FACTOID # 14: North Carolina has a larger Native American population than North Dakota, South Dakota and Montana combined.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Compass" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Compass

A compass (or mariner's compass) is a navigational instrument for finding directions on the Earth. It consists of a magnetized pointer free to align itself accurately with Earth's magnetic field, which is of great assistance in navigation. The face of the compass generally highlights the cardinal points of north, south, east and west. A compass can be used in conjunction with a marine chronometer to calculate longitude) and a sextant to calculate latitude, providing a very accurate navigation capability. This device greatly improved maritime trade by making travel safer and more efficient. An early form of the compass was invented in China in the 11th century. The familiar mariner's compass was invented in Europe around 1300, from whence later originated the liquid compass and the gyrocompass. Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (2560 × 1920 pixel, file size: 1. ... a compass In drafting, a compass (or pair of compasses) is an instrument]] used by mathematicians and craftsmen in for drawing or inscribing a circle or arc. ... A compass is a navigational tool that indicates the direction to the magnetic poles. ... The magnetosphere shields the surface of the Earth from the charged particles of the solar wind. ... Magnetic field lines shown by iron filings Magnetostatics Electrodynamics Electrical Network Tensors in Relativity This box:      In physics, the magnetic field is a field that permeates space and which exerts a magnetic force on moving electric charges and magnetic dipoles. ... Table of geography, hydrography, and navigation, from the 1728 Cyclopaedia. ... Cardinal directions or cardinal points are the four principal directions or points of the compass, north, east, south and west. ... A marine chronometer is a timekeeper precise enough to be used as a portable time standard, used to determine longitude by means of celestial navigation. ... Longitude is the east-west geographic coordinate measurement most commonly utilized in cartography and global navigation. ... A sextant is a measuring instrument generally used to measure the angle of elevation of a celestial object above the horizon. ... This article is about the geographical term. ... Table of geography, hydrography, and navigation, from the 1728 Cyclopaedia. ... For other uses, see Europe (disambiguation). ...


A compass is a magnetic device using a needle to indicate the direction of the magnetic north of a planet's magnetosphere. Any instrument with a magnetized bar or needle turning freely upon a pivot and pointing in a northerly and southerly direction can be considered a compass. A compass dial is a small pocket compass with a sundial. A variation compass is a specific instrument of a delicate type of construction. It is used by observing variations of the needle. A gyrocompass or astrocompass, which does not depend on the earth's magnetic field for its operation, can also be used to find true north. Part of the Carta Marina of 1539 by Olaus Magnus, depicting the location of magnetic north vaguely conceived as Insula Magnetu[m] (Latin for Magnetic Island) off modern day Murmansk. ... A magnetosphere is the region around an astronomical object in which phenomena are dominated or organized by its magnetic field. ... Captain Nemo and Professor Aronnax contemplating measuring instruments in Twenty Thousand Leagues Under the Sea In physics and engineering, measurement is the activity of comparing physical quantities of real-world objects and events. ... A pivot is that on which something turns. ... Compass rose with north highlighted and at top Look up North in Wiktionary, the free dictionary. ... A compass rose with South highlighted South is most commonly a noun, adjective, or adverb indicating direction or geography. ... For other uses, see Sundial (disambiguation). ... This article is about gyrocompasses used on ships. ... An Astrocompass is a navigational tool for determining the direction of north through the positions of various astronomical bodies. ... True Pizza is a navigational term referring to the direction of the North Pole relative to the navigators position. ...

Contents

History of the navigational compass

Pre-history

Prior to the introduction of the compass, direction at sea was primarily determined by the position of celestial bodies. Navigation was supplemented in some places by the use of soundings. Difficulties arose where the sea was too deep for soundings and conditions were continually overcast or foggy. Thus the compass was not of the same utility everywhere. For example, the Arabs could generally rely on clear skies in navigating the Persian Gulf and the Indian Ocean (as well as the predictable nature of the monsoons). This may explain in part their relatively late adoption of the compass. Mariners in the relatively shallow Baltic made extensive use of soundings. The astrolabe, originally invented in the Hellenistic world, was significantly improved upon by later medieval Muslim astronomers and navigators who used it to aid in navigation. A sounding line or lead line is a length of thin rope with a weight, generally of lead at its end. ... Map of the Persian Gulf. ... For other uses, see Monsoon (disambiguation). ... For other uses, see Baltic (disambiguation). ... A 16th century astrolabe. ... The term Hellenistic (derived from Héllēn, the Greeks traditional self-described ethnic name) was established by the German historian Johann Gustav Droysen to refer to the spreading of Greek culture over the non-Greek people that were conquered by Alexander the Great. ... This is a sub-article of Islamic science and astronomy. ... During the Islamic Golden Age, usually dated from the 8th century to the 13th century,[1] engineers, scholars and traders of the Islamic world contributed enormously to the arts, agriculture, economics, industry, literature, navigation, philosophy, sciences, and technology, both by preserving and building upon earlier traditions and by adding many...


Mesoamerica

The find of an Olmec hematite artifact, fitted with a sighting mark and found in experiment as fully operational as a compass, has led the American astronomer John Carlson after radiocarbon dating to conclude that "the Olmec may have discovered and used the geomagnetic lodestone compass earlier than 1000 BC".[1] Carlson suggests that the Olmecs may have used such devices for directional orientation of the dwellings of the living and the interments of the dead.[2] Monument 1, one of the four Olmec colossal heads at La Venta. ... Hematite, also spelled haematite, is the mineral form of Iron(III) oxide, (Fe2O3), one of several iron oxides. ... Radiocarbon dating is a radiometric dating method that uses the naturally occurring isotope carbon-14 (14C) to determine the age of carbonaceous materials up to about 60,000 years. ...


Needle-and-bowl device

By rubbing a needle on silk, the needle becomes magnetized and when placed in a straw and put in a puddle of water it becomes a compass. This device was universally used as a compass until the introduction of the box-like compass with a pivoting 'dry' needle around 1300.


China

Due to disagreement as to when the compass was invented, it may be appropriate to list some noteworthy Chinese literary references offered as possible evidence for its antiquity, in chronological order:

A Han Dynasty (206 BC – 220 AD) ladle-and-basin lodestone south-pointing compass.
A Han Dynasty (206 BC – 220 AD) ladle-and-basin lodestone south-pointing compass.
  • The earliest Chinese literature reference to magnetism lies in a 4th century BC book called Book of the Devil Valley Master (鬼谷子): "The lodestone makes iron come or it attracts it."[3]
  • The first mention of the magnetic attraction of a needle is to be found in a Chinese work composed between 20 and 100 AD (Lun-heng): "A lodestone attracts a needle."[4] In 1948, the scholar Wang Tchen-touo tentatively constructed a 'compass' in the form of south-indicating spoon on the basis of this text. However, it should be noted that "there is no explicit mention of a magnet in the Louen-heng" and that "beforehand it needs to assume some hypotheses to arrive at such a conclusion".[5]
  • The earliest reference to a specific magnetic direction finder device is recorded in a Song Dynasty book dated to 1040-44. Here we find a description of an iron "south-pointing fish" floating in a bowl of water, aligning itself to the south. The device is recommended as a means of orientation "in the obscurity of the night." As Li Shu-hua pointed out in 1954, there was no mention of a use for navigation, nor how the fish was magnetized.[6] However, in Needham's publication Science and Civilization in China: Volume 4, Part 1 in 1962, he proved otherwise, as Wang Chenduo had pointed out. The Wujing Zongyao (武经总要, "Collection of the Most Important Military Techniques") of 1044 stated: "When troops encountered gloomy weather or dark nights, and the directions of space could not be distinguished...they made use of the [mechanical] south-pointing carriage, or the south-pointing fish.[7] This was achieved by heating of metal (especially if steel), known today as thermo-remanence, and would have been capable of producing a weak state of magnetization.[7]
  • The first incontestable reference to a magnetized needle in Chinese literature appears as early as 1086 AD.[8] The Dream Pool Essays, written by the Song Dynasty polymath scientist Shen Kuo, contained a detailed description of how geomancers magnetized a needle by rubbing its tip with lodestone, and hung the magnetic needle with one single strain of silk with a bit of wax attached to the center of the needle. Shen Kuo pointed out that a needle prepared this way sometimes pointed south, sometimes north.
  • The earliest recorded actual use of a magnetized needle for navigational purposes then is to be found in Zhu Yu's book Pingzhou Table Talks (萍洲可談; Pingzhou Ketan) of AD 1119 (written from 1111 to 1117 AD): The navigator knows the geography, he watches the stars at night, watches the sun at day; when it is dark and cloudy, he watches the compass. This of course would have been aided by Shen Kuo's discovery (while working as the court's head astronomer) of the concept of true north: magnetic declination towards the magnetic north pole away from the polestar.

Thus, the first clear instance of a magnetic direction finder, a compass, appeared ca. 1044. However, it should be pointed out that the compass remained in use by the Chinese in the form of a magnetic needle floating in a bowl of water.[9] Image File history File links Metadata Size of this preview: 800 × 534 pixelsFull resolution (1024 × 683 pixel, file size: 356 KB, MIME type: image/jpeg) Model Si Nan of Han Dynasty File historyClick on a date/time to view the file as it appeared at that time. ... Image File history File links Metadata Size of this preview: 800 × 534 pixelsFull resolution (1024 × 683 pixel, file size: 356 KB, MIME type: image/jpeg) Model Si Nan of Han Dynasty File historyClick on a date/time to view the file as it appeared at that time. ... Han Dynasty in 87 BC Capital Changan (202 BC–9 AD) Luoyang (25 AD–190 AD) Language(s) Chinese Religion Taoism, Confucianism Government Monarchy History  - Establishment 206 BC  - Battle of Gaixia; Han rule of China begins 202 BC  - Interruption of Han rule 9 - 24  - Abdication to Cao Wei 220... Magnetite Lodestone or loadstone refers to either: Magnetite, a magnetic mineral form of iron(II), iron(III) oxide Fe3O4, one of several iron oxides. ... Chinese literature spans back thousands of years, from the earliest recorded dynastic court archives to the matured fictional novel arising in the medieval period to entertain the masses of literate Chinese. ... The 4th century BC started the first day of 400 BC and ended the last day of 301 BC. It is considered part of the Classical era, epoch, or historical period. ... Magnetite Lodestone or loadstone refers to either: Magnetite, a magnetic mineral form of iron(II), iron(III) oxide Fe3O4, one of several iron oxides. ... For other uses, see Iron (disambiguation). ... Northern Song in 1111 AD Capital Bianjing (汴京) (960–1127) Linan (臨安) (1127–1276) Language(s) Chinese Religion Buddhism, Taoism, Confucianism Government Monarchy Emperor  - 960–976 Emperor Taizu  - 1126–1127 Emperor Qinzong  - 1127–1162 Emperor Gaozong  - 1278–1279 Emperor Bing History  - Zhao Kuangyin taking over the throne of the Later Zhou... A Chinese Song Dynasty naval river ship with a Xuanfeng traction-trebuchet catapult on its top deck, taken from an illustration of the Wujing Zongyao. ... South Pointing Chariot (replica) The South Pointing Chariot (Zhi Nan Che 指南車) is widely regarded as the most complex geared mechanism of the ancient Chinese civilization, and was continually used throughout the medieval period as well. ... Shen Kuo (沈括) (1031-1095 AD) The Dream Pool Essays (Pinyin: Meng Xi Bi Tan; Wade-Giles: Meng Chi Pi Tan Chinese: 梦溪笔谈) was an extensive book written by the polymath Chinese scientist and statesman Shen Kuo (1031-1095) by 1088 AD, during the Song Dynasty (960-1279) of China. ... Northern Song in 1111 AD Capital Bianjing (汴京) (960–1127) Linan (臨安) (1127–1276) Language(s) Chinese Religion Buddhism, Taoism, Confucianism Government Monarchy Emperor  - 960–976 Emperor Taizu  - 1126–1127 Emperor Qinzong  - 1127–1162 Emperor Gaozong  - 1278–1279 Emperor Bing History  - Zhao Kuangyin taking over the throne of the Later Zhou... Leonardo da Vinci, a polymath, is seen as the epitome of the related term, Renaissance Man A polymath (Greek polymathÄ“s, πολυμαθής, having learned much)[1][2] is a person with encyclopedic, broad, or varied knowledge or learning. ... This is a Chinese name; the family name is Shen Shen Kuo or Shen Kua (Chinese: ; pinyin: ) (1031–1095) was a polymathic Chinese scientist and statesman of the Song Dynasty (960–1279). ... Geomancy (from the Latin geo, Earth, mancy prophecy) is a method of divination to interpret markings on the ground or how handfuls of dirt land when you toss them. ... A wall clock, with three dials A dial is generally a flat surface, circular or rectangular, with numbers or similar markings on it, used for displaying the setting or output of a timepiece, radio or measuring instrument. ... For other uses of this word, see Silk (disambiguation). ... candle wax This page is about the substance. ... Zhu Yu (Chinese: ; Wade-Giles: Chu Yü) was an author of the Chinese Song Dynasty (960-1279 AD). ... Events February 2 - Callixtus II becomes Pope August 20 - Henry I of England routes Louis VI at the Battle of Bremule. ... An astronomer or astrophysicist is a person whose area of interest is astronomy or astrophysics. ... True Pizza is a navigational term referring to the direction of the North Pole relative to the navigators position. ... This is about the geographic meaning of North Pole. ... This article is in need of attention. ...


According to Needham, the Chinese in the Song Dynasty and continuing Yuan Dynasty did make use of a dry compass, although this type never became as widely used in China as the wet compass.[10] Evidence of this is found in the Shilinguangji ('Guide Through the Forest of Affairs'), first published in 1325 by Chen Yuanjing, although its compilation had taken place between 1100 and 1250 AD.[10] The dry compass in China was a dry suspension compass, a wooden frame crafted in the shape of a turtle hung upside down by a board, with the loadstone sealed in by wax, and if rotated, the needle at the tail would always point in the northern cardinal direction.[10] Although the 14th century European compass-card in box frame and dry pivot needle was adopted in China after its use was taken by Japanese pirates in the 16th century (who had in turn learned of it from Europeans),[11] the Chinese design of the suspended dry compass persisted in use well into the 18th century.[12] Northern Song in 1111 AD Capital Bianjing (汴京) (960–1127) Linan (臨安) (1127–1276) Language(s) Chinese Religion Buddhism, Taoism, Confucianism Government Monarchy Emperor  - 960–976 Emperor Taizu  - 1126–1127 Emperor Qinzong  - 1127–1162 Emperor Gaozong  - 1278–1279 Emperor Bing History  - Zhao Kuangyin taking over the throne of the Later Zhou... Capital Dadu Language(s) Mongolian Chinese Government Monarchy Emperor  - 1260-1294 Kublai Khan  - 1333-1370 (Cont. ...


However, according to Kreutz there is only a single Chinese reference to a dry-mounted needle (built into a pivoted wooden tortoise) which is dated to between 1150 and 1250, but there is no indication that Chinese mariners ever used anything but the floating needle in a bowl until the 16th-century European contacts.[13]


Additionally, it must be pointed out that, unlike Needham, other experts on the history of the compass make no mention of an indigenous dry compass in China and reserve the term for the European form which became later worldwide standard.[14][15][16]


Later developments in China

Diagram of a Ming Dynasty mariner's compass
Diagram of a Ming Dynasty mariner's compass
  • The first recorded use of a 48 position mariner's compass on sea navigation was noted in a book titled “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 sailed 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.[17]
  • Zheng He's Navigation Map, also known as "The Mao Kun Map", contains a large amount of detail "needle records" of Zheng He's travel.[18]
  • A pilot's compass handbook titled Shun Feng Xiang Song (Fair Winds for Escort) in the Oxford Bodleian Library contains great details about the use of compass in navigation.

Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Zhou Daguan (1266-1346 A.D.) was a Chinese diplomat under the Emperor Chengzong of Yuan China. ... Wenzhou (Simplified Chinese: 温州; Traditional Chinese: 溫州; Hanyu Pinyin: ) is a prefecture-level city with a population of 873,000 in southeastern Zhejiang province, Peoples Republic of China. ... Face-tower of the South Gate, showing Avalokiteshvara Bayon temple, Angkor Thom The Terrace of the Leper King, showing apsara Angkor Thom was the fortified inner royal city built by Jayavarman VII (1181 - 1220?), Buddhist king of the Khmer Empire, at the end of the 12th Century, after Angkor had... Baria Qureshi was born December 3, 1988, in Queen Marys Hospital, Roehampton, London. ... A modern illustration of Zheng He, by an unidentified artist. ... Entrance to the Library, with the coats-of-arms of several Oxford colleges The Bodleian Library, the main research library of the University of Oxford, is one of the oldest libraries in Europe, and in England is second in size only to the British Library. ...

Question of diffusion

Navigational sailor's compass rose.
Navigational sailor's compass rose.

There is much debate on what happened to the compass after its first appearance with the Chinese. Different theories include: A mariners compass © Public Domain Davis, John. ... A mariners compass © Public Domain Davis, John. ... This article is about maritime crew. ...

  • Travel of the compass from China to the Middle East via the Silk Road, and then to Europe.
  • Direct transfer of the compass from China to Europe, and then later from China or Europe to the Middle East.
  • Independent creation of the compass in Europe, and thereafter its transfer from China or Europe to the Middle East.

The latter two are supported by evidence of the earlier mentioning of the compass in European works rather than Arabic. The first European mention of a magnetized needle and its use among sailors occurs in Alexander Neckam's De naturis rerum (On the Natures of Things), probably written in Paris in 1190.[19] Other evidence for this includes the Arabic word for "Compass" (al-konbas), possibly being a derivation of the old Italian word for compass. A map showing countries commonly considered to be part of the Middle East The Middle East is a region comprising the lands around the southern and eastern parts of the Mediterranean Sea, a territory that extends from the eastern Mediterranean Sea to the Persian Gulf. ... The Silk Road extending from Southern Europe through Arabia, Egypt, Persia, India till it reaches China. ... For other uses, see Europe (disambiguation). ... A map showing countries commonly considered to be part of the Middle East The Middle East is a region comprising the lands around the southern and eastern parts of the Mediterranean Sea, a territory that extends from the eastern Mediterranean Sea to the Persian Gulf. ... For other uses, see Europe (disambiguation). ... A map showing countries commonly considered to be part of the Middle East The Middle East is a region comprising the lands around the southern and eastern parts of the Mediterranean Sea, a territory that extends from the eastern Mediterranean Sea to the Persian Gulf. ... Alexander of Neckam (sometimes spelled Necham or Nequam) (September 8, 1157 – 1217), was an English scholar and teacher. ... This article is about the capital of France. ... Arabic can mean: From or related to Arabia From or related to the Arabs The Arabic language; see also Arabic grammar The Arabic alphabet, used for expressing the languages of Arabic, Persian, Malay ( Jawi), Kurdish, Panjabi, Pashto, Sindhi and Urdu, among others. ...


In the Arab world, the earliest reference comes in The Book of the Merchants' Treasure, written by one Baylak al-Kibjaki in Cairo about 1282.[20] Since the author describes having witnessed the use of a compass on a ship trip some forty years earlier, some scholars are inclined to antedate its first appearance accordingly. There is also a slightly earlier non-Mediterranean Muslim reference to an iron fish-like compass in a Persian talebook from 1232.[21].


Question of independent European invention

Pivoting compass needle in a 14th century copy of 'Epistola de magnete' of Peter Peregrinus (1269)
Pivoting compass needle in a 14th century copy of 'Epistola de magnete' of Peter Peregrinus (1269)

There have been various arguments put forward whether the European compass was an independent invention or not: Image File history File links Download high-resolution version (1055x1101, 762 KB) Darstellung eines Kompasses. ... Image File history File links Download high-resolution version (1055x1101, 762 KB) Darstellung eines Kompasses. ... Pivoting compass needle in a 14th century handcopy of Peters Epistola de magnete (1269) Peter of Maricourt (Peter Peregrinus of Maricourt;[1] French Pierre Pèlerin de Maricourt; Latin Petrus Peregrinus de Maharncuria) (fl. ...


Arguments pro independent invention:

  • The navigational needle in Europe points invariably north, whereas nearly always south in China.
  • The European compass showed from the beginning sixteen basic divisions, not twenty-four as in China.[22]
  • The apparent failure of the Arabs to function as possible intermediaries between East and West due to the earlier recorded appearance of the compass in Europe (1190)[19] than in the Muslim world (1232, 1242, or 1282).[20] [21]
  • The fact that the European compass rather soon developed from the magnetized needle (1190)[19] into the dry compass (by 1300)[23] may indicate that the prior invention of the needle-and-bowl device was also done independently.

Arguments contra independent invention:

  • The temporal priority of the Chinese navigational compass (1117) as opposed to the European (1190).[19]
  • The common shape of the early compass as a magnetized needle floating in a bowl of water.[24]

Impact in the Mediterranean

In the Mediterranean, the introduction of the mariner's compass, at first only known as a magnetized pointer floating in a bowl of water[25], went hand in hand with improvements in dead reckoning methods, and the development of Portolan charts, leading to more navigation during winter months in the second half of the 13th century.[26] While the practice from ancient times had been to curtail sea travel between October and April, due in part to the lack of dependable clear skies during the Mediterranean winter, the prolongation of the sailing season resulted in a gradual, but sustained increase in shipping movement: By around 1290 the sailing season could start in late January or February, and end in December.[27] The additional few months were of considerable economic importance. For instance, it enabled Venetian convoys to make two round trips a year to the Levant, instead of one.[28] Dead reckoning (DR) is the process of estimating ones current position based upon a previously determined position, or fix, and advancing that position based upon measured velocity, time, heading, as well as the effect of currents or wind. ... A Japanese portolan chart of the Indian Ocean, early 17th century A portolan (derived from the Latin word portus, port) is an early modern European navigation chart, dating from the thirteenth century or later, in manuscript, usually with rhumb lines, shorelines and place names. ... (12th century - 13th century - 14th century - other centuries) As a means of recording the passage of time, the 13th century was that century which lasted from 1201 to 1300. ... For other uses, see Venice (disambiguation). ... The Levant The Levant (IPA: ) is an imprecise geographical term historically referring to a large area in the Middle East south of the Taurus Mountains, bounded by the Mediterranean Sea on the west, and by the northern Arabian Desert and Upper Mesopotamia to the east. ...


At the same time, traffic between the Mediterranean and northern Europe also increased, with first evidence of direct commercial voyages from the Mediterranean into the English Channel coming in the closing decades of the 13th century, and one factor may be that the compass made traversal of the Bay of Biscay safer and easier.[29] Map of the Bay of Biscay. ...


Although critics like Kreutz feels that it was later in 1410 that anyone really started steering by compass. [30]


Mining

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 determing tunneling and defining the claims of the various mining companies as early as the 13th century.[31] In the second half of the 15th century, the compass belonged to the standard equipment of Tyrolian miners, and shortly afterwards a first detailed treatise dealing with the underground use of compasses was published by the German miner Rülein von Calw (1463-1525).[32] Tuscany (Italian Toscana) is a region in central Italy, bordering on Latium to the south, Umbria to the east, Emilia-Romagna and Liguria to the north, and the Tyrrhenian Sea to the west. ... Country Italy Region Tuscany Province Massa-Carrara (MS) Mayor Fabrizio Neri (since May 2003) Elevation 65 m Area 94 km² Population  - Total 66,097  - Density 703/km² Time zone CET, UTC+1 Coordinates Gentilic Massesi Dialing code 0585 Postal code 54100 Patron St. ... Coat of arms of the Counts of Tyrol Austria-Hungary in 1914, showing Tirol–Vorarlberg as the left-most province, coloured cream Capital Meran (Merano), until 1848 Government Principality Historical era Middle Ages  - Created County 1140  - Bequeathed to Habsburgs 1363 or 1369  - Joined Council of Princes 1582  - Trent, Tyrol and...


Dry compass

The familiar dry compass was invented in Europe around 1300. The true mariner's compass consists of three elements: A freely pivoting needle on a pin enclosed in a little box with a glass cover and a wind rose, whereby "the wind rose or compass card is attached to a magnetized needle in such a manner that when placed on a pivot in a box fastened in line with the keel of the ship the card would turn as the ship changed direction, indicating always what course the ship was on".[33] While pivoting needles in glass boxes had already been described by the French scholar Peter Peregrinus in 1269,[34] there is an inclination to honour tradition and credit Flavio Gioja (fl. 1302), an Italian marine pilot from Amalfi, with perfecting the sailor's compass by suspending its needle over a compass card, giving thus the compass its familiar appearance.[23] Such a compass with the needle attached to a rotating card is also described in a commentary on Dante's Divine Comedy from 1380, while an earlier source refers to a portable compass in a box (1318),[35] supporting the notion that the dry compass was known in Europe by then.[36] Pivoting compass needle in a 14th century handcopy of Peters Epistola de magnete (1269) Peter of Maricourt (Peter Peregrinus of Maricourt;[1] French Pierre Pèlerin de Maricourt; Latin Petrus Peregrinus de Maharncuria) (fl. ... Flavio Gioja, Italian inventor (fl. ... Events July 11 - Battle of the Golden Spurs (Guldensporenslag in Dutch), major victory of Flanders over the French occupier. ... Signal flag H(otel) - Pilot on Board A harbour pilot guides ships through the narrow, shallow and dangerous coastal waters between a harbour and the open sea. ... Amalfi is a town and commune in the province of Salerno, in the region of Campania, Italy, on the Gulf of Salerno, 24 miles southeast of Naples. ... DANTE is also a digital audio network. ... Dante shown holding a copy of The Divine Comedy, next to the entrance to Hell, the seven terraces of Mount Purgatory and the city of Florence, in Michelinos fresco. ...


Liquid compass

In 1936 Tuomas Vohlonen invented the first successful portable liquid-filled compass designed for individual use.[37] and i do the cha cha like a sissie girl. Trains go toot toot Tuomas Vohlonen (1878–1939) was a famous Finnish inventor. ...


Construction of a simple compass

A magnetic rod is required when constructing a compass. This can be created by aligning an iron or steel rod with Earth's magnetic field and then tempering or striking it. However, this method produces only a weak magnet so other methods are preferred. This magnetised rod (or magnetic needle) is then placed on a low friction surface to allow it to freely pivot to align itself with the magnetic field. It is then labeled so the user can distinguish the north-pointing from the south-pointing end; in modern convention the north end is typically marked in some way, often by being painted red.


Modern compasses

Liquid filled lensatic compass
Liquid filled lensatic compass

Modern hand-held navigational compasses use a magnetized needle or dial inside a fluid-filled (oil, kerosene, or alcohol is common) capsule; the fluid causes the needle to stop quickly rather than oscillate back and forth around magnetic north. Most modern recreational and military compasses integrate a protractor with the compass, using a separate magnetized needle. In this design the rotating capsule containing the magnetized needle is fitted with orienting lines and an outlined orienting arrow, then mounted in a transparent baseplate containing a direction-of-travel (DOT) indicator for use in taking bearings directly from a map. Other features found on some modern handheld compasses are map and romer scales for measuring distances and plotting positions on maps, luminous markings or bezels for use at night or poor light, various sighting mechanisms (mirror, prism, etc.) for taking bearings of distant objects with greater precision, 'global' needles for use in differing hemispheres, adjustable declination for obtaining instant true bearings without resort to arithmetic, and devices such as inclinometers for measuring gradients. Download high resolution version (1320x1467, 118 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (1320x1467, 118 KB) Wikipedia does not have an article with this exact name. ... The term protractor is used both in technics and surgery. ...


The military forces of a few nations, notably the United States Army, continue to utilize older lensatic card compass designs with magnetized compass dials instead of needles. A lensatic card compass permits reading the bearing off of the compass card with only a slight downward glance from the sights (see photo), but requires a separate protractor for use with a map. The official U.S. military lensatic compass does not use fluid to dampen needle swing, but rather electromagnetic induction. A 'deep-well' design is used to allow the compass to be used globally with little or no effect in accuracy caused by a tilting compass dial. As induction forces provide less damping than fluid-filled designs, a needle lock is fitted to the compass to reduce wear, operated by the folding action of the rear sight/lens holder. The use of air-filled induction compasses has declined over the years, as they may become inoperative or inaccurate in freezing temperatures or humid environments. For magnetic induction, see Magnetic field. ...


A range of specialty compasses would include a Qibla compass which is used by Muslims to show the direction to Mecca for prayers. Similarly a Jerusalem compass [38] is used by Jews to point the direction of Jerusalem for prayers. A qibla compass or qiblih compass (sometimes also called qibla/qiblih indicator) is a modified compass designed to indicate the direction of prayer. ...


Other specialty compasses include the optical or prismatic hand-bearing compass, often used by surveyors, cave explorers, or mariners. This compass uses an oil-filled capsule and magnetized compass dial with an integral optical or prismatic sight, often fitted with built-in photoluminescent or battery-powered illumination. Using the optical or prism sight, such compasses can be read with extreme accuracy when taking bearings to an object, often to fractions of a degree. Most of these compasses are designed for heavy-duty use, with solid metal housings, and many are fitted for tripod mounting for additional accuracy.


Mariner's compasses can have two or more magnetic needles permanently attached to a compass card. These move freely on a pivot. A lubber line, which can be a marking on the compass bowl or a small fixed needle indicates the ship's heading on the compass card.


Traditionally the card is divided into thirty-two points (known as rhumbs), although modern compasses are marked in degrees rather than cardinal points. The glass-covered box (or bowl) contains a suspended gimbal within a binnacle. This preserves the horizontal position. This article is about the material. ... A gimbal is a mechanical device that allows the rotation of an object in multiple dimensions. ... Binnacle (before 18th century bittacle, through Span. ...


Large ships typically rely on a gyrocompass, using the more reliable magnetic compass for back-up. Increasingly, electronic fluxgate compasses are used on smaller vessels. However compasses are widely in use as they can be small, use simple technology, comparatively cheap, often easier to use than GPS, require no energy supply and unlike GPS are not affected by objects e.g trees that can block the reception of electronic signals. This article is about gyrocompasses used on ships. ... Fluxgate Compass The basic fluxgate compass is a simple electromagnetic device that employs two small coils of wire to directly sense the horizontal component of the earths magnetic field. ...


Some modern military compasses, like the SandY-183 (the one pictured) contains the radioactive material Tritium (3H) and a combination of Phosphorous. The SandY-183 contained 120mCi (millicuries) of tritium. The purpose of the tritium and phosphorous is to power the illumination for the compass. This illumination works off a chemical reaction, not requiring the compass to be "recharged" through sunlight or artificial light. The name SandY-183 is derived from the name of the company, Stocker and Yale (SandY). Tritium (symbol T or ³H) is a radioactive isotope of hydrogen. ...


Solid state compasses

Small compasses found in clocks, cell phones (e.g. the Nokia 5140i) and other electronic gear are solid-state devices usually built out of two or three magnetic field sensors that provide data for a microprocessor. Using trigonometry the correct heading relative to the compass is calculated. Motorola T2288 mobile phone A mobile phone is a portable electronic device which behaves as a normal telephone whilst being able to move over a wide area (compare cordless phone which acts as a telephone only within a limited range). ... The term solid state was introduced in the 1960s to describe electronic devices whose circuits contained neither vacuum tubes nor mechanical devices such as relays, as transistors replaced vacuum tubes in most consumer electronics. ... Wikibooks has a book on the topic of Trigonometry All of the trigonometric functions of an angle θ can be constructed geometrically in terms of a unit circle centered at O. Trigonometry (from Greek trigōnon triangle + metron measure[1]), informally called trig, is a branch of mathematics that deals with...


Often, the device is a discrete component which outputs either a digital or analog signal proportional to its orientation. This signal is interpreted by a controller or microprocessor and used either internally, or sent to a display unit. An example implementation, including parts list and circuit schematics, shows one design of such electronics. The sensor uses precision magnetics and highly calibrated internal electronics to measure the response of the device to the Earth's magnetic field. The electrical signal is then processed or digitized. It has been suggested that this article or section be merged with embedded microprocessor. ... A microprocessor is a programmable digital electronic component that incorporates the functions of a central processing unit (CPU) on a single semiconducting integrated circuit (IC). ... A digital circuit that acts as a binary clock, hand-wired on a series of breadboards Digital electronics are electronics systems that use digital signals. ...


Bearing compass

Bearing compass (18th century).
Bearing compass (18th century).

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. Image File history File links Metadata Size of this preview: 471 × 599 pixelsFull resolution‎ (1,825 × 2,320 pixels, file size: 2. ... Image File history File links Metadata Size of this preview: 471 × 599 pixelsFull resolution‎ (1,825 × 2,320 pixels, file size: 2. ...

  • West Marine: How to use a hand bearing compass

Compass correction

Main article: Magnetic deviation
A binnacle containing a ship's steering compass, with the two iron balls which correct the effects of ferromagnetic materials
A binnacle containing a ship's steering compass, with the two iron balls which correct the effects of ferromagnetic materials

Like any magnetic device, compasses are affected by nearby ferrous materials as well as by strong local electromagnetic forces. Compasses used for wilderness land navigation should never be used in close proximity to ferrous metal objects or electromagnetic fields (batteries, car bonnets, i do the cha cha like a sissie girl.engines go toot toot, steel pitons, wristwatches, etc.) Magnetic deviation is the error induced in a compass by local magnetic fields, which must be allowed for if accurate bearings are to be calculated. ... Image File history File links Download high resolution version (1920x2560, 248 KB) Photograph by Rama File links The following pages link to this file: Compass ... Image File history File links Download high resolution version (1920x2560, 248 KB) Photograph by Rama File links The following pages link to this file: Compass ... Binnacle (before 18th century bittacle, through Span. ... Ferromagnetism is the phenomenon by which materials, such as iron, in an external magnetic field become magnetized and remain magnetized for a period after the material is no longer in the field. ...


Compasses used in or near trucks, cars or other mechanized vehicles are particularly difficult to use accurately, even when corrected for deviation by the use of built-in magnets or other devices. Large amounts of ferrous metal combined with the on-and-off electrical fields caused by the vehicle's ignition and charging systems generally result in significant compass errors.


At sea, a ship's compass must also be corrected for errors, called deviation, caused by iron and steel in its structure and equipment. The ship is swung, that is rotated about a fixed point while its heading is noted by alignment with fixed points on the shore. A compass deviation card is prepared so that the navigator can convert between compass and magnetic headings. The compass can be corrected in three ways. First the lubber line can be adjusted so that it is aligned with the direction in which the ship travels, then the effects of permanent magnets can be corrected for by small magnets fitted within the case of the compass. The effect of ferromagnetic materials in the compass's environment can be corrected by two iron balls mounted on either side of the compass binacle. The coefficient a0 representing the error in the lubber line, while a1,b1 the ferromagnetic effects and a2,b2 the non-ferromagnetic component. Magnetic deviation is the error induced in a compass by local magnetic fields, which must be allowed for if accurate bearings are to be calculated. ... For other uses, see Iron (disambiguation). ... For other uses, see Steel (disambiguation). ... A lubber line is a fixed-line displayed on a compass binnacle or radar Plan Position Indicator display pointing towards the front of the ship or aircraft and corresponding to the crafts centreline. ... Ferromagnetism is the phenomenon by which materials, such as iron, in an external magnetic field become magnetized and remain magnetized for a period after the material is no longer in the field. ...


Fluxgate compasses can be calibrated automatically, and can also be programmed with the correct local compass variation so as to indicate the true heading.


Using a compass

Turning the compass scale on the map (D - the local magnetic declination)
Turning the compass scale on the map (D - the local magnetic declination)
When the needle is aligned with and superimposed over the outlined orienting arrow on the bottom of the capsule, the degree figure on the compass ring at the direction-of-travel (DOT) indicator gives the magnetic bearing to the target (mountain).
When the needle is aligned with and superimposed over the outlined orienting arrow on the bottom of the capsule, the degree figure on the compass ring at the direction-of-travel (DOT) indicator gives the magnetic bearing to the target (mountain).

The simplest way of using a compass is to know that the arrow always points in the same direction, magnetic North, which is roughly similar to true north. Except in areas of extreme magnetic declination variance (20 degrees or more), this is enough to protect from walking in a substantially different or even opposite direction than expected over short distances, provided the terrain is fairly flat and visibility is not impaired. In fact, by carefully recording distances (time or paces) and magnetic bearings traveled, one can plot a course and return to one's starting point using the compass alone. Image File history File links Download high-resolution version (2412x1600, 504 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Compass ... Image File history File links Download high-resolution version (2412x1600, 504 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Compass ... Image File history File links Download high-resolution version (2140x2060, 459 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Compass ... Image File history File links Download high-resolution version (2140x2060, 459 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Compass ...


However, compass navigation used in conjunction with a map (terrain association) requires a different compass method. To take a map bearing or true bearing (a bearing taken in reference to true, not magnetic north) to a destination with a protractor compass, the edge of the compass is placed on the map so that it connects the current location with the desired destination (some sources recommend physically drawing a line). The orienting lines in the base of the compass dial are then rotated to align with actual or true north by aligning them with a marked line of longitude (or the vertical margin of the map), ignoring the compass needle entirely. The resulting true bearing or map bearing may then be read at the degree indicator or direction-of-travel (DOT) line, which may be followed as an azimuth (course) to the destination. If a magnetic north bearing or compass bearing is desired, the compass must be adjusted by the amount of magnetic declination before using the bearing so that both map and compass are in agreement. In the given example, the large mountain in the second photo was selected as the target destination on the map. Taking a bearing with a protractor compass Sighting a bearing with a protractor compass The protractor compass is a type of compass commonly often used in hill walking, orienteering and other outdoor sports and pursuits. ...


The modern hand-held protractor compass always has an additional direction-of-travel (DOT) arrow or indicator inscribed on the baseplate. To check one's progress along a course or azimuth, or to ensure that the object in view is indeed the destination, a new compass reading may be taken to the target if visible (here, the large mountain). After pointing the DOT arrow on the baseplate at the target, the compass is oriented so that the needle is superimposed over the orienting arrow in the capsule. The resulting bearing indicated is the magnetic bearing to the target. Again, if one is using 'true' or map bearings, and the compass does not have preset, pre-adjusted declination, one must additionally add or subtract magnetic declination to convert the magnetic bearing into a true bearing. The exact value of the magnetic declination is place-dependent and varies over time, though declination is frequently given on the map itself or obtainable on-line from various sites. If not, any local walker club should know it. If the hiker has been following the correct path, the compass' corrected (true) indicated bearing should closely correspond to the true bearing previously obtained from the map. Taking a bearing with a protractor compass Sighting a bearing with a protractor compass The protractor compass is a type of compass commonly often used in hill walking, orienteering and other outdoor sports and pursuits. ... Magnetic declination. ...


This method is sometimes known as the Silva 1-2-3 System, after Silva Compass, manufacturers of the first protractor compasses. Silva compass, more commonly called Silva is an outdoors persuits company, most known for their high-grade compass and other navigational equipment including GPS tools, mapping software, and even create altimiters for aircraft. ...


A dynamic rotating draggable Silva compass is available online to practice setting compass and map bearings: http://geographyfieldwork.com/UsingCompass.htm

  • Literature [1]

Compass balancing

Because the Earth's magnetic field's inclination and intensity vary at different latitudes, compasses are often balanced during manufacture. Most manufacturers balance their compass needles for one of five zones, ranging from zone 1, covering most of the Northern Hemisphere, to zone 5 covering Australia and the southern oceans. This balancing prevents excessive dipping of one end of the needle which can cause the compass card to stick and give false readings. Suunto has recently introduced two-zone compasses that can be used in one entire hemisphere, and to a limited extent in another without significant loss of accuracy. Northern hemisphere highlighted in yellow. ... Suunto, based in Finland, is a company that produces and markets electronic measurement devices. ...


Some different compass systems:

Points of the compass

Main article: Boxing the compass

Originally, many compasses were marked only as to the direction of magnetic north, or to the four cardinal points (north, south, east, west). Later, mariners divided the compass card into thirty-two equally spaced points divided from the cardinal points. For a table of the thirty-two points, see compass points. A modern compass card. ... A modern compass card. ...


The 360-degree system later took hold, which is still in use today for civilian navigators. The degree dial spaces the compass markings with 360 equidistant points. Other nations adopted the 'grad' system, which spaces the dial into 400 grads or points.


Most military defense forces have adopted the 'mil' system, in which the compass dial is spaced into 6400 units (some nations use 6000) or 'mils' for additional precision when measuring angles, laying artillery, etc. The value to the military is that one mil subtends approximately one metre at a distance of one kilometer.


Former Warsaw Pact countries (Soviet Union, GDR etc.) used a 60° graduation, often counterclockwise (see picture of wrist compass). This is still in use in Russia. Not to be confused with the Warsaw Convention, which is an agreement about airlines financial liability and the Treaty of Warsaw (1970) between West Germany and the Peoples Republic of Poland. ... Disambiguation Page Global Depositary Receipt East Germany ...


See also

For other persons named William Gilbert, see William Gilbert (disambiguation). ... Azimuth is the horizontal component of a direction (compass direction), measured around the horizon, from the north toward the east (i. ... This page meets Wikipedias criteria for speedy deletion. ... A standard Brunton Pocket Transit (unfolded) A Brunton compass, properly known as the Brunton Pocket Transit, is a type of precision compass made by Brunton, Inc. ... Finding North using a watch: A watch can be used to find North. ... See Cartesian coordinate system or Coordinates (elementary mathematics) for a more elementary introduction to this topic. ... Pioneer bubble sextant used in conjunction with the EIC The Earth Inductor Compass was designed in 1924 by Morris Titterington at the Pioneer Instrument Company. ... Fluxgate Compass The basic fluxgate compass is a simple electromagnetic device that employs two small coils of wire to directly sense the horizontal component of the earths magnetic field. ... GPS redirects here. ... This article is about gyrocompasses used on ships. ... An inertial navigation system measures the position and altitude of a vehicle by measuring the accelerations and rotations applied to the systems inertial frame. ... There are very few or no other articles that link to this one. ... A pelorus or dumb compass, or a compass card (called a pelorus card) is a navigation tool without a directive element, suitably mounted and provided with vanes to permit observation of relative bearings, e. ... Taking a bearing with a protractor compass Sighting a bearing with a protractor compass The protractor compass is a type of compass commonly often used in hill walking, orienteering and other outdoor sports and pursuits. ... A radio direction finder, or RDF, is a device for finding the direction to a radio source. ... A radio direction finder, or RDF, is a device for finding the direction to a radio source. ... Silva compass, more commonly called Silva is an outdoors persuits company, most known for their high-grade compass and other navigational equipment including GPS tools, mapping software, and even create altimiters for aircraft. ... Suunto, based in Finland, is a company that produces and markets electronic measurement devices. ... Drawing of a circumferentor from the Cyclopaedia A circumferentor, or surveyors compass, is an instrument used in surveying to measure horizontal angles, now superseded by the theodolite. ... A Thumb compass is a type of orienteering compass commonly used in orienteering, a sport in which map reading and terrain association are paramount. ... A Thumb compass is a type of orienteering compass commonly used in orienteering, a sport in which map reading and terrain association are paramount. ...

Gallery

Notes

  1. ^ Carlson, p. 753–760
  2. ^ Carlson, p. 753–760
  3. ^ Li Shu-hua, p. 175
  4. ^ Li Shu-hua, p. 176
  5. ^ Li Shu-hua, p. 180
  6. ^ Li Shu-hua, p. 181
  7. ^ a b Needham, p. 252
  8. ^ Li Shu-hua, p. 182f.
  9. ^ Kreutz, p. 373
  10. ^ a b c Needham p. 255
  11. ^ Needham, p. 289.
  12. ^ Needham, p. 290
  13. ^ Kreutz, p. 373
  14. ^ Kreutz, p. 367–383
  15. ^ Lane
  16. ^ Li Shu-hua, p. 175-196
  17. ^ Zhou
  18. ^ Ma, Appendix 2
  19. ^ a b c d Kreutz, p. 368
  20. ^ a b Kreutz, p. 369
  21. ^ a b Kreutz, p. 370
  22. ^ Kreutz, p. 376
  23. ^ a b Lane, p. 616
  24. ^ Kreutz, p. 368f.
  25. ^ Kreutz, p. 368–369
  26. ^ Lane, p. 606f.
  27. ^ Lane, p. 608
  28. ^ Lane, p. 608 & 610
  29. ^ Lane, p. 608 & 613
  30. ^ Kreutz, p. 372–373
  31. ^ Ludwig and Schmidtchen, p. 62–64
  32. ^ Ludwig and Schmidtchen, p. 64
  33. ^ Lane, p. 615
  34. ^ Taylor
  35. ^ Kreutz, p. 374
  36. ^ Kreutz, p. 373
  37. ^ http://www.prh.fi/en/tietoaprhsta/innogalleria/vohlonen_takes_a_bearing.html
  38. ^ http://www.jewishsoftware.com/products/The_Incredible_Jerusalem_Compass_813.asp?bhcd2=1177746874

References

  • Admiralty, Great Britain (1915) Admiralty manual of navigation, 1914, Chapter XXV: "The Magnetic Compass (continued): the analysis and correction of the deviation", London : HMSO, 525 p.
  • Aczel, Amir D. (2001) The Riddle of the Compass: The Invention that Changed the World, 1st Ed., New York : Harcourt, ISBN 0-15-600753-3
  • Carlson, John B. (1975) "Lodestone Compass: Chinese or Olmec Primacy?: Multidisciplinary analysis of an Olmec hematite artifact from San Lorenzo, Veracruz, Mexico”, Science, 189 (4205 : 5 September), p. 753-760, DOI 10.1126/science.189.4205.753
  • Gies, Frances and Gies, Joseph (1994) Cathedral, Forge, and Waterwheel: Technology and Invention in the Middle Age, New York : HarperCollins, ISBN 0-06-016590-1
  • Gurney, Alan (2004) Compass: A Story of Exploration and Innovation, London : Norton, ISBN 0-393-32713-2
  • Kreutz, Barbara M. (1973) "Mediterranean Contributions to the Medieval Mariner's Compass", Technology and Culture, 14 (3: July), p. 367–383
  • Lane, Frederic C. (1963) "The Economic Meaning of the Invention of the Compass", The American Historical Review, 68 (3: April), p. 605–617
  • Li Shu-hua (1954) "Origine de la Boussole 11. Aimant et Boussole", Isis, 45 (2: July), p. 175–196
  • Ludwig, Karl-Heinz and Schmidtchen, Volker (1997) Metalle und Macht: 1000 bis 1600, Propyläen Technikgeschichte, Berlin : Propyläen-Verl., ISBN 3-549-05633-8
  • Ma, Huan (1997) Ying-yai sheng-lan [The overall survey of the ocean's shores (1433)], Feng, Ch'eng-chün (ed.) and Mills, J.V.G. (transl.), Bangkok : White Lotus Press, ISBN 974-8496-78-3
  • Needham, Joseph (1986) Science and civilisation in China, Vol. 4: "Physics and physical technology", Pt. 1: "Physics", Taipei: Caves Books, originally publ. by Cambridge University Press (1962), ISBN 0-521-05802-3
  • Needham, Joseph and Ronan, Colin A. (1986) The shorter Science and civilisation in China : an abridgement of Joseph Needham's original text, Vol. 3, Chapter 1: "Magnetism and Electricity", Cambridge University Press, ISBN 0-521-25272-5
  • Taylor, E.G.R. (1951) "The South-Pointing Needle", Imago Mundi, 8, p. 1–7
  • Williams, J.E.D. (1992) From Sails to Satellites: the origin and development of navigational science, Oxford University Press, ISBN 0-19-856387-6
  • Zhou, Daguan (2007) The customs of Cambodia, translated into English from the French version by Paul Pelliot of Zhou's Chinese original by J. Gilman d'Arcy Paul, Phnom Penh : Indochina Books, prev publ. by Bangkok : Siam Society (1993), ISBN 974-8298-25-6

Amir D. Aczel (b. ... DOI may refer to: Digital object identifier, a permanent identifier given to electronic documents 2,5-dimethoxy-4-iodoamphetamine, a hallucinogenic drug Declaration of Independence (when used as DoI), a proclamation of independence on the part of a nation This page concerning a three-letter acronym or abbreviation is a...

External links

Wikimedia Commons has media related to:
Compass
  • USGS Geomagnetism Program
  • Science Friday, "The Riddle of the Compass" (interview with Amir Aczel, first broadcast on NPR on May 31, 2002).
  • Paul J. Gans, The Medieval Technology Pages: Compass
  • The Tides By Sir William Thomson (Lord Kelvin)
  • Evening Lecture To The British Association At The Southampton Meeting on Friday, August 25, 1882 [2]. Refers to compass correction by Fourier series.
  • Arrick Robots. Robotics.com Example implementation for digital solid-state compass. ARobot Digital Compass App Note
  • How a tilt sensor works. David Pheifer [3]
  • The Gear Junkie - review of two orienteering thumb compasses
  • The good compass video - A video about important abilities a compass should have
  • BEWARE : The Brief History of the Bezard compass (1852 – 1971) on the Knowfuture site is a hoax. There is no such village in France. A Jewish family Bézard never existed. The Bezard compass was created by Johann von Bézard, an Austrian Colonel of French Huguenot origin and built by the LUFFT company in Germany whose factory was in Stuttgart. The BASF chemical company is situated on the river Rhine in Ludwigshafen. The whole story is beautiful but unfortunately untrue. Reliable information can be found on the following private sites:
    • Der Bézard-Kompaß (German)
    • La Original Bezard... (Italian).
  • Compass collector : rare old compasses (Bézard)!
  • The virtual compass museum - the greatest collection of compasses

  Results from FactBites:
 
Compass (379 words)
Compass has long been one of the most popular and powerful bookmark managers in the world.
With Compass, you'll be amazed how easy you can find and organize your bookmarks the way you want, and how easy you can integrate all bookmarks from different computers or different browsers.
When you use Compass as an outline editor, you will find Compass is even better than the programs that were created for that purpose.
Encyclopedia4U - Compass - Encyclopedia Article (937 words)
In math and drafting, device known as a compass (or pair of compasses) is used by mathematicians and craftsmen in geometry to draw or inscribe a circle or arc.
In carpentry, architecture, and shipbuilding, a compass is a curve (or bent) circular form.
A compass timber is a curved (or crooked) timber.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m