Page 27 of 36

Posted: Sat Jan 26, 2008 7:08 pm
by john
kbs2244 wrote:Ish
I found his arguments believable.
I am, however, pre-disposed to believe in his premise of early, long range, open ocean, travel.
He thinks he has found the tool that made it, along with monumental constructions, possible.
He thinks the “Celtic Cross” was a real Swiss Army Knife in the right hands.
Like so many books of this “fringe” type you have to keep a real open mind.
But, he seems to have an answer to every objection.

I also feel the concept of reed boats has been woefully neglected.
(Most likely because a pile of rotten grass, if it survived very long, would not make a very exciting thesis subject.)
All -

Don't forget the compass.

The needle of iron is hematite's little brother.

Compass
From Wikipedia, the free encyclopedia

This article is about the navigational instrument. For the tool used to draw circles, see Compass (drafting). For other uses, see Compass (disambiguation).
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 magnetic compass. Fundamentally, the classic compass is any magnetically sensitive device able to indicate the direction of the magnetic north of a planet's magnetosphere. Often compasses are built as a stand-alone sealed instrument with a magnetized bar or needle turning freely upon a pivot, or floating in a fluid, thus able to point in a northerly and southerly direction.
Many enhancements have been developed. 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. An Orienteering compass consists of a ruggedized needle compass permanently attached to a transparent baseplate containing tools to assist the user in working with maps in a field setting (as opposed to in an office at a desk).
A recent development is the electronic compass, which detects the magnetic directions without requiring moving parts. This device frequently appears as an optional subsystem built into Global Positioning Satellite Receivers (GPSRs).
There are other, more accurate, devices for determining north (known in such cases as true north, as opposed to magnetic north), which do not depend on the earth's magnetic field for operation. A gyrocompass (ships) or astrocompass (aircraft) can be used to find true north, while being unaffected by stray magnetic fields, nearby electrical power circuits or nearby large masses of ferrous metals.
Contents [hide]
1 History of the navigational compass
1.1 Pre-history
1.2 Mesoamerica
1.3 Needle-and-bowl device
1.4 China
1.4.1 Later developments in China
1.4.2 Question of diffusion
1.4.3 Question of independent European invention
2 Impact in the Mediterranean
2.1 Mining
2.2 Dry compass
2.3 Liquid compass
3 Construction of a simple compass
4 Modern compasses
5 Solid state compasses
6 Bearing compass
7 Compass correction
8 Using a compass
9 Compass balancing
10 Points of the compass
11 See also
12 Gallery
13 Notes
14 References
15 External links
[edit]History of the navigational compass

[edit]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.
[edit]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]
[edit]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.
[edit]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.
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]
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]
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]
[edit]Later developments in China


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.
[edit]Question of diffusion


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:
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.
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].
[edit]Question of independent European invention


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:
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]
[edit]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]
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]
Although critics like Kreutz feels that it was later in 1410 that anyone really started steering by compass. [30]
[edit]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]
[edit]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]
[edit]Liquid compass
In 1936 Tuomas Vohlonen invented the first successful portable liquid-filled compass designed for individual use.[37]
[edit]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.
[edit]Modern compasses



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.
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.
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.
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.
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.
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 is a form of fluorescence, 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).
[edit]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.
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.
[edit]Bearing compass



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.[39]
[edit]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
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, engines, steel pitons, wristwatches, etc.)
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.
Fluxgate compasses can be calibrated automatically, and can also be programmed with the correct local compass variation so as to indicate the true heading.
[edit]Using a compass



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).
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.
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.
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.
This method is sometimes known as the Silva 1-2-3 System, after Silva Compass, manufacturers of the first protractor compasses.
A dynamic rotating draggable Silva compass is available online to practice setting compass and map bearings: http://geographyfieldwork.com/UsingCompass.htm
Literature [1]
[edit]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.
Some different compass systems:

Compass with 400 grads division and conversion table

Swiss army compass with mils division

Compass with prism (inverted graduation)

Compass with prism (bearing 220° through eyepiece)

Wrist compass of the Soviet Army with double graduation: 60° (like a watch) and 360° (below the figures for 15°, 30° and 45° of the outer graduation are the Cyrillic letters "З" (zapad = west), "Ю"(yug = south) and "В" (vostok = east)

Land surveyor compass with clinometer

Stratum compass after Prof. Clar

German Bézard compass (Company Lufft) formerly utilized in many European armies (bearing is taken through slots in lid)
[edit]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.
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.
[edit]See



And, naaaahh,

This couldn't have anything to do with respect to celestial orientation, or, gasp, the sunwheel.

Let alone boats, hematite, or televison ( I'm not done yet, there,Ishtar).

Let alone precession.

As a very general point, I'd say the evidence for very early and sophisticated cognition continues to stack..........


john

Posted: Sun Jan 27, 2008 1:10 am
by Ishtar
Forum Monk wrote:
Just what I thought. Its not greek, much less from the 6th century BC
It's not Greek, much less from the 6th century BC because ...

btw - sincerely, you did a great job finding the picture. You must be a google master.
:wink:
Yeah, it was really difficult and time consuming. Click Google images. Put in astrology+Greek. Not on first page. Found it on second.

I think you're dragging your metaphorical feet, FM! :wink:

Posted: Sun Jan 27, 2008 1:23 am
by Ishtar
kbs2244 wrote:Ish
I found his arguments believable.
I am, however, pre-disposed to believe in his premise of early, long range, open ocean, travel.
Thanks KB. I'm looking forward to reading it. I'm always really careful with 'fringe' books. I read Acharya's through a sieve and was glad that I did, once I got to her theory of Krishna's mother being a virgin.

For the record, I think she's a terrible researcher, especially in the Indian stuff where she hasn't got a clue and is relying on 19th century, staunchly Christian Raj-inspired writers who still think that Krishna is a product of European or even Russian writers (but never Indian!). She didn't go back to the scriptures themselves until I insisted that she did. Then she did a hotch potch job by mixing up the goddess Aditi in the Rig-veda with Aditi, the wife of Kashyapa Muni in the Srimad Bhagavatham to make her point. Then she sent out an email to all her followers instructing them to that this was the new line. It will be torn apart by even the most average Vedic scholar in seconds.

Anyway, none of this takes away from the theory of astrotheism which, as you rightly pointed out, they were burning people at the stake for long before Acharya came along.

In the book, does Miller say where got the Greek astrology map? FM's decided that it must be a fake.

Posted: Sun Jan 27, 2008 1:37 am
by Ishtar
Did Hipparchus discover precession in the 2nd century CE, or did man know about it before that? That's the question we've been trying to answer, in order to eee if the some of the Bible stories are allegories marking the turn of the ages, an astronomical phenomena which is caused by precession.

Here's the view of Wiki, which is after all, not the final word, but a consensus of what most experts think and so is useful to us from that point of view so we don't try to reinvent the wheel:

Though there is still-controversial evidence that Aristarchus of Samos possessed distinct values for the sidereal and tropical years as early as ca. 280 BC, the discovery of precession is usually attributed to Hipparchus of Rhodes or Nicaea, a Greek astronomer who was active in the 2nd century BC. Virtually all Hipparchus' writings are lost, including his work on precession. They are mentioned in Ptolemy's Almagest, where precession is explained as the rotation of the celestial sphere around a motionless Earth. It is reasonable to assume that Hipparchus, like Ptolemy, thought of precession in geocentric terms as a motion of the heavens. The first definite reference to precession as the result of a motion of the Earth's axis is Nicolaus Copernicus's De revolutionibus orbium coelestium (1543). He called precession the third motion of the earth. Over a century later it was explained in Isaac Newton's Philosophiae Naturalis Principia Mathematica (1687) to be a consequence of gravitation (Evans 1998, p. 246). However, Newton's original precession equations did not work and were revised considerably by Jean le Rond d'Alembert and subsequent scientists.

Various claims have been made that other cultures discovered precession independent of Hipparchus. At one point it was suggested that the Babylonians may have known about precession. According to al-Battani, Chaldean astronomers had distinguished the tropical and sidereal year (the value of precession is equivalent to the difference between the tropical and sidereal years). He stated that they had, around 330 BC, an estimation for the length of the sidereal year to be SK = 365 days 6 hours 11 min (= 365.258 days) with an error of (about) 2 min. It was claimed by P. Schnabel in 1923 that Kidinnu theorized about precession in 315 BC (Neugebauer, O. "The Alleged Babylonian Discovery of the Precession of the Equinoxes," Journal of the American Oriental Society, Vol. 70, No. 1. (Jan. - Mar., 1950), pp. 1-8.) Neugebauer's work on this issue in the 1950s superseded Schnabel's (and earlier, Kugler's) theory of a Babylonian discoverer of precession.

Similar claims have been made that precession was known in Ancient Egypt prior to the time of Hipparchus. Some buildings in the Karnak temple complex, for instance, were allegedly oriented towards the point on the horizon where certain stars rose or set at key times of the year. A few centuries later, when precession made the orientations obsolete, the temples would be rebuilt. Note however that the observation that a stellar alignment has grown wrong does not necessarily mean that the Egyptians understood that the stars moved across the sky at the rate of about one degree per 72 years. Nonetheless, they kept accurate calendars and if they recorded the date of the temple reconstructions it would be a fairly simple matter to plot the rough precession rate. The Dendera Zodiac, a star-map from the Hathor temple at Dendera from a late (Ptolemaic) age, supposedly records precession of the equinoxes (Tompkins 1971). In any case, if the ancient Egyptians knew of precession, their knowledge is not recorded in surviving astronomical texts.

The former professor of the history of science at MIT, Giorgio de Santillana, argues in his book, Hamlet's Mill, that many ancient cultures may have known of the slow movement of the stars across the sky; the observable result of the precession of the equinox. This 700 page book, co-authored by Hertha von Dechend, makes reference to approximately 200 myths from over 30 ancient cultures that hinted at the motion of the heavens, some of which are thought to date to the neolithic period.
As I said before, I don't think we're going to prove it here, either way. I was interested to see, however, that Giorgio de Santillana of Hamlet's Mill was a history of science professor at MIT.

Posted: Sun Jan 27, 2008 12:46 pm
by kbs2244
Miller doesn’t talk much about the Zodiac. Only 6 pages in a 168 page chapter about “Gods in the Sky.” That is where he gets into Precession, the Ecliptic, The Figure Eight, etc.
He is more into the practical side. Navigation, calendars, construction.
The following chapter is called “Gods Brought to Earth.” It is on how the knowledge of the stars was put to practical use.
(The first 2 chapters are about him personally, how he feels about finding this “Gift” from the past, his views of the current social situation, etc. Other than the historical prospective of how knowledge, power, and religion are tied together, these chapters are the only meta-physical ones.)

Posted: Sun Jan 27, 2008 12:53 pm
by Ishtar
Oh dear. Doesn't sound like he had an editor. No wonder you took weeks to read and digest it. Two chapters about him personally sounds like pure indulgence.

Posted: Sun Jan 27, 2008 12:56 pm
by Minimalist
Virtually all Hipparchus' writings are lost, including his work on precession.
See, the problem with this is that we don't even know if Hipparchus claimed to have discovered precession or if he indicated that he got the idea from someone else. Chalk up another loss for mankind in the burnings of the library at Alexandria.

Posted: Sun Jan 27, 2008 1:21 pm
by Ishtar
Minimalist wrote:
Virtually all Hipparchus' writings are lost, including his work on precession.
See, the problem with this is that we don't even know if Hipparchus claimed to have discovered precession or if he indicated that he got the idea from someone else. Chalk up another loss for mankind in the burnings of the library at Alexandria.
I think Hipparchus discovered a mathematical formula for something that everyone had known for ages merely by observation.

Posted: Sun Jan 27, 2008 7:53 pm
by Forum Monk
Ishtar wrote:Yeah, it was really difficult and time consuming. Click Google images. Put in astrology+Greek. Not on first page. Found it on second.

I think you're dragging your metaphorical feet, FM! :wink:
Nope. I'm not dragging my feet. I made the error of typing in "greek starmap". I did find this image:
http://www.johnpratt.com/items/docs/lds ... _map_n.jpg

But though it purports to show greek constellations, it is labeled in english using a roman font. Obviously not greek in origin.
I think Hipparchus discovered a mathematical formula for something that everyone had known for ages merely by observation.
I think he described its observable and measured it. I don't think he understood how or why it happened. In fact he thought is only affected the observation of the zodiac. It's important to note that during his career he systematically compiled and cataloged Babylonian observations. Then when he compared them to his own, the positional discrepancy was observed. After many hundreds of years of combined observation.

Posted: Sun Jan 27, 2008 7:59 pm
by kbs2244
Ish.
You are right. In the acknowledgements Miller doesn’t mention anyone by name as an editor. So, self editing is a good guess.
In the end, it isn’t all that bad. He is just kind of giving you a personal background, explaining how he got to where he is. And how he came across this “discovery.”
Those first 2 chapters are only 15 percent of the whole book, and there is a lot of interesting facts mixed into his personal story.
All in all, I expect you will enjoy the book. It is well crafted.

BTW, In a quick re-reading, he seems to agree with your opinion of Hipparchus coming up with something that explained, and allowed prediction of, a long observed phenomena.
Again, he seems more interested in the history of the useful application of knowledge, then in history of the knowledge itself.

Posted: Sun Jan 27, 2008 8:10 pm
by kbs2244
On a somewhat related note,
Rattling around the back of my head is the faint recollection of one of those “human interest” stories that show up in the papers.
This related how, when the US troops stormed into Baghdad one of the groups of troops came across a “school” (for lack of a better term) where they took nightly observations of the star positions.
When asked why, they explained that “we have always done it.”
They had records going back thousands of years.
The reporter called it “The longest ongoing scientific experiment on Earth.”
Does anyone else remember this?
I have no references and would like to find some.

Posted: Mon Jan 28, 2008 12:13 am
by Ishtar
kbs2244 wrote:On a somewhat related note,
Rattling around the back of my head is the faint recollection of one of those “human interest” stories that show up in the papers.
This related how, when the US troops stormed into Baghdad one of the groups of troops came across a “school” (for lack of a better term) where they took nightly observations of the star positions.
When asked why, they explained that “we have always done it.”
They had records going back thousands of years.
The reporter called it “The longest ongoing scientific experiment on Earth.”
Does anyone else remember this?
I have no references and would like to find some.
Goodness, KB. Sounds like the original Babylonian star observatory is still there...well, that is, is if it hasn't been now been bombed - or destroyed like the Library at Alexandria. It would be good to know more about this.

Posted: Mon Jan 28, 2008 12:20 am
by Ishtar
Forum Monk wrote: Nope. I'm not dragging my feet. I made the error of typing in "greek starmap". I did find this image:
http://www.johnpratt.com/items/docs/lds ... _map_n.jpg

But though it purports to show greek constellations, it is labeled in english using a roman font. Obviously not greek in origin.
I can't see how the map you found relates to Miller's map. Why do you think the map of Miller is not Greek or 6th century BC? Are you saying Miller based his map on this one? Do you think Miller added on his own cross of the equinoxes afterwards?

I think he described its observable and measured it. I don't think he understood how or why it happened. In fact he thought is only affected the observation of the zodiac. It's important to note that during his career he systematically compiled and cataloged Babylonian observations. Then when he compared them to his own, the positional discrepancy was observed. After many hundreds of years of combined observation.
As it says in the Wiki quote posted a few back, all his writings on precession are lost. So I'm wondering what your views above are based on?

Posted: Mon Jan 28, 2008 2:32 am
by Ishtar
Why is the Club having problems in attesting precession? I blame the Age of Enlightenment and its insistence on intellectual reason being the primary authority.

I’m not saying that we shouldn’t use intellectual reason. Of course not. That would be crazy. But we’ve gone from making it our primary authority to making it our only authority, forgetting that knowledge used to be transmitted in another form, notably metaphor and allegory in the form of poetry, where the sound of the word and the feeling it conveyed was as equally important as its meaning.

Poetry – unlike post Enlightenment thinking – is beyond reason. But it’s not unreasonable. It just reaches further into a more holistic construct that satisfies the heart as well as the head.

The ancients used to orally record and transmit their knowledge in verse, through a priestly class that kept it secret. They hid their truths so that only those trained to have the vision would see the underlying deeper meaning in these beautiful stories created over the top of them.

As Thomas Hardy once said:

“If Galileo had said in verse that the world moved, the Inquisition might have left him alone.”

In earlier days, the poets' words themselves (and not just their meanings) were believed to contain power. That’s why the witches’ books of magic – the Grimoires - contained what are known as ‘spells’.

WB Yeats says that the poets or bards of ancient Ireland were so feared because of this:

“The bards were the most powerful influence in the land, and all manner of superstitious reverence environed them round. No gift they demanded might be refused them. ... A poem and an incantation were almost the same. A satire could fill a whole countryside with famine. Something of the same feeling still survives, perhaps, in the extreme dread of being ‘rhymed up’ by some local maker of unkindly verses....”

But it wasn’t just the Druids and their bards.

When Zoroaster wanted to introduce his new religion in Babylonia, he had to do a deal with the most powerful power brokers in the land. Who were they? They weren’t the politicians. They weren’t the monarchy or aristocracy. They were the Kavis, the ancient lineage of Vedic poets who carried all the lore – from maths and astronomy to astrology and botany – in their orally transmitted verses of metaphor and allegory.

And so that’s why we have hundreds - according to Hamlet’s Mill - of wonderful ancient stories from all over the world that take us into a beautiful realm of rhyme and meter to describe how the stars slowly travelled across the sky, from one age to another. And instead of giving us a cold mathematical formula, they talk of great heroes, like Ilmarinen who has to fix a peg into the roof of the universe to stop it spinning off its axis; or of Atlas who, in classical art, is not supporting on his shoulders the world, but the whole celestial sphere:

Image

And in most of these metaphorical poems, the changing of the age is represented by an apocalyptic end of the world.

Nowadays, we only have fragments of these great poems and because we are trained in post-Enlightenment thinking and reasoning, we hungrily scour them with our well-honed intellects for historical facts or scientific models or mathematical formulae. We live in age where poetry is considered to be a superficial frippery, relegated to the dustbin of St Valentine’s Day. In any case, we’re not trained in how to appreciate it, especially as the sound aspect of the words is lost in translation.

So we may read these myths and think that they’re just a nice but obscure distraction, or even complete nonsense, all the while searching for other ‘evidence’ to show a scientific attestation that these ancient writers knew about precession - when all the time, the truth is right under our noses.

But because we can't see it, we call the ancients 'ignorant barbarians'.

I wonder what they'd have thought of us.

Posted: Mon Jan 28, 2008 6:43 am
by Forum Monk
Ishtar wrote:I can't see how the map you found relates to Miller's map. Why do you think the map of Miller is not Greek or 6th century BC? Are you saying Miller based his map on this one? Do you think Miller added on his own cross of the equinoxes afterwards?
You can't see the relationship because there is none. Nor did I say there was a relationship. All I said was I found that image. Ironically it also claimed to be greek and like Miller's it was written in english with a roman font and to make it even more obvious, Miller's used roman numerals. Nothing about either appears genuine, in my opinion.
Ishtar wrote: As it says in the Wiki quote posted a few back, all his writings on precession are lost. So I'm wondering what your views above are based on?
If none of his books survived, how do we know he discovered it? Because others, most notably, Ptolemy's writings did survive, in particular the Almagest, in which he describes at length the contribution of Hipparchus who preceeded Ptolemy by 300 years.

We know from Ptolemy, that Hipparchus had several theories to try to explain the observable and considered the possibility that the entire dome of stars was moving, though his historical observations were not conclusive. The Wiki article mentions the fact he thought precession only affected the zodiac or just the bright stars of the zodiac which were some of the ideas Hipp. considered.

Hipp. did derive a value of 46" per year and used it to generate some new star maps which he compared to his own obersvations. Hipp. was a genius who contributed many ground-breaking ideas to astronomy and calculated a better value of precession than Ptolemy who was working 300 years later. It wasn't until the second century that a general value of one degree per 100 years was realized.