Fathom
From Wikipedia, the free encyclopedia
| SI units | |
|---|---|
| 1.82880 m | 182.880 cm |
| US customary / Imperial units | |
| 6.00000 ft | 72.0000 in |
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 'a pair of outstretched arms'.[1][2] In Middle English it was fathme. Its size varied slightly depending on its base definition, either based on a thousandth of an (Admiralty) nautical mile or as a multiple of the imperial yard. There are 2 yards (6 feet) in a fathom.[3]
Contents |
[edit] 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 fathoms)
- 4 cubits (1 cubit is exactly 0.25 fathoms)
- 6 feet (1 foot is about 0.1667 fathoms)
- 18 hands
- 72 inches
In 1954 the United States and countries of the Commonwealth of Nations defined the length of the international yard to be exactly 0.9144 metres. With the adoption of the metric SI system the use of fathoms declined.
[edit] 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 fathom was always regarded as exactly 6 feet. 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.
[edit] Use of the fathom
The fathom is now of mainly historical interest. In most countries, it is an obsolete unit and has not been used in maritime affairs for decades. All nautical charts produced by Hydrographic Offices worldwide (except for those produced by the U.S. Hydrographic Office, which uses feet and fathoms.[4] ) indicate depths in metres. Until early in the twentieth century, it was the unit used to measure the depth of mines (mineral extraction) in the United Kingdom.[5]
[edit] 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.[6]
[edit] 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 |
| 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) |
| India (State of Manipur) | Sana lamjel | n/a |
| Italian | braccio | n/a |
| Japanese | hiro (尋) | ~1.818 |
| Maltese | qasba | ~2.096 |
| Norwegian | favn | 1.882[7] |
| Polish | sążeń | 1.728 |
| Portuguese | braça | n/a |
| Russian | morskaya sazhen (морская сажень) | 1.852 |
| Turkish | kulaç | 1.83 |
| Sanskrit | vyama | n/a |
| Serbian | hvat (хват) | n/a |
| Slovak | siaha | n/a |
| Spanish | braza | 1.6718 |
| Swedish | famn | 1.7814 |
[edit] See also
- English unit
- Imperial unit
- United States customary units
- International System of Units
- Ancient Greek units of measurement
- Sounding line
[edit] Notes
- ^ Oxford English Dictionary, second edition, 1989;
- ^ Bosworth, Joseph; Thomas Toller (ed.) (1898). An Anglo-Saxon Dictionary. Oxford, England: Clarendon Press.
- ^ Encyclopædia Britannica eleventh edition 1911.
- ^ NOAA Chart. Retrieved on 2008-05-22.
- ^ Mining Encyclopaedia. Retrieved on 2007-05-28.
- ^ Hirsch, Jr, E.D.; Kett, Joseph F; Trefi, James (2002). The New Dictionary of Cultural Literacy. Boston, MA: Houghton Mifflin. ISBN 0618226478.
- ^ Bokmålsordboka. Retrieved on 2008-01-29.
[edit] References
- Fenna, Donald (2002). A Dictionary of Weights, Measures, and Units. Oxford University Press. ISBN 0198605226.
