A variety of rulers

A 2 meter carpenter's rule

Retractable flexible rule or tape measure

A closeup of a steel rule

A ruler, sometimes called a rule or line gauge, is an instrument used in geometry, technical drawing, printing and engineering/building to measure distances and/or to rule straight lines. Strictly speaking, the ruler is essentially a straightedge used to rule lines^{[citation needed]}, but typically the ruler also contains calibrated lines to measure distances.^[1]

Types[link]

Rulers have long been made of wood in a wide range of sizes. However, they are not all wooden. Plastics have been used since they were invented; they can be molded with length markings instead of being scribed. Metal is 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 inches or 30 cm in length is useful for a ruler to be kept on a desk to help in drawing. Shorter rulers are convenient for keeping in a pocket.^[2] Longer rulers, e.g., 18 inches (45 cm) 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 Classically, long measuring rods were used for larger projects, now superseded by tape measure or laser rangefinders.

Desk rulers are used for three main purposes: to measure, to aid in drawing straight lines and as a straight guide for cutting and scoring with a blade. Practical rulers have distance markings along their edges.

A type of ruler used in the printing industry is called a line gauge. These may be made from a variety of materials, typically metal or clear plastic. Units of measurement on a basic line gauge usually include inches, agate, picas, and points. More detailed line gauges may contain sample widths of lines, samples of common type in several point sizes, etc.

Measuring instruments similar in function to rulers are made portable by folding (carpenter's folding rule) or retracting into a coil (metal tape measure) when not in use. When extended for use they are straight, like a ruler. The illustrations on this page show a 2-meter carpenter's rule which folds down to a length of 24 cm to easily fit in a pocket, and a 5-meter-long tape which retracts into a small housing.

A flexible length measuring instrument which is not necessarily straight in use is the tailor's fabric tape measure, a length of tape calibrated in inches and centimeters. It is used to measure around a solid body, e.g., a person's waist measurement, as well as linear measurement, e.g., inside leg. It is rolled up when not in use, taking up little space.

A contraction rule is made having larger divisions than standard measures to allow for shrinkage of a metal casting. They may also be known as a 'shrinkage or shrink rule.^[3]

A ruler software program can be used to measure pixels on a computer screen.

Ruler applications in geometry[link]

In geometry, a ruler without any marks on it (a straightedge) may be used only for drawing straight lines between points, not measuring. A straightedge is also used to help draw accurate graphs in algebra and other math subjects.

A ruler and compass construction refers to constructions using an unmarked ruler and a compass. It is possible to bisect an angle into two equal parts with ruler and compass. It can be proved, 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, should two marks be allowed on the ruler, the problem becomes solvable.

History[link]

A wooden carpenter's rule and other tools found on board the 16th century carrack Mary Rose.

Rulers made of Ivory were in use by the Indus Valley Civilization period prior to 1500 BC.^[4] Excavations at Lothal (2400 BC) have yielded one such ruler calibrated to about ¹⁄₁₆ in (1.6 mm).^[4] Ian Whitelaw holds that the Mohenjo-Daro ruler is divided into units corresponding to 1.32 in (33.5 mm) and these are marked out in decimal subdivisions with amazing accuracy, to within 0.005 in (0.13 mm). Ancient bricks found throughout the region have dimensions that correspond to these units.^[5]

Anton Ullrich invented the folding ruler in 1851.

Philosophy[link]

Ludwig Wittgenstein famously used rulers as an example in his discussion of language games in the Philosophical Investigations. 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, but that 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[link]

• Dividing engine
• Geometry template
• Golomb ruler
• Measuring rod
• Rolling ruler
• Scale rulers: architect's scale and engineer's scale

References[link]

Notes[link]

Bibliography[link]

• Whitelaw, Ian (2007). A Measure of All Things: The Story of Man and Measurement. Macmillan. ISBN 0-312-37026-1.

External links[link]

Look up ruler in Wiktionary, the free dictionary.

Wikimedia Commons has media related to: Length measuring devices

Brandon Boyd
Background information
Birth name	Brandon Charles Boyd
Also known as	The Invisible Floating Torso Man (Make Yourself) Happy Knappy (Fungus Amongus) Brandon of the Jungle (Enjoy Incubus) Cornelius (S.C.I.E.N.C.E.)
Born	(1976-02-15) February 15, 1976 (age 36) Van Nuys, California, U.S.
Genres	Alternative rock
Occupations	Service Advisor
Instruments	Vocals, guitar, percussion, didjeridoo, djembe
Years active	1991–present
Labels	Epic Records Immortal Records Sony Records
Associated acts	Incubus

Brandon Charles Boyd (born February 15, 1976, in Van Nuys, California) is an American musician, author, and visual artist. He is best known as the lead vocalist of the American rock band Incubus.

Early life and Incubus[link]

Boyd graduated from Calabasas High School with Michael Einziger and José Pasillas in 1994 and attended Moorpark College for two years before committing to Incubus. Brandon grew up in Calabasas, CA with Ricky Taylor who inspired him to write music. His parents, Priscilla "Dolly" Wiseman and Charles Boyd, both of whom had experience in entertainment, had nurtured his artistic side since he was a child.^[1] Other musical family members include his younger brother, Jason Boyd, the former lead singer of the band Audiovent, cousin Sam Boyd, a songwriter and touring musician, as well as cousin Robert "Berto Chico" Boyd, an accomplished Flamenco guitarist. In an interview, Boyd explained that he had "yet to stumble across his best work" because he lacked the ability to read music.^[2]

Boyd designed concert fliers advertising their early performances. At first, Boyd had copied several drawings from a sex education book that Einziger's mother had given them, but he decided to stop using it after several prospective fans had been confused by their fliers ("What kind of band is this?").^[3] Boyd is also known for playing several instruments such as the didgeridoo and djembe. He also has some guitar parts during live performances.

His voice was part of what enticed Sony's Epic/Immortal Records, and the band was signed in 1996. The band's first two releases on the label, Enjoy Incubus and S.C.I.E.N.C.E. went largely unnoticed, but subsequent releases Make Yourself and Morning View were commercial successes. The band's 2004 release A Crow Left of the Murder... has continued their success, nominating the band for Best Hard Rock Performance in the 2005 Grammy Awards. On November 28, 2006, the band released Light Grenades. On June 16, 2009, Incubus released a greatest hits album titled Monuments and Melodies.

In 2011 Incubus finished their 7th studio album If Not Now, When?, which was released on July 12, 2011, followed then by a tour.

Literature and fine art[link]

Brandon Boyd has written two books. The first, written in 2003, was White Fluffy Clouds: Found Inspiration Moving Forward. It was published by Endophasia Publications and mainly consists of his artwork, photography, song lyrics from Incubus, and additional writings and thoughts. His more recent publication, From the Murks of the Sultry Abyss, was also published by Endophasia in 2007.

In recent years, Brandon Boyd has focused on making fine art, specifically painting, and on September 8, 2008 celebrated the opening of his first solo show,^[4] titled "Ectoplasm," at Mr. Musichead Gallery in Los Angeles, California.

Solo career[link]

On July 6, 2010, Boyd announced that his debut solo album, The Wild Trapeze was released.^[5] On June 21, 2010, a music video for Boyd's first single from The Wild Trapeze, entitled "Runaway Train," was released online. A second music video was released for the album, for the song "Last Night a Passenger" in October 2010.

Tattoos[link]

Boyd is known for his wide variety of tattoos. On his forearms he carries the widely known Buddhist mantra Om Mani Padme Hum, referring to the qualities of generosity, ethics, patience, diligence, renunciation and wisdom. Underneath that is a koi fish in red ink designed by friend and bandmate, José Pasillas. On the inside of his right arm he has several tattoos, one once again incorporating the Tibetan mantra and another designed after Sarah Kerrigan^{[citation needed]}. Following the release of their album "A Crow Left of the Murder," he got an elaborate back tattoo featuring the common image of the All Seeing-Eye embedded in a pyramid.^[6] He also has a tattoo of the Eye of Horus on his right ankle. Other tattoos include his parents' names (Priscilla and Charles) on his forearms, an owl on his back, one teardrop on his index finger on both hands, and a picture inspired by Aubrey Beardsley's famous art, "The Peacock Skirt", on his left arm.

Personal life[link]

Brandon Boyd has reportedly dated models and personalities such as Jessica Miller, Baelyn Neff, Vanessa Marra, Lisa Snowdon, Carolyn Murphy, and Jo Bourne-Taylor.^[7]

Discography[link]

With Incubus

• Fungus Amongus (1995)
• S.C.I.E.N.C.E. (1997)
• Make Yourself (1999)
• Morning View (2001)
• A Crow Left of the Murder... (2004)
• Light Grenades (2006)
• Monuments and Melodies (2009)
• If Not Now, When? (2011)

Solo

• The Wild Trapeze (2010)

References[link]

External links[link]