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Compass (drawing Tool)
A compass, more accurately known as a pair of compasses, is a technical drawing instrument that can be used for inscribing circles or arcs. As dividers, it can also be used as a tool to mark out distances, in particular, on maps. Compasses can be used for mathematics, drafting, navigation and other purposes. Prior to computerization, compasses and other tools for manual drafting were often packaged as a set with interchangeable parts. By the mid-twentieth century, circle templates supplemented the use of compasses. Today those facilities are more often provided by computer-aided design programs, so the physical tools serve mainly a didactic purpose in teaching geometry, technical drawing, etc. Construction and parts Compasses are usually made of metal or plastic, and consist of two "legs" connected by a hinge which can be adjusted to allow changing of the radius of the circle drawn. Typically one leg has a spike at its end for anchoring, and the other leg holds a drawing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zirkel
Zirkel may refer to: * Zirkel (Studentenverbindung), a symbol used in European student societies * Dorsum Zirkel, a wrinkle ridge in Mare Imbrium on the Moon * Mount Zirkel, in the Rocky Mountains of Colorado * USS ''Zirkel'' (ID-3407), a cargo ship that served in the United States Navy from 1918 to 1919 * Albert Zirkel (1885–?), American wrestler who competed in the 1904 Summer Olympics * Ferdinand Zirkel (1838–1912), German geologist and petrographer {{disambiguation, surname German-language surnames Occupational surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nib (pen)
A nib is the part of a quill, dip pen, fountain pen, ball point or stylus which comes into contact with the writing surface in order to deposit ink. Different types of nibs vary in their purpose, shape and size, as well as the material from which they are made. History Quill The quill replaced the reed pen across Europe by the Early Middle Ages and remained the main writing tool of the West for nearly a thousand years until the 17th century. Quills are fashioned by cutting a nib into the end of a feather obtained from a fairly large bird, such as a goose, traditionally from its left wing. A quill has the advantage of being more durable and more flexible than a reed pen, and it can also retain ink in the hollow shaft of the feather, known as the calamus, allowing more writing time between ink dippings. The quill was in common use until the early 19th century and the advent of the metal nib. For business purposes, the quill was fairly quickly overtaken; however, it remains popular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Musée D'histoire Des Sciences De La Ville De Genève
The ''Musée d'histoire des sciences de la Ville de Genève'' (Museum of the History of Science of the City of Geneva) is a small museum in Switzerland dedicated to the history of science. Location The museum is located in the ''Villa Bartholoni'', designed by Félix-Emmanuel Callet, built in 1830 as a summer residence for Parisian bankers, Constant and Jean-François Bartholoni and extensively restored between 1985 and 1992. It is situated in the park ''La Perle du Lac'', overlooking Lake Geneva, adjacent to the Conservatory and Botanical Garden of the City of Geneva. Both the Villa and the museum itself are listed in the Swiss Inventory of Cultural Property of National and Regional Significance. Access The Museum is open daily from 10am to 5pm, except for 25 December and 1 January and admission is free. The museum receives over 250,000 visitors per year. History The museum was established in 1964 by the enthusiasm of ' (the Museum and review of the History of Science Asso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reduction Compass
The reduction compass or proportional dividers is a geometry tool with asymmetric-length branches to allow performing homothetic transformations, reproducing a pattern while enlarging or reducing its size and conserving angles. It was invented by Fabrizio Mordente before 1567. Use and principle The reduction compass is made of two branches, with two points each. Several types exist, including the following: * simple reduction compass: the pivot is fixed, and the enlargement factor is determined by the length difference between the small and long end of the branches; * mobile-headed reduction compass: the pivot is mounted on a slide, and its position determines the enlargement factor. File:Reduction compass-MHS 1880-IMG 3829-gradient.jpg, Simple reduction compass on display at the Musée d'Histoire des Sciences de la ville de Genève. File:Reduction compass-MHS 1914-IMG 3834-gradient.jpg, Sliding-pivot reduction compass by Nairne on London, 18th century. On display at the Musé ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sector (instrument)
The sector, also known as a proportional compass or military compass, was a major calculating instrument in use from the end of the sixteenth century until the nineteenth century. It is an instrument consisting of two rulers of equal length joined by a hinge. A number of scales are inscribed upon the instrument which facilitate various mathematical calculations. It was used for solving problems in proportion, multiplication and division, geometry, and trigonometry, and for computing various mathematical functions, such as square roots and cube roots. Its several scales permitted easy and direct solutions of problems in gunnery, surveying and navigation. The sector derives its name from the fourth proposition of the sixth book of Euclid, where it is demonstrated that similar triangles have their like sides proportional. Some sectors also incorporated a quadrant, and sometimes a clamp at the end of one leg which allowed the device to be used as a gunner's quadrant. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proportional Compass
The sector, also known as a proportional compass or military compass, was a major calculating instrument in use from the end of the sixteenth century until the nineteenth century. It is an instrument consisting of two rulers of equal length joined by a hinge. A number of scales are inscribed upon the instrument which facilitate various mathematical calculations. It was used for solving problems in proportion, multiplication and division, geometry, and trigonometry, and for computing various mathematical functions, such as square roots and cube roots. Its several scales permitted easy and direct solutions of problems in gunnery, surveying and navigation. The sector derives its name from the fourth proposition of the sixth book of Euclid, where it is demonstrated that similar triangles have their like sides proportional. Some sectors also incorporated a quadrant, and sometimes a clamp at the end of one leg which allowed the device to be used as a gunner's quadrant. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beam Compass
A beam compass is a compass with a beam and sliding sockets or cursors for drawing and dividing circles larger than those made by a regular pair of compasses. The instrument can be as a whole, or made on the spot with individual sockets (called trammel points) and any suitable beam. Draftsman's beam compass A draftsman's beam compass consists of a set of points and holders, mounted on a plated brass, aluminum, or German 'silver' rod. One end is generally locked down at the end of the rod, while the other has both rough and fine adjustments, though some are opposite in construction. The locked tip holder consists of a needle, for the centre of the radius, and the other holds either a lead clutch, or an inking nib. There are older variants which use a wooden beam. Another similar type is a Machinist or Engineers beam compass, which uses scribing points only, similar to ones used by woodworkers, except that its fine adjustment is generally more refined. These beam compasses can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euclid's Elements
The ''Elements'' ( grc, Στοιχεῖα ''Stoikheîa'') is a mathematical treatise consisting of 13 books attributed to the ancient Greek mathematician Euclid in Alexandria, Ptolemaic Egypt 300 BC. It is a collection of definitions, postulates, propositions ( theorems and constructions), and mathematical proofs of the propositions. The books cover plane and solid Euclidean geometry, elementary number theory, and incommensurable lines. ''Elements'' is the oldest extant large-scale deductive treatment of mathematics. It has proven instrumental in the development of logic and modern science, and its logical rigor was not surpassed until the 19th century. Euclid's ''Elements'' has been referred to as the most successful and influential textbook ever written. It was one of the very earliest mathematical works to be printed after the invention of the printing press and has been estimated to be second only to the Bible in the number of editions published since the first print ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euclid
Euclid (; grc-gre, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the '' Elements'' treatise, which established the foundations of geometry that largely dominated the field until the early 19th century. His system, now referred to as Euclidean geometry, involved new innovations in combination with a synthesis of theories from earlier Greek mathematicians, including Eudoxus of Cnidus, Hippocrates of Chios, Thales and Theaetetus. With Archimedes and Apollonius of Perga, Euclid is generally considered among the greatest mathematicians of antiquity, and one of the most influential in the history of mathematics. Very little is known of Euclid's life, and most information comes from the philosophers Proclus and Pappus of Alexandria many centuries later. Until the early Renaissance he was often mistaken for the earlier philosopher Euclid of Megara, causing his biogr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plane Geometry
Euclidean geometry is a mathematical system attributed to ancient Greek mathematician Euclid, which he described in his textbook on geometry: the '' Elements''. Euclid's approach consists in assuming a small set of intuitively appealing axioms (postulates) and deducing many other propositions (theorems) from these. Although many of Euclid's results had been stated earlier,. Euclid was the first to organize these propositions into a logical system in which each result is '' proved'' from axioms and previously proved theorems. The ''Elements'' begins with plane geometry, still taught in secondary school (high school) as the first axiomatic system and the first examples of mathematical proofs. It goes on to the solid geometry of three dimensions. Much of the ''Elements'' states results of what are now called algebra and number theory, explained in geometrical language. For more than two thousand years, the adjective "Euclidean" was unnecessary because no other sort of geometry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compass-and-straightedge Construction
In geometry, straightedge-and-compass construction – also known as ruler-and-compass construction, Euclidean construction, or classical construction – is the construction of lengths, angles, and other geometric figures using only an idealized ruler and a pair of compasses. The idealized ruler, known as a straightedge, is assumed to be infinite in length, have only one edge, and no markings on it. The compass is assumed to have no maximum or minimum radius, and is assumed to "collapse" when lifted from the page, so may not be directly used to transfer distances. (This is an unimportant restriction since, using a multi-step procedure, a distance can be transferred even with a collapsing compass; see compass equivalence theorem. Note however that whilst a non-collapsing compass held against a straightedge might seem to be equivalent to marking it, the neusis construction is still impermissible and this is what unmarked really means: see Markable rulers below.) More formall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dividers
A caliper ( British spelling also calliper, or in plurale tantum sense a pair of calipers) is a device used to measure the dimensions of an object. Many types of calipers permit reading out a measurement on a ruled scale, a dial, or a digital display. Some calipers can be as simple as a compass with inward or outward-facing points, but no scale. The tips of the caliper are adjusted to fit across the points to be measured and the dimension read by measuring between the tips with another measuring tool, such as a ruler. It is used in many fields such as mechanical engineering, metalworking, forestry, woodworking, science and medicine. Plural vs. singular A single tool might be referred to as a "caliper" or as "calipers", like a pair of scissors or glasses (a "plural only" or ''plurale tantum'' form). In colloquial usage, the phrase "pair of verniers" or just " vernier" might refer to a vernier caliper. Colloquially these phrases can also refer to dial calipers, although they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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