Hinged Parallel Rule

Description:

This 6" ebony instrument has three blades, apparently cut from a single rectangle of wood, and is held together by intricate brass hinges. Surveyors, cartographers, navigators, and draftsmen began using parallel rules in the 18th century to easily draw parallel lines separated by various widths. These instruments were also used for reducing or enlarging scaled drawings.

According to the donor, the rule was brought to this continent by Alexander Matheson (1788–1866), an English officer who brought troops from the West Indies to fight against the Americans in the War of 1812. After the war, he helped build the Rideau Canal and settled near Perth, Ontario. His grandson, Alexander Matheson Richey (1826–1913), a lumberman who moved to Chicago, also used the instrument.

References: Maya Hambly, Drawing Instruments: 1580–1980 (London: Sotheby's Publications, 1988), 111; Ken W. Watson, "Smiths Falls Locks 28–31," Rideau Canal World Heritage Site, http://www.rideau-info.com/canal/history/locks/h28-31-smithsfalls.html; "The Town of Perth: The Settlement of Retired Military Heroes on 'the Scotch Line,'" Toronto Daily Mail (May 14, 1887), 6–7, 10; accession file.

Date Made: early 19th century

Location: Currently not on view

Place Made: United Kingdom: England

Subject: MathematicsDrafting, Engineering

Subject:

See more items in: Medicine and Science: Mathematics, Science & Mathematics, Parallel Rules, Measuring & Mapping

Exhibition:

Exhibition Location:

Credit Line: Gift of Ada B. Richey

Data Source: National Museum of American History

Id Number: MA.321753Catalog Number: 321753Accession Number: 243754

Object Name: parallel rule

Physical Description: brass (overall material)ebony (overall material)Measurements: overall: .2 cm x 15.2 cm x 3.6 cm; 3/32 in x 5 31/32 in x 1 13/32 in

Guid: http://n2t.net/ark:/65665/ng49ca746a5-0621-704b-e053-15f76fa0b4fa

Record Id: nmah_690219

Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.

If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.