver metal label engraved: Keuffel & Esser (/) New York. F. F. NICKEL is painted underneath the base.
Keuffel & Esser Company of New York sold versions of the Thacher cylindrical slide rule from at least 1883 until about 1950. There were two models, one with a magnifying glass (K&E model 1741, later K&E model 4013), and one without (K&E model 1740, later K&E 4012). This is a model 1740. The front right corner of the instrument's metal frame is engraved with the number 107. A paper K&E label on the inside lid of the instrument's mahogany case is marked in ink: 1740/661 (/) Thachers (/) Calculating (/)Instr. The top front of the bottom of the case is also carved with 661. In 1887, the model 1740 sold for $30.00.
Frank Ferdinand Nickel purchased this example around 1883 and donated it to the Smithsonian in 1945, through his son, Henry W. Nickel. The elder Nickel was born in Hanau, Germany, in 1857. He came to the United States around 1883 and worked as a mechanical engineer in New York, Ohio, Pennsylvania, and New Jersey. He also taught at Columbia University in the 1910s. He wrote Direct-Acting Steam Pumps (New York: McGraw-Hill, 1915).
See also 1987.0107.08 and 1987.0808.01.
References: Edwin Thacher, "Slide-Rule" (U.S. Patent 249,117 issued November 1, 1881); "Thacher's Calculating Instrument or Cylindrical Slide Rule," Engineering News 16 (18 December 1886): 410; Wayne E. Feely, "Thacher Cylindrical Slide Rules," The Chronicle of the Early American Industries Association 50 (1997): 125–127; Wilfred Scott Downs, ed., "Nickel, Frank F.," Who's Who in Engineering, vol. 3 (New York, 1931), 957; Catalogue of Keuffel & Esser (New York, 1887), 128. This was the first K&E catalog to list the model 1740.
Location
Currently not on view
date made
ca 1883
maker
Stanley, William Ford
Keuffel & Esser Co.
ID Number
MA.312866
accession number
169701
catalog number
312866

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