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A ruler, sometimes called a rule, scale or a line gauge or metre/meter stick, is an instrument used to make length measurements, whereby a length is read from a series of markings called "rules" along an edge of the device. Usually, the instrument is rigid and the edge itself is a straightedge ("ruled straightedge"), which additionally allows one to draw straighter lines.
Variants
Rulers have long been made from different materials and in multiple sizes. Historically, they were mainly wooden but plastics have also been used. They can be created with length markings instead of being scribed. Metal is also used for more durable rulers for use in the workshop; sometimes a metal edge is embedded into a wooden desk ruler to preserve the edge when used for straight-line cutting. 12 in or 30 cm in length, although some can go up to 100cm, it is useful for a ruler to be kept on a desk to help in drawing. Shorter rulers are convenient for keeping in a pocket. Longer rulers, e.g., 46 cm (18 in), are necessary in some cases. Rigid wooden or plastic yardsticks, 1 yard long, and meter sticks, 1 meter long, are also used. Classically, long measuring rods were used for larger projects, now superseded by the tape measure, the surveyor's wheel or laser rangefinders.
Use in geometry
In geometry, straight lines between points may be drawn using a straightedge (ruler without any markings on it). Furthermore, it is also used to draw accurate graphs and tables.
A ruler and compass construction is a construction that uses a ruler and a compass. It is possible to bisect an angle into two equal parts with a ruler and compass. It can be proven, though, that it is impossible to divide an angle into three equal parts using only a compass and straightedge — the problem of angle trisection. However, if two marks be allowed on the ruler, the problem becomes solvable.
History
In the history of measurement many distance units have been used which were based on human body parts such as the cubit, hand and foot and these units varied in length by era and location. In the late 18th century the metric system came into use and has been adopted to varying degrees in almost all countries in the world.
The oldest preserved measuring rod is a copper-alloy bar that dates from c. 2650 BC and was found by the German Assyriologist Eckhard Unger while excavating at the Sumerian city of Nippur (present-day Iraq).
Rulers made of ivory were in use by the Indus Valley civilization period prior to 1500 BC. Excavations at Lothal (2400 BC) have yielded one such ruler calibrated to about 1.6 millimetres (1⁄16 in). Ian Whitelaw holds that the Mohenjo-Daro ruler is divided into units corresponding to 33.5 millimetres (1.32 in) and these are marked out in decimal subdivisions with amazing accuracy, to within 0.13 millimetres (0.005 in). Ancient bricks found throughout the region have dimensions that correspond to these units.
Anton Ullrich invented the folding ruler in 1851. Frank Hunt later made the flexible ruler in 1902.
Curved and flexible rulers
The equivalent of a ruler for drawing or reproducing a smooth curve, where it takes the form of a rigid template, is known as a French curve. A flexible device that can be bent to the desired shape is known as a flat spline, or (in its more modern incarnation) a flexible curve. Historically, a flexible lead rule used by masons that could be bent to the curves of a molding was known as a lesbian rule.
Philosophy
Ludwig Wittgenstein famously used rulers as an example in his discussion of language games in the Philosophical Investigations (1953). He pointed out that the standard meter bar in Paris was the criterion against which all other rulers were determined to be one meter long. However, there was no analytical way to demonstrate that the standard meter bar itself was one meter long. It could only be asserted as one meter as part of a language game.
See also
- Accuracy and precision – Characterization of measurement error
- Dividing engine – Device for marking graduations on measuring instruments
- Golomb ruler – Set of marks along a ruler such that no two pairs of marks are the same distance apart
- Measuring instrument – Measuring instruments which monitor and control a process
- Measuring rod – Tool used to physically measure lengths
- Rolling ruler
- Scales:
- Architect's scale – Tool used for measuring at a fixed ratio
- Metric scale – Tool used for measuring at a fixed ratio and
- Engineer's scale – Tool used for measuring at a fixed ratio
- Significant figures – Any digit of a number within its measurement resolution, as opposed to spurious digits
- Technical drawing tool – Tools and instruments used for accurate and precise manual drafting
References
- "ruler noun - Definition, pictures, pronunciation and usage notes - Oxford Advanced Learner's Dictionary at OxfordLearnersDictionaries.com". www.oxfordlearnersdictionaries.com. Archived from the original on 25 October 2017. Retrieved 25 April 2018.
- "Steel Rule Has Pocket Clip For Use As A Depth Gauge", Popular Science, December 1935, p. 887 bottom right.
- Klein, Herbert A. The science of measurement: a historical survey. Reprint, unabridged, corr. republ. der Ausg. New York, Simon & Schuster, 1974. ed. New York, NY: Dover, 1988. Print.
- Whitelaw, p. 14.
- Whitelaw, p. 15.
- "Flexible Ruler Invented by Frank G. Hunt". National Museum of National History. Archived from the original on 30 June 2016. Retrieved 7 June 2016.
- "lesbian rule". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.) (subscription required)
Bibliography
- Cherry, Dan. "Collector's guide to rules", Furniture & Cabinetmaking, no. 259, July 2017, ISSN 1365-4292, pp. 52–6
- Rees, Jane and Mark (2010). The Rule Book: Measuring for the Trades. Lakeville, MN: Astragal Press ISBN 978-1-931626-26-2 OCLC 907853704
- Russell, David R.; with photography by James Austin and foreword by David Linley (2010). Antique Woodworking Tools: Their Craftsmanship from the Earliest Times to the Twentieth Century, Cambridge: John Adamson ISBN 978-1-898565-05-5 OCLC 727125586, pp. 64–74
- Whitelaw, Ian (2007). A Measure of All Things: The Story of Man and Measurement. Macmillan ISBN 0-312-37026-1 OCLC 938084552
This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Ruler news newspapers books scholar JSTOR November 2023 Learn how and when to remove this message A ruler sometimes called a rule scale or a line gauge or metre meter stick is an instrument used to make length measurements whereby a length is read from a series of markings called rules along an edge of the device Usually the instrument is rigid and the edge itself is a straightedge ruled straightedge which additionally allows one to draw straighter lines A variety of rulersA carpenter s ruleRetractable flexible rule or tape measureA closeup of a steel rulerA ruler in combination with a letter scaleVariantsRulers have long been made from different materials and in multiple sizes Historically they were mainly wooden but plastics have also been used They can be created with length markings instead of being scribed Metal is also used for more durable rulers for use in the workshop sometimes a metal edge is embedded into a wooden desk ruler to preserve the edge when used for straight line cutting 12 in or 30 cm in length although some can go up to 100cm it is useful for a ruler to be kept on a desk to help in drawing Shorter rulers are convenient for keeping in a pocket Longer rulers e g 46 cm 18 in are necessary in some cases Rigid wooden or plastic yardsticks 1 yard long and meter sticks 1 meter long are also used Classically long measuring rods were used for larger projects now superseded by the tape measure the surveyor s wheel or laser rangefinders Use in geometryIn geometry straight lines between points may be drawn using a straightedge ruler without any markings on it Furthermore it is also used to draw accurate graphs and tables A ruler and compass construction is a construction that uses a ruler and a compass It is possible to bisect an angle into two equal parts with a ruler and compass It can be proven though that it is impossible to divide an angle into three equal parts using only a compass and straightedge the problem of angle trisection However if two marks be allowed on the ruler the problem becomes solvable HistoryThe Nippur cubit rod c 2650 BC in the Archeological Museum of Istanbul TurkeyA wooden carpenter s rule and other tools found on board the 16th century carrack Mary Rose In the history of measurement many distance units have been used which were based on human body parts such as the cubit hand and foot and these units varied in length by era and location In the late 18th century the metric system came into use and has been adopted to varying degrees in almost all countries in the world The oldest preserved measuring rod is a copper alloy bar that dates from c 2650 BC and was found by the German Assyriologist Eckhard Unger while excavating at the Sumerian city of Nippur present day Iraq Rulers made of ivory were in use by the Indus Valley civilization period prior to 1500 BC Excavations at Lothal 2400 BC have yielded one such ruler calibrated to about 1 6 millimetres 1 16 in Ian Whitelaw holds that the Mohenjo Daro ruler is divided into units corresponding to 33 5 millimetres 1 32 in and these are marked out in decimal subdivisions with amazing accuracy to within 0 13 millimetres 0 005 in Ancient bricks found throughout the region have dimensions that correspond to these units Anton Ullrich invented the folding ruler in 1851 Frank Hunt later made the flexible ruler in 1902 Curved and flexible rulersThe equivalent of a ruler for drawing or reproducing a smooth curve where it takes the form of a rigid template is known as a French curve A flexible device that can be bent to the desired shape is known as a flat spline or in its more modern incarnation a flexible curve Historically a flexible lead rule used by masons that could be bent to the curves of a molding was known as a lesbian rule PhilosophyLudwig Wittgenstein famously used rulers as an example in his discussion of language games in the Philosophical Investigations 1953 He pointed out that the standard meter bar in Paris was the criterion against which all other rulers were determined to be one meter long However there was no analytical way to demonstrate that the standard meter bar itself was one meter long It could only be asserted as one meter as part of a language game See alsoscience portalAccuracy and precision Characterization of measurement error Dividing engine Device for marking graduations on measuring instruments Golomb ruler Set of marks along a ruler such that no two pairs of marks are the same distance apart Measuring instrument Measuring instruments which monitor and control a processPages displaying short descriptions of redirect targets Measuring rod Tool used to physically measure lengths Rolling ruler Scales Architect s scale Tool used for measuring at a fixed ratioPages displaying short descriptions of redirect targets Metric scale Tool used for measuring at a fixed ratioPages displaying short descriptions of redirect targets and Engineer s scale Tool used for measuring at a fixed ratioPages displaying short descriptions of redirect targets Significant figures Any digit of a number within its measurement resolution as opposed to spurious digits Technical drawing tool Tools and instruments used for accurate and precise manual draftingReferences ruler noun Definition pictures pronunciation and usage notes Oxford Advanced Learner s Dictionary at OxfordLearnersDictionaries com www oxfordlearnersdictionaries com Archived from the original on 25 October 2017 Retrieved 25 April 2018 Steel Rule Has Pocket Clip For Use As A Depth Gauge Popular Science December 1935 p 887 bottom right Klein Herbert A The science of measurement a historical survey Reprint unabridged corr republ der Ausg New York Simon amp Schuster 1974 ed New York NY Dover 1988 Print Whitelaw p 14 Whitelaw p 15 Flexible Ruler Invented by Frank G Hunt National Museum of National History Archived from the original on 30 June 2016 Retrieved 7 June 2016 lesbian rule Oxford English Dictionary Online ed Oxford University Press Subscription or participating institution membership required subscription required BibliographyCherry Dan Collector s guide to rules Furniture amp Cabinetmaking no 259 July 2017 ISSN 1365 4292 pp 52 6 Rees Jane and Mark 2010 The Rule Book Measuring for the Trades Lakeville MN Astragal Press ISBN 978 1 931626 26 2 OCLC 907853704 Russell David R with photography by James Austin and foreword by David Linley 2010 Antique Woodworking Tools Their Craftsmanship from the Earliest Times to the Twentieth Century Cambridge John Adamson ISBN 978 1 898565 05 5 OCLC 727125586 pp 64 74 Whitelaw Ian 2007 A Measure of All Things The Story of Man and Measurement Macmillan ISBN 0 312 37026 1 OCLC 938084552Look up ruler in Wiktionary the free dictionary Wikimedia Commons has media related to Length measuring 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