Darling, Brown and Sharpe Triangular Scale for Draughtsmen
date: label: date made
content: 1880–1892
name: label: maker
content: Darling, Brown & Sharpe
notes: label: Description
content: This nickel-plated steel instrument is crimped in the middle so that the scales along both edges are angled, giving the object the appearance of a triangle and bringing the scale closer to the draftsman's work. Both edges have scales dividing three inches into 96 parts and scales divided to 3" and numbered by ones from 0 to 3. One edge is marked: D.B.&S. PROV. R.I. Pt. Aug. 3. 80. The crimp is marked: No. 1.
label: Description
content: Draftsmen and architects could use this rule to make scale drawings in which 3" = 1'. Samuel Darling, a machinist who partnered between 1866 and 1892 with Joseph R. Brown and Lucian Sharpe of Providence, R.I., patented the general design in 1880. He desired a material that was not as susceptible to environmental changes as wood and a design that was not as heavy and expensive as the early forms of tubular triangular rules being manufactured by Darling, Brown & Sharpe and other firms.
label: Description
content: Darling, Brown & Sharpe sold the rule in graduations from 3" = 1' to 1/2" = 1' for $1.00. ID number 1977.0460.07 is the same rule with a 1" = 1' scale. For engineers, the rule was available divided from 20ths to 1,000ths of an inch. A "miscellaneous" version had different scales on each edge, graduated along the entire edge in increments from 1/16" to 1/100". In its advertisements, which used the English spelling for "draughtsmen," the company explained that putting only one scale on each instrument would help prevent draftsmen from becoming confused and making mistakes.
label: Description
content: The Brown & Sharpe Manufacturing Company continued to sell the rule after Darling's interest was bought out in 1892. The company then offered the scale in graduations down to 1/8" = 1' and increased the price to $1.25. By 1929, Brown & Sharpe offered only the miscellaneous version for $2.00. This example was owned by the renowned American designer of steam engines, Erasmus Darwin Leavitt Jr. (1836–1916), and donated by his granddaughter, Margaret van D. Rice.
label: Description
content: References: Samuel Darling, "Graduated Measuring Rule" (U.S. Patent 230,619 issued August 3, 1880); Kenneth L. Cope, intro., <i>A Brown & Sharpe Catalogue Collection, 1868 to 1899 </i> (Mendham, N.J.: The Astragal Press, 1997), 119, 160–161; Brown & Sharpe Mfg. Co., <i>Machinery and Tools</i>, no. 136 (Providence, R.I., 1916), 537–539; Brown & Sharpe Mfg. Co., <i>Small Tools Catalog No. 31</i> (Providence, R.I., 1929), 97; Henry Dexter Sharpe, <i>A Measure of Perfection: The History of Brown & Sharpe</i> (North Kingston, R.I.: Brown & Sharpe, 1949), http://www.roseantiquetools.com/id44.html.
label: Location
content: Currently not on view
place: label: place made
content: United States: Rhode Island, Providence
topic: label: Subject
content: Mathematics
label: Subject
content: Drafting, Engineering
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Scale Rules
creditLine: label: Credit Line
content: Gift of Margaret van D. Rice
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1977.0460.06
label: accession number
content: 1977.0460
label: catalog number
content: 336077
objectType: label: Object Name
content: rule, triangular
label: Object Name
content: scale rule
physicalDescription: label: Physical Description
content: steel (overall material)
label: Physical Description
content: nickel (overall material)
label: Measurements
content: overall: 1.3 cm x 31.2 cm x 2.4 cm; 1/2 in x 12 9/32 in x 15/16 in