From Wikipedia, the free encyclopedia

This derivation of the Vitruvian Man by Leonardo da Vinci, depicts nine historical units of measurement: the yard, the span, the cubit, the Flemish ell, the English ell, the French ell, the fathom, the hand, and the foot. The Vitruvian Man was drawn to scale, so the units depicted are displayed with their proper historical ratios.

A fathom is a unit of length in the Imperial system (and the derived U.S. customary units), used especially for measuring the depth of water.

There are 2 yards (6 feet) in a fathom.^[1] Based on the distance between the fingertips of a man's outstretched arms, its size varied slightly depending on whether it was defined as a thousandth of an (Admiralty) nautical mile or as a multiple of the imperial yard. Formerly, the term was used for any of several units of length varying around 5 and 5½ feet.

The name derives from the Old English word fæðm meaning embracing arms or a pair of outstretched arms.^[2][3][4] In Middle English it was fathme.

A brass was a unit of length equal to a fathom. A cable length, based on the length of a ship's cable, has been variously reckoned as equal to 100 or 120 fathoms. At one time, a quarter meant a fourth of a fathom.

Abbreviations: f, fath, fm, fth, fthm.

International fathom

One fathom is equal to:

• 1.8288 metres (1 metre is about 0.5468 fathoms)
• 2 yards (1 yard is exactly 0.5 fathom)
• 6 feet (1 foot is about 0.1667 fathoms)
• 18 hands
• 72 inches

In 1959 the United States, Australia, Canada, New Zealand, South Africa, and the United Kingdom defined the length of the international yard to be exactly 0.9144 metre. With the adoption of the metric SI system the use of fathoms declined.

British fathom

The British Admiralty defined a fathom to be a thousandth of an imperial nautical mile (which was 6080 ft) or 6.08 feet. In practice the "warship fathom" of exactly 6 feet was used in Britain and the United States.^[5] No conflict in the real world existed as depths on Imperial nautical charts were indicated in feet if less than 30 feet and in fathoms for depths above that. Until the 19th century in England, the length of the fathom was more variable: from 5½ feet on merchant vessels to either 5 feet or 7 feet on fishing vessels.^[5]

Use of the fathom

Water depth

Most modern nautical charts indicate depth in metres. However, the U.S. Hydrographic Office uses feet and fathoms.^[6] A nautical chart will always explicitly indicate the units of depth used.

To measure the depth of shallow waters, boatmen used a sounding line containing fathom points, some marked and others in between, called deeps, unmarked but estimated by the user.^[7] Water near the coast and not too deep to be fathomed by a hand sounding line was referred to as in soundings or on soundings.^[8] The area offshore beyond the 100 fathom line, too deep to be fathomed by a hand sounding line, was referred to as offsoundings or out of soundings.^[9] A deep-sea lead, the heaviest of sounding leads, was used in water exceeding 100 fathoms in depth.^[10]

This technique has been superseded by sonic depth finders for measuring mechanically the depth of water beneath a ship, one version of which is the Fathometer (trademark).^[11] The record made by such a device is a fathogram.^[12] A fathom line or fathom curve, a usually sinuous line on a nautical chart, joins all points having the same depth of water, thereby indicating the contour of the ocean floor.^[13]

Line length

The components of a commercial fisherman’s setline were measured in fathoms. The rope called groundline, used to form the main line of a setline, was usually provided in bundles of 300 fathoms. A single 50-fathom skein of this rope was referred to as a line. Especially in Pacific coast fisheries the setline was composed of units called skates, each consisting of several hundred fathoms of groundline, with gangions and hooks attached. A tuck seine or tuck net about 70 fathoms long and very deep in the middle was used to take fish from a larger seine.

A line attached to a whaling harpoon was about 150 fathoms long. A forerunner — a piece of cloth tied on a ship's log line some fathoms from the outboard end — marked the limit of drift line. A kite was a drag, towed under water at any depth up to about 40 fathoms, that on striking bottom was upset and rose to the surface.

A shot, one of the forged lengths of chain joined by shackles to form an anchor cable, was usually 15 fathoms long.

In Finland, fathom (syli) is sometimes, albeit seldom, used as a maritime unit, 1/1000th of a nautical mile and 1/100th of cable length.

Burial

It is customary, when burying the dead, to inter the corpse at a fathom's depth, or six feet under. A burial at sea (where the body is weighted to force it to the bottom) requires a minimum of six fathoms of water. This is the origin of the phrase to deep six, meaning to discard, or dispose of.^[14]

On land

Until early in the 20th century, it was the unit used to measure the depth of mines (mineral extraction) in the United Kingdom.^[15] Miners also use it as a unit of area equal to 6 square feet in the plane of a vein.^[2] In Britain, it can mean the quantity of wood in a pile of any length measuring 6 feet square in cross section.^[2]

Other fathoms and similar units of length

Units of length similar to the size of the fathom can be found in many cultures. Some are listed below.

See also

• Anthropic units
• Bathymetry
• English unit
• Imperial unit
• United States customary units
• International System of Units
• Ancient Greek units of measurement
• Sounding line

Notes

References

• Fenna, Donald (2002), "fathom", A Dictionary of Weights, Measures, and Units, Oxford: University Press, ISBN 0198605226 .

External links

• An explanation of the fathom marks used at sea (retrieved Sept 2005).
• Fathom - LoveToKnow 1911. 1911 Encyclopedia Britannica - Free Online.
• Hungarian web page that refers to the length of a "bécsi öl"

From LoveToKnow 1911

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From BibleWiki

(Old A.S. faethm, "bosom," or the outstretched arms), a span of six feet (Acts 27:28). Gr. orguia (from orego, "I stretch"), the distance between the extremities of both arms fully stretched out.

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From Wikia Gaming, your source for walkthroughs, games, guides, and more!

Fathom
Developer(s)	Imagic
Publisher(s)	Imagic
Designer(s)	Rob Fulop
Release date	Atari 2600: 1983 (NA) Intellivision: 1983 (NA) ColecoVision: 1983 (NA)
Genre	Adventure
Mode(s)	Single player
Age rating(s)	N/A Atari 2600 Intellivision ColecoVision
Platform(s)	Atari 2600 Intellivision ColecoVision
Input	Atari 2600 Joystick Intellivision Controller ColecoVision Controller
Credits | Soundtrack | Codes | Walkthrough

Fathom is a game released for the Atari 2600, the ColecoVision, and the Intellivision.

Gameplay

Neptina, Neptune's daughter, has been imprisoned at the bottom of the sea by Titans. Your goal is to rescue her by locating the scattered pieces of a magical trident! You will need to take the form of a dolphin and a bird in order to locate the pieces that are hidden in the ocean and clouds. When flying in the air, there are several screens that have clouds flying by. Touch all of the clouds, and the trident piece appears! Other birds which are flying around will cause you to lose energy if you touch them accidentally. Underwater, trident pieces can be found by touching the sea horses. Octopuses, sharks, and a deadly maze of seaweed will get in your way and cause you to lose energy if caught! When you have located all of the trident pieces, the cage holding Neptina can be unlocked, but if you run out of energy first the game will be over.

Gallery

Atari 2600 Boxart

Intellivision Boxart

ColecoVision Boxart

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