Howlett Protractor Signed by Elliott Bros.
date: label: date made
content: 1873-1916
name: label: maker
content: Elliott Bros.
notes: label: Description
content: In 1837, Samuel Burt Howlett (1794–1874), chief draftsman to the Board of Ordnance in Great Britain, described a semicircular protractor for use in plotting surveys. The instrument overcame perceived shortcomings with utilizing circular protractors or theodolites in rustic field conditions. He indicated his design had already been available for purchase for a few years. Indeed, by 1847, treatises and textbooks on surveying, military engineering, and mathematical instruments widely discussed the "Howlett Protractor."
label: Description
content: This example is in the standard semicircular form and is made of brass. The protractor measures 23 cm by 11 cm. It is graduated to half-degrees and marked by tens from 0° to 180° and from 180° to 360°, both in the clockwise direction. There are notches on the interior of the protractor at 0, 90, and 180 degrees. There is an arm fastened to the origin point. The arm bears a vernier scale marked by fives from 15 to 25, then from 5 to 15. There is a thumb-screw on the vernier; two more thumb-screws with pointer tips are on the base of the protractor and are for securing the protractor to a surveying or engineering drawing.
label: Description
content: The base of the protractor bears a maker's mark: Elliott Bros. (/) LONDON. Frederick and Charles Elliott gave this name to their firm in 1854, after four years of partnership with their father, the instrument maker William Elliott. However, they did not start using this form of signature on their products until 1873. This object thus dates between 1873 and 1916, when the firm changed its signature to "Elliott Bros (London) Ltd" and focused on electrical devices rather than drawing instruments. The protractor is stored in its original wooden case, which is lined with blue velvet. Two brass hooks secure the lid. "Not R. Blu" is written in blue pencil on the bottom of the case.
label: Description
content: References: Samuel B. Howlett, "A New Method of Plotting a Survey," <I>Papers on Subjects Connected with the Duties of the Corps of Royal Engineers</I> 1 (1837): 65–67; Howlett Papers, Additional Manuscripts 871–884, Durham University Library, Archives and Special Collections, Durham, England; Basil Jackson, <I>A Treatise on Military Surveying</I>, 3rd ed. (London, 1847), 55–61; Gloria Clifton, “An Introduction to the History of Elliott Brothers up to 1900,” <I>Bulletin of the Scientific Instrument Society</I> 36 (1993): 2–7; H. R. Bristow, “Elliott, Instrument Makers of London. Products, Customers and Development in the 19th Century,” <I>Bulletin of the Scientific Instrument Society</I> 36 (1993): 8–11; H. R. Bristow, "Lewisham to Oxford: The Elliott Archive and Instrument Collection," <I>Bulletin of the Scientific Instrument Society</I> 109 (2011): 14–15; James Stewart, "On the Use of the Semicircular Protractor, with a Description of an Improved Form of that Instrument," <I>Transactions and Proceedings of the New Zealand Institute</I> 3 (1870): 316–318.
label: Location
content: Currently not on view
place: label: place made
content: United Kingdom: England, London
topic: label: Subject
content: Mathematics
label: Subject
content: Protractor
label: Subject
content: Surveying
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Protractors
creditLine: label: Credit Line
content: Gift of Mrs. Russell Monroe
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MA.314902
label: accession number
content: 212171
label: catalog number
content: 314902
objectType: label: Object Name
content: protractor
physicalDescription: label: Physical Description
content: velvet (overall material)
label: Physical Description
content: hardwood (overall material)
label: Physical Description
content: brass (overall material)
label: Measurements
content: overall: 4 cm x 27 cm x 13 cm; 1 9/16 in x 10 5/8 in x 5 1/8 in