Thread: Level & Plumb
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Old 08-06-2014, 12:15 AM   #12
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The compass was invented in China, during the Han Dynasty between the 2nd century BC and 1st century AD.. The first compasses were made of lodestone, a naturally magnetized ore of iron.. Ancient Chinese people found that if a lodestone was suspended so it could turn freely, it would always point in the same direction, toward the magnetic poles. Early compasses were used for Geomancy "in the search for gems and the selection of sites for houses," but were later adapted for navigation during the Song Dynasty in the 11th century.. Later compasses were made of iron needles, magnetized by striking them with a lodestone..The dry compass was invented in medieval Europe around 1300..This was supplanted in the early 20th century by the liquid-filled magnetic compass..Xǔ Yǎhuì states.."No one can know how many oracle bones, prior to 1899, were ground up by traditional Chinese pharmacies and disappeared into peoples' stomachs"..Magnetism was originally used, not for navigation, but for geomancy and fortune-telling by the Chinese. The earliest Chinese magnetic compasses were probably not designed for navigation, but rather to order and harmonize their environments and buildings in accordance with the geomantic principles of feng shui..These early compasses were made with lodestone, a form of the mineral magnetite that is a naturally-occurring magnet and aligns itself with the Earth’s magnetic field..Cartilage oligomeric matrix protein is a protein that in humans is encoded by the COMP gene..St Vallier in Drôme, was the birthplace of one of France's most famous courtesans, the noble-born Diane de Poitiers (1499-1566), long-term mistress of King Henri II (1547-1559)..The Saoü Forest is known for its climbing paths..The oracle bones are mostly tortoise plastrons (ventral or belly shells, probably female) and ox scapulae (shoulder blades), although some are the carapace (dorsal or back shells) of tortoises, and a few are ox rib bones,scapulae of sheep, boars, horses and deer, and some other animal bones..The skulls of deer, oxen and humans have also been found with inscriptions on them, although these are very rare and appear to have been inscribed for record keeping or practice rather than for actual divination..Comp is a hamlet in the Se7enoaks District, in the English county of Kent...

The first recorded use of a 48 position mariner's compass on sea navigation was noted in The Customs of Cambodia by Yuan Dynasty diplomat Zhou Daguan, he described his 1296 voyage from Wenzhou to Angkor Thom in detail; when his ship set sail from Wenzhou, the mariner took a needle direction of “ding wei” position, which is equivalent to 22.5 degree SW. After they arrived at Baria, the mariner took "Kun Shen needle", or 52.5 degree SW.. Zheng He's Navigation Map, also known as "The Mao Kun Map", contains a large amount of detail "needle records" of Zheng He's expeditions..However, there are questions over diffusion, because of the apparent failure of the Arabs to function as possible intermediaries between East and West because of the earlier recorded appearance of the compass in Europe (1190) than in the Muslim world (1232, 1242, and 1282)..The earliest reference to an iron fish-like compass in the Islamic world occurs in a Persian talebook from 1232.. This fish shape was from a typical early Chinese design.. The earliest Arabic reference to a compass — in the form of magnetic needle in a bowl of water — comes from the Yemeni sultan and astronomer Al-Ashraf in 1282..He also appears to be the first to make use of the compass for astronomical purposes..A bearing compass is a magnetic compass mounted in such a way that it allows the taking of bearings of objects by aligning them with the lubber line of the bearing compass..The use of a compass as a direction finder underground was pioneered by the Tuscan mining town Massa where floating magnetic needles were employed for determining tunneling and defining the claims of the various mining companies as early as the 13th century..A thumb compass is a type of compass commonly used in orienteering, a sport in which map reading and terrain association are paramount..Small compasses found in clocks, mobile phones, and other electronic devices are solid-state compasses, usually built out of 2 or 3 magnetic field sensors that provide data for a microprocessor.. The correct heading relative to the compass is calculated using trigonometry(from Greek trigōnon, "triangle" + metron, "measure" is a branch of mathematics that studies relationships involving lengths and angles of triangles..The field emerged during the 3rd century BC from applications of geometry to astronomical Kerb studies..A Qibla compass or qiblah compass (sometimes also called qibla/qiblah indicator) is a modified compass used by Muslims to indicate the direction to face to perform ritual prayers..A compass is also subject to errors when the compass is accelerated or decelerated in an airplane or automobile. Depending on which of the Earth's hemispheres the compass is located and if the force is acceleration or deceleration the compass will increase or decrease the indicated heading. Compasses that include compensating magnets are especially prone to these errors, since accelerations tilt the needle, bringing it closer or further from the magnets.. Compasses used for wilderness land navigation should not be used in proximity to ferrous metal objects or electromagnetic fields (car electrical systems, automobile engines, steel pitons, etc.) as that can affect their accuracy..near the town of Se7enoaks, the villages of Borough Green (where the A-Z map company is based), St Mary's Platt (or just Platt), Wrotham Heath and the hamlet of Crouch..Thumb compasses are also often transparent so that an orienteer can hold a map in the hand with the compass and see the map through the compass... told you, it was sung by 2 women..Are you making a pass at me, Mrs. Bleylock..Not that I'm aware of, Sarah..She's that kind of a woman..When the hunger knows no reason! And then you'll need to feed.. She's..European..'Cause she's scared of getting old.. He held in his hand an antique silver lamp, in which the flame burned without a chimney or globe of any kind, throwing long quivering shadows as it flickered in the draught of the open door. The old man motioned me in with his right hand with a courtly gesture, saying in excellent English, but with a strange intonation.."Welcome to my house! Enter freely and of your own free will!"..
__________________ + Aga Khan IV receiving a gift of Trinitite - Get set for Ecky thump..I still shudder when I think about the warrior who came up behind me, and the thwacking he gave me with his pork sword...

Last edited by lightgiver; 08-06-2014 at 12:32 AM.
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