Fathom
A fathom is a unit of length in the Imperial system (and the derived U.S. customary units). The name derives from the Old English word fæðm meaning 'outstretched arms'.[1][2][3] In Middle English it was fathme. Its size can vary from system to system. The most commonly used fathom today is the international fathom. There are 2 yards (6 feet) in a fathom.[4]
International fathom
In 1958 the United States and countries of the Commonwealth of Nations defined the length of the international yard to be 0.9144 metres. Consequently, the international fathom is defined to be equal to 1.8288 metres.
1 international fathom is equal to:
- 6 feet (1 foot is about 0.1667 fathoms)
- 2 yards (1 yard is exactly 0.5 fathoms)
- 1.8288 metres (1 metre is about 0.5468 fathoms)
- 72 inches
British Fathom
Prior to that standardization on the international fathom, the British Admiralty defined a fathom to be a thousandth of an imperial nautical mile (which was 6080 ft) or 6.08 feet. This is equivalent to 1.853184 metres.
Use of the fathom
Once also used for measuring distances on land, the fathom is now restricted to nautical uses, especially expressing the depth of water or the length of nautical rope or cable. Until early in the twentieth century, it was the unit used to measure the depth of mines in the United Kingdom.[5]
Civilian maps in English-speaking countries used to have depths commonly marked in fathoms, but this has changed to metres generally, even in US maps. Nautical charts have changed on a separate schedule.
Burial
It is customary, when burying the dead in the USA and elsewhere, 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.[6]
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.
| Culture | Name | Length in metres |
|---|---|---|
| Croatian | hvat | 1.896484 |
| Czech | sáh | 1.7928 |
| Danish | favn | 1.883124 |
| Dutch | vadem, vaam | 1.883679 |
| Esperanto | klafto | n/a |
| Estonian | süld | n/a |
| Finnish | syli | n/a |
| French | toise (circa 1150), brasse (1409) | ~1.949 |
| German | Klafter, Faden = 6 Fuß | n/a resp. 1.7 |
| Ancient Greek | orguia | 1.8542 |
| Hungarian | öl | 1.8964838 (Viennese) |
| Interlingua | fathom | n/a |
| India (State of Manipur) | Sana lamjel | n/a |
| Italian | braccio | n/a |
| Japanese | hiro(尋) | ~1.818 |
| Maltese | qasba | ~2.096 |
| Norwegian | famn | 2 |
| Polish | sążeń | 1.728 |
| Portuguese | braça | n/a |
| Russian | morskaya sazhen (морская сажень) | 1.852 |
| Sanskrit | vyama | n/a |
| Serbian | hvat (хват) | n/a |
| Slovak | siaha | n/a |
| Spanish | braza | 1.6718 |
| Swedish | famn | 1.7814 |
See also
- English unit
- Imperial unit
- United States customary units
- International System of Units
- Ancient Greek units of measurement
Notes
- ^ Oxford English Dictionary, second edition, 1989;
- ^ Bosworth / Toller: An Anglis-Saxon Dictionary, 1921.
- ^ http://beowulf.engl.uky.edu/cgi-bin/Bosworth-Toller/ebind2html3.cgi/bosworth?seq=285
- ^ Encyclopædia Britannica eleventh edition 1911.
- ^ "Mining Encyclopaedia". Retrieved 2007-05-28.
{{cite web}}: Cite has empty unknown parameter:|coauthors=(help) - ^ Hirsch, Jr, E.D. (2002). The New Dictionary of Cultural Literacy. Boston, MA: Houghton Mifflin. ISBN 0618226478.
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References
- Fenna, Donald (2002). A Dictionary of Weights, Measures, and Units. Oxford University Press. ISBN 0198605226.
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