Divination Distillate

History of the compass

A reference to a magnetized needle as a

The book also notes that the people of the state of Zheng always knew their position by means of a south-pointer; some authors suggest that this refers to early use of the compass.

Alexander Neckamreported the use of a magnetic compass for the region of the English Channel in the textsDe utensilibusandDe naturis rerum,[46]written between 1187 and 1202, after he returned to England from France[47]and prior to entering the Augustinian abbey at Cirencester.[48]In his 1863 edition ofNeckamsDe naturis rerum, Thomas Wright provides a translation of the passage in which Neckam mentions sailors being guided by a compass needle:

In 1933Tuomas Vohlonen, a surveyor by profession, applied for a patent for a unique method of filling and sealing a lightweightcelluloidcompass housing or capsule with a petroleum distillate to dampen the needle and protect it from shock and wear caused by excessive motion.[96]Introduced in a wrist-mount model in 1936 as theSuuntoOyModel M-311, the new capsule design led directly to the lightweight liquid-filled field compasses of today.[96]

Model of aHan Dynasty(206 BC220 AD) south-indicating ladle or

Based on Krotser and Coes discovery of anartifact inMesoamericaradiocarbon datedto 14001000 BC, astronomer John Carlson has hypothesized that the Olmec might have used the geomagneticlodestoneearlier than 1000 BC forgeomancy, a method ofdivination, which if proven true, predates the Chinese use of magnetism forfeng shuiby a millennium.[10]Carlson speculates that the Olmecs used similar artifacts as a directional device for astronomical orgeomanticpurposes but does not suggest navigational usage. The artifact is part of a polishedhematitebar with a groove at one end, possibly used for sighting. Carlsons claims have been disputed by other scientific researchers, who have suggested that the artifact is actually a constituent piece of a decorative ornament and not a purposely built compass.[11]Several other hematite or magnetite artifacts have been found at pre-Columbian archaeological sites in Mexico and Guatemala.[12][13]

The Genius That Was China: East and West in the making of the modern world

(1565): 772782.doi10.1098/rstb.2010.0194PMC

Despite these advances, the liquid compass was not introduced generally into the Royal Navy until 1908. An early version developed by RN Captain Creak proved to be operational under heavy gunfire and seas, but was felt to lack navigational precision compared with the design by Lord Kelvin.[5][90]However, with ship and gun sizes continuously increasing, the advantages of the liquid compass over the Kelvin compass became unavoidably apparent to the Admiralty, and after widespread adoption by other navies, the liquid compass was generally adopted by the Royal Navy.[5]

Thecompasswas invented almost 2,000 years ago. The firstcompasseswere made oflodestone, a naturally magnetized ore of iron, inHan dynastyChina between 300 and 200 BC.The compass was later used for navigation by theSong Dynasty.Later compasses were made of iron needles, magnetized by striking them with a lodestone. Dry compasses begin appearing around 1300 inMedieval Europeand the MedievalIslamic world.This was replaced in the early 20th century by the liquid-filled magnetic compass.

Further information:Four Great InventionsList of Chinese inventions, andHistory of science and technology in China

in Chinese literature appears in 1088.

(Blue Bag Sea Angle Manual) from around the same period, also has an implicit description of magnetic declination. It has been argued that this knowledge of declination requires the use of the compass.

In the 15th century, the description given byIbn Majidwhile aligning the compass with the pole star indicates that he was aware ofmagnetic declination. An explicit value for the declination is given by ʿIzz al-Dn al-Wafʾ (fl. 1450s in Cairo).[4]

The Earths magnetic field: Its history, origin and planetary perspective

The earliest explicit recorded use of a magnetic compass for

The ships pilots are acquainted with the configuration of the coasts; at night they steer by the stars , and in the daytime by the sun. In dark weather they look at the south pointing needle

Prior to the introduction of the compass, geographical position and direction at sea were primarily determined by the sighting of landmarks, supplemented with the observation of the position of celestial bodies.[6]On cloudy days, the Vikings may have usedcordieriteor some otherbirefringent crystalto determine the suns direction andelevationfrom thepolarizationof daylight; their astronomical knowledge was sufficient to let them use this information to determine their proper heading.[7]The invention of the compass made it possible to determine a heading when the sky was overcast or foggy, and when landmarks were not in sight. This enabled mariners to navigate safely far from land, increasing sea trade, and contributing to theAge of Discovery.[8][9]

Late in the 13th century, theYemeniSultan anddescribed the use of the compass as aQiblaindicator to find the direction toMecca.[63]In a treatise aboutastrolabesandsundials, al-Ashraf includes several paragraphs on the construction of a compass bowl (ṭsa). He then uses the compass to determine the north point, themeridian(khaṭṭ niṣf al-nahr), and the Qibla. This is the first mention of a compass in a medieval Islamic scientific text and its earliest known use as a Qibla indicator, although al-Ashraf did not claim to be the first to use it for this purpose.[46][64]

Schmidl, Petra G. (2014-05-08). Compass. In Ibrahim Kalin.

(2): 6063.doi10.1109/MIE.2014.2316044.

Although the passage does not explicitly mention magnetism,

An iron needle, after having been in contact with the loadstone, turns itself always toward the northern star, which, like the axis of the firmament, remains immoveable, while the others follow their course, so that it is very necessary to those who navigate the sea.[52]

. Woodstock, New York: The Overlook Press. p.61.ISBN0-87951-397-7.

IEEE Industrial Electronics Magazine

The first recorded use of a 48 position mariners compass on sea navigation was noted inThe Customs of Cambodiaby Yuan Dynasty diplomatZhou Daguan, he described his 1296 voyage fromWenzhoutoAngkor Thomin 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 atBaria, the mariner took Kun Shen needle, or 52.5 degree SW.[43]Zheng Hes Navigation Map, also known as theMao Kun Map, contains a large amount of detail needle records ofZheng Hes expeditions.[44]

The first mention of a spoon, speculated to be a lodestone, observed

Pre modern Arabic sources refer to the compass using the termṭsa(lit. bowl) for the floating compass, orlat al-qiblah(qibla instrument) for a device used for orienting towards Mecca.[4]

Neckams clear understanding of the mariners compass in the late twelfth-century, and his description of its use in marine navigation, has cast doubt on whether the compass was, asProfessor Derk Boddehas argued, one of Chinas gifts to the West.[50]From Neckams description, some scholars have suggested it is not unlikely that the compass was also invented in Europe, independently of Eastern technologies.[51]This is further supported byJacques de Vitrys mention of the compass being used at sea in 1218, which indicates a broader knowledge of the compass and its uses in Medieval Northern Europe:

The earliest reference to a specific magnetic

Merrill, Ronald T.; McElhinny, Michael W. (1983).

according to Chen-Cheng Yih, the device described by Wang Chong has been widely considered to be the earliest form of the magnetic compass.

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 theBay of Biscaysafer and easier.[58]However, critics like Kreutz have suggested that it was later in 1410 that anyone really started steering by compass.[59]

(; Pingzhou Ketan) and dates from 1111 to 1117:

Chiu Thien Hsuan Nu Chhing Nang Hai Chio Ching

Philosophical Transactions of the Royal Society B

The earliestChinese literaturereference to

The sailors, moreover, as they sail over the sea, when in cloudy whether they can no longer profit by the light of the sun, or when the world is wrapped up in the darkness of the shades of night, and they are ignorant to what point of the compass their ships course is directed, they touch the magnet with a needle, which (the needle) is whirled round in a circle until, when its motion ceases, its point looks direct to the north.[49]

In 1269Petrus Peregrinusof Maricourt described a floating compass for astronomical purposes as well as a dry compass for seafaring, in his well-knownEpistola de magnete.[46]

(, Collection of the Most Important Military Techniques) 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.

(2nd printing ed.). San Francisco: Academic press. p.1.ISBN0-12-491242-7.

. Oxford University Press. pp.1446.ISBN978-0-19-981257-8.

In December 1932, the newly founded Silva Company of Sweden introduced its first baseplate or bearing compass that used a liquid-filled capsule to damp the swing of the magnetized needle.[81]The liquid-damped Silva took only four seconds for its needle to settle in comparison to thirty seconds for the original version.[81]

The earliest reference to a compass in theMuslim worldoccurs in aPersiantalebook from 1232,[17][60]where a compass is used for navigation during a trip in theRed Seaor thePersian Gulf.[4]The fish-shaped iron leaf described indicates that this early Chinese design has spread outside of China.[61]The earliestArabicreference to a compass, in the form of magnetic needle in a bowl of water, comes from a work by Baylak al-Qibjq, written in 1282 while in Cairo.[17][62]Al-Qibjq described a needle-and-bowl compass used for navigation on a voyage he took from Syria to Alexandria in 1242.[17]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 in theArab worldaccordingly.[17]Al-Qibjq also reports that sailors in the Indian Ocean used iron fish instead of needles.[25]

In 1300, an Arabic treatise written by theEgyptianastronomer andmuezzinIbn Simʿn describes a dry compass used for determining qibla. Like Peregrinus compass, however, Ibn Simʿns compass did not feature a compass card.[46]In the 14th century, theSyrianastronomer and timekeeperIbn al-Shatir(13041375) invented atimekeepingdevice incorporating both a universalsundialand a magnetic compass. He invented it for the purpose of finding the times ofprayers.[65]Arab navigatorsalso introduced the 32-pointcompass roseduring this time.[66]In 1399, an Egyptian reports two different kinds of magnetic compass. One instrument is a fish made of willow wood or pumpkin, into which a magnetic needle is inserted and sealed with tar or wax to prevent the penetration of water. The other instrument is a dry compass.[25]

This was achieved by heating of metal (especially if steel), known today asthermoremanence, and would have been capable of producing a weak state of magnetization.

(Mr. Kuans Geomantic Instructor), dating to 880.

Within the text, the authorWang Chongdescribes the spoon as a phenomenon that he has personally observed.

W. H. Creak: The History of the Liquid Compass,

Robert Southeysuggested that theSiete Partidascontained a reference from the 1250s to the needle being used for navigation.[53]

device for land navigation is recorded in aSong Dynastybook dated to 104044. There is 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. The

Three compasses meant for establishing themeridianwere described byPeter Peregrinusin 1269 (referring to experiments made before 1248)[97]Late in the 13th century,al-Malik al-Ashrafof Yemen wrote a treatise on astrolabes, which included instructions and diagrams on using the compass to determine themeridian(khaṭṭ niṣf al-nahr) andQibla.[46]In 1300, a treatise written by theEgyptianastronomer andmuezzinIbn Simʿn describes a dry compass for use as a Qibla indicator to find the direction toMecca. Ibn Simʿns compass, however, did not feature a compass card nor the familiar glass box.[46]In the 14th century, theSyrianastronomer and timekeeperIbn al-Shatir(13041375) invented atimekeepingdevice incorporating both a universalsundialand a magnetic compass. He invented it for the purpose of finding the times ofsalatprayers.[65]

A number of early cultures usedlodestones, suspended so they could turn, as magnetic compasses for navigation. Early mechanical compasses are referenced in written records of theChinese, who began using it for navigation sometime between the 9th and 11th century, some time before 1050, possibly as early as 850.[14][6]At present, according to Kreutz, scholarly consensus is that the Chinese invention used in navigation pre-dates the first European mention of a compass by 150 years.[15]The first recorded appearance of the use of the compass in Europe (1190)[16]is earlier than in the Muslim world (1232),[17][18]as a description of a magnetized needle and its use among sailors occurs inAlexander NeckamsDe naturis rerum(On the Natures of Things), written in 1190.[16][19]

The compass was used inSong DynastyChina by the military fornavigational orienteeringby 104044,

The development of the magnetic compass is highly uncertain. The compass is mentioned in fourth-century ADbooks; moreover, its early name ofmacchayantra(fish machine) suggest a chinese origin. In its Indian form, the wet compass often consisted of a fish-shaped magnet, float in a bowl filled with oil.[69][70]This fish shape is due to its name, which is composed of the wordsmacchameaningfishandyantrameaningdevice.[61]

The typical Chinese navigational compass was in the form of a magnetic needle floating in a bowl of water.[39]According toNeedham, the Chinese in theSong Dynastyand continuingYuan Dynastydid make use of a dry compass, although this type never became as widely used in China as the wet compass.[40]Evidence of this is found in theShilin guangji(Guide Through the Forest of Affairs), published in 1325 by Chen Yuanjing, although its compilation had taken place between 1100 and 1250.[40]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 lodestone sealed in by wax, and if rotated, the needle at the tail would always point in the northern cardinal direction.[40]Although the European compass-card in box frame and dry pivot needle was adopted in China after its use was taken byJapanese piratesin the 16th century (who had in turn learned of it from Europeans),[41]the Chinese design of the suspended dry compass persisted in use well into the 18th century.[42]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, and claims that there is no clear indication that Chinese mariners ever used anything but the floating needle in a bowl until the 16th century.[39]

It is well to observe the force and virtue of consequences of discoveries, and there are to be seen nowhere more conspicuously than in those three which were unknown to the ancients, and of which the origins, although recent, are obscure and inglorious; namely printing, gunpowder, and the magnet. For these three have changed the whole state of things throughout the world; the first in literature, the second in warfare, the third in navigation; whence have followed innumerable changes, insomuch that no empire, no secret, no star seems to have exerted greater power in human affairs than these mechanical discoveries… had done more to transform the modern

There is evidence that the distribution of the compass from China likely also reached eastern Africa by way of trade through the end of the Silk Road that ended inEast Africancentre of trade inSomaliaand theSwahilicity-state kingdoms.[71]There is evidence that Swahili maritime merchants and sailors acquired the compass at some point and used it for navigation.[72]

In the Mediterranean, the introduction of the compass, at first only known as a magnetized pointer floating in a bowl of water,[54]went hand in hand with improvements indead reckoningmethods, and the development ofPortolan charts, leading to more navigation during winter months in the second half of the 13th century.[55][6]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.[56]The additional few months were of considerable economic importance. For instance, it enabledVenetianconvoys to make two round trips a year to theLevant, instead of one.[57]

The Oxford Encyclopedia of Philosophy, Science, and Technology in Islam

Thus, the use of a magnetic compass by the military forland navigationoccurred sometime before 1044, but incontestable evidence for the use of the compass as a maritime navigational device did not appear until 1117.

While pivoting needles in glass boxes had already been described by the French scholarPeter Peregrinusin 1269,[73]and by the Egyptian scholar Ibn Simʿn in 1300,[46]traditionallyFlavio Gioja(fl. 1302), an ItalianpilotfromAmalfi, has been credited with perfecting the sailors compass by suspending its needle over a compass card, thus giving the compass its familiar appearance.[74][6]Such a compass with the needle attached to a rotating card is also described in a commentary onDantesDivine Comedyfrom 1380, while an earlier source refers to a portable compass in a box (1318),[75]supporting the notion that the dry compass was known in Europe by then.[39]

The first gyroscope for scientific use was made by the French physicist Jean Bernard Lon Foucault (18191868) in 1852, who also named the device, while researching in the same line that led him to use the eponymous pendulum, for which he was awarded a Copley Medal by the Royal Society. The gyrocompass was patented in 1885 by Marinus Gerardus van den Bos in The Netherlands after continuous spinning was made possible by small electric motors, which were in turn a technological outcome of the discovery of magnetic induction.[6]Yet only in 1906 was the German inventor Hermann Anschtz-Kaempfe (18721931) able to build the first practical gyrocompass. It had two major advantages over magnetic compasses: it indicated true north and was unaffected by ferromagnetic materials, such as the steel hull of ships. Thus, it was widely used in the warships of World War I and modern aircraft.

Diagram of aMing Dynastymariners compass

A sun compass uses the position of the Sun in the sky to determine the directions of the cardinal points, making allowance for the local latitude and longitude, time of day,equation of time, and so on. At fairly high latitudes, an analog-displaywatchcan be used as a very approximate sun compass. A simple sundial can be used as a much better one. An automatic sun compass developed by Lt. Col.James Allason, a mechanised cavalry officer, was adopted by the British Army in India in 1938 for use in tanks and other armoured vehicles where the magnetic field was subject to distortion, affecting the standard issue prismatic compass. Cloudy skies prohibited its use in European theatres. A copy of the manual is preserved in theImperial War Museumin London.[102]

Liquid compasses were next adapted for aircraft. In 1909, CaptainF.O. Creagh-Osborne, Superintendent of Compasses at the Admiralty, introduced hisCreagh-Osborneaircraft compass, which used a mixture of alcohol and distilled water to damp the compass card.[91][92]After the success of this invention, Capt. Creagh-Osborne adapted his design to a much smaller pocket model[93]for individual use[94]by officers of artillery or infantry, receiving a patent in 1915.[95]

However, there are questions over diffusion. Some historians suggest that the Arabs introduced the compass from China to Europe.[20][21]Some suggested the compass was transmitted from China to Europe and the Muslim world via the Indian Ocean,[22]or was brought by the crusaders to Europe from China.[23]However, some scholars proposed an independent European invention of the compass:[24][25]

Early in the Han Dynasty, between 300-200 BC, the Chinese fashioned a rudimentary compass out of lodestone… the compass may have been used in the search for gems and the selection of sites for houses… their directive power led to the use of compasses for navigation

The first incontestable reference to a

lies in the 4th century BC writings ofWang Xu(): The lodestone attracts iron.

text written by Ma Kao. The same passage is also attributed to the 4th-century AD writer Tshui Pao, although it is postulated that the former text is more authentic. The shape of the needle is compared to that of a tadpole, and may indicate the transition between lodestone spoons and iron needles.

The magnetic compass was first invented as a device fordivinationas early as the(since about 206 BC).

While the Chinese achieved magneticremanenceand induction by this time, in both Europe and Asia the phenomenon was attributed to the supernatural and occult, until about 1600 whenWilliam Gilbertpublished his

, Vol. 56, No. 3 (1920), pp. 238-239

Friedrich Hirthsuggested that Arab and Persian traders, who learned about the polarity of the magnetic needle from the Chinese, applied the compass for navigation before the Chinese did.[67]However, Needham described this theory as erroneous and it originates because of a mistraslation of the termchia-lingfound inZhu Yus bookPingchow Table Talks.[68]

Gbor Horvth; et al. (2011).On the trail of Vikings with polarized skylight.

), which records that But when the south pointing spoon is thrown upon the ground, it comes to rest pointing at the south.

Evidence for the orientation of buildings by the means of a magnetic compass can be found in 12th-centuryDenmark: one fourth of its 570Romanesque churchesare rotated by 515 degrees clockwise from true east-west, thus corresponding to the predominant magnetic declination of the time of their construction.[98]Most of these churches were built in the 12th century, indicating a fairly common usage of magnetic compasses inEuropeby then.[99]

. London: Cambridge University Press. p.281.ISBN978-0-521-67596-3.

The liquid compass is a design in which the magnetized needle or card is damped by fluid to protect against excessive swing or wobble, improving readability while reducing wear. A rudimentary working model of a liquid compass was introduced by SirEdmund Halleyat a meeting of theRoyal Societyin 1690.[85]However, as early liquid compasses were fairly cumbersome and heavy, and subject to damage, their main advantage was aboard ship. Protected in abinnacleand normallygimbal-mounted, the liquid inside the compass housing effectively damped shock and vibration, while eliminating excessive swing and grounding of the card caused by the pitch and roll of the vessel. The first liquid mariners compass believed practicable for limited use was patented by the Englishman Francis Crow in 1813.[86][87]Liquid-damped marine compasses for ships and small boats were occasionally used by theRoyal Navyfrom the 1830s through 1860, but the standard Admiralty compass remained a dry-mount type.[88]In the latter year, the American physicist and inventorEdward Samuel Ritchiepatented a greatly improved liquid marine compass that was adopted in revised form for general use by theUnited States Navy, and later purchased by the Royal Navy as well.[89]

The dry mariners compass consists of three elements: A freely pivoting needle on a pin enclosed in a little box with a glass cover and awind 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.[3]Later, compasses were often fitted into agimbalmounting to reduce grounding of the needle or card when used on the pitching and rolling deck of a ship.

and was used for maritime navigation by 1111 to 1117.

is a Chinese work composed between 70 and 80 AD (

Guarnieri, M. (2014). Once Upon a Time, the Compass.

, written by thescientistShen Kuo, contained a detailed description of howgeomancersmagnetized aneedleby rubbing its tip with lodestone, and hung the magnetic needle with one single strain ofsilkwith 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.

There is disagreement as to exactly when the compass was invented. These are noteworthyChineseliterary references in evidence for its antiquity:

that the south-pointing spoons of the Han dynasty were magnetized lodestones.

In 1928, Gunnar Tillander, a Swedish unemployed instrument maker and avid participant in the sport oforienteering, invented a new style of bearing compass. Dissatisfied with existing field compasses, which required a separate protractor in order to take bearings from a map, Tillander decided to incorporate both instruments into a single instrument. It combined a compass with a protractor built into the base. His design featured a metal compass capsule containing a magnetic needle with orienting marks mounted into a transparent protractor baseplate with a lubber line (later called adirection of travel indicator). By rotating the capsule to align the needle with the orienting marks, the course bearing could be read at the lubber line. Moreover, by aligning the baseplate with a course drawn on a map ignoring the needle the compass could also function as a protractor. Tillander took his design to fellow orienteersBjörn, Alvid, and Alvar Kjellström, who were selling basic compasses, and the four men modified Tillanders design.[81]In December 1932, the Silva Company was formed with Tillander and the three Kjellström brothers, and the company began manufacturing and selling itsSilva orienteering compassto Swedish orienteers, outdoorsmen, and army officers.[81][82][83][84]

Abearing compassis a magnetic compass mounted in such a way that it allows the taking ofbearingsof objects by aligning them with thelubber lineof the bearing compass.[76]Asurveyors compassis a specialized compass made to accurately measure heading of landmarks and measure horizontal angles to help withmap making. These were already in common use by the early 18th century and are described in the 1728Cyclopaedia. The bearing compass was steadily reduced in size and weight to increase portability, resulting in a model that could be carried and operated in one hand. In 1885, a patent was granted for ahand compassfitted with a viewing prism and lens that enabled the user to accurately sight the heading of geographical landmarks, thus creating theprismatic compass.[77]Another sighting method was by means of a reflective mirror. First patented in 1902, theBzard compassconsisted of a field compass with a mirror mounted above it.[78][79]This arrangement enabled the user to align the compass with an objective while simultaneously viewing its bearing in the mirror.[78][80]

The compass was invented in China during theHan Dynastybetween the 2nd century BC and 1st century AD, where it was called the south-governor (snn).[2]The magnetic compass was not, at first, used for navigation, but forgeomancyandfortune-tellingby theChinese. The earliestcompasses were possibly used to order and harmonize buildings in accordance with the geomantic principles offeng shui. These early compasses were made withlodestone, a form of the mineralmagnetitethat is a naturally occurringmagnetand aligns itself with the Earths magnetic field.[6]People in ancient China discovered that if a lodestone was suspended so it could turn freely, it would always point toward the magnetic poles. Early compasses were used to choose areas suitable for building houses, growing crops, and to search for rare gems. Compasses were later adapted for navigation during theSong Dynastyin the 11th century.[1]

The use of a compass as a direction finder underground was pioneered in theTuscanmining townMassawhere floating magnetic needles were employed for tunnelling, and for defining the claims of the various mining companies, as early as the 13th century.[100]In the second half of the 15th century, the compass became standard equipment forTyrolianminers. Shortly afterwards the first detailed treatise dealing with the underground use of compasses was published by aGermanminerRlein von Calw(14631525).[101]

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