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Calipers
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 in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caliper Detail View
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 in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pierre Vernier
Pierre Vernier (19 August 1580 at Ornans, Franche-Comté (at that time ruled by the Spanish Habsburgs, now part of France) – 14 September 1637, same location) was a French mathematician and instrument-inventor. He was the inventor and eponym of the vernier scale used in measuring devices. Life He was born in Ornans, France, in 1580. He was taught science by his father. He became captain and castellan of the castle at Ornans, for the King of Spain. He was also later councillor and director general of economy in the County of Burgundy. In Brussels, in the year 1631, Vernier published his treatise ''La construction, l'usage, et les propriétés du quadrant nouveau de mathématique'', and dedicated it to the Infanta. In it, he described the ingenious device which now bears his name, the vernier scale. To a quadrant with a primary scale in half degrees Vernier proposed to attach a movable sector, thirty-one half degrees in length but divided into thirty equal parts (each pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vernier Scale
A vernier scale, named after Pierre Vernier, is a visual aid to take an accurate measurement reading between two graduation markings on a linear scale by using mechanical interpolation, thereby increasing resolution and reducing measurement uncertainty by using vernier acuity to reduce human estimation error. It may be found on many types of instrument measuring linear or angular quantities, but in particular on a vernier caliper which measures internal or external diameter of hollow cylinders. The vernier is a subsidiary scale replacing a single measured-value pointer, and has for instance ten divisions equal in distance to nine divisions on the main scale. The interpolated reading is obtained by observing which of the vernier scale graduations is coincident with a graduation on the main scale, which is easier to perceive than visual estimation between two points. Such an arrangement can go to a higher resolution by using a higher scale ratio, known as the vernier constant. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometer (device)
A micrometer, sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw widely used for accurate measurement of components in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier, and digital calipers. Micrometers are usually, but not always, in the form of calipers (opposing ends joined by a frame). The spindle is a very accurately machined screw and the object to be measured is placed between the spindle and the anvil. The spindle is moved by turning the ratchet knob or thimble until the object to be measured is lightly touched by both the spindle and the anvil. Micrometers are also used in telescopes or microscopes to measure the apparent diameter of celestial bodies or microscopic objects. The micrometer used with a telescope was invented about 1638 by William Gascoigne, an English astronomer. History The word ''micrometer'' is a neoclassical coinage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Rome
In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 BC), Roman Republic (509–27 BC) and Roman Empire (27 BC–476 AD) until the fall of the western empire. Ancient Rome began as an Italic settlement, traditionally dated to 753 BC, beside the River Tiber in the Italian Peninsula. The settlement grew into the city and polity of Rome, and came to control its neighbours through a combination of treaties and military strength. It eventually dominated the Italian Peninsula, assimilated the Greek culture of southern Italy ( Magna Grecia) and the Etruscan culture and acquired an Empire that took in much of Europe and the lands and peoples surrounding the Mediterranean Sea. It was among the largest empires in the ancient world, with an estimated 50 to 90 million inhabitants, roughly 20% of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedro Nunes
Pedro Nunes (; Latin: ''Petrus Nonius''; 1502 – 11 August 1578) was a Portuguese mathematician, cosmographer, and professor, from a New Christian (of Jewish origin) family. Considered one of the greatest mathematicians of his time, Nunes is best known for his contributions to the nautical sciences (navigation and cartography), which he approached, for the first time, in a mathematical way. He was the first to propose the idea of a loxodrome, and was the inventor of several measuring devices, including the nonius (from which Vernier scale was derived), named after his Latin surname. Life Little is known about Nunes' early education, life or family background, only that he was born in Alcácer do Sal, his origins are Jewish and that his grandchildren spent a few years behind bars after they were accused by the Portuguese Inquisition of professing and secretly practicing Judaism. He studied at the University of Salamanca, maybe from 1521 until 1522, and at the University o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonius (device)
Nonius is a measuring tool used in navigation and astronomy named in honour of its inventor, Pedro Nunes (Latin: Petrus Nonius), a Portuguese author, mathematician and navigator. The nonius was created in 1542 as a system for taking finer measurements on circular instruments such as the astrolabe. The system was eventually adapted into the Vernier scale in 1631 by the French mathematician Pierre Vernier. Technical features The nonius was used to improve the astrolabe's accuracy. This consisted of a number of concentric circles traced on an instrument and dividing each successive one with one fewer divisions than the adjacent outer circle. On a standard scale of 90 degrees, there are an additional 44–45 concentric circles, with each divided into a specific unit size such that a scale unit on position n had an arc of 90/n degrees. Thus, the outermost quadrant would comprise 90° in 90 equal divisions, the next inner would have 89 divisions, the next 88 and so on. When an angle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
