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pontoon
pontoon one of a number of floats used chiefly to support a bridge, to raise a sunken ship, or to float a hydroplane or a floating dock. Pontoons have been built of wood, of hides stretched over wicker frames, of copper or tin sheet metal sheathed over wooden frames, of aluminum, and of steel. The original and widespread use was to support temporary military bridges. Cyrus the Great built (536 BC) the earliest pontoon bridge in history, using skin-covered pontoons. However, Homer mentions pontoon bridges as early as c.800 BC The U.S. army began experimenting with rubber pontoons in 1846 and in 1941 adopted collapsible floats of rubber fabric with steel-tread roadways. At the same time the navy developed box pontoons of light, welded steel for ship-to-shore bridges during landing operations. These box pontoons could be assembled into bridges, docks, causeways and, by adding a motor, into self-propelling barges. Permanent civilian pontoon bridges have been built where the water is deep and the water level fairly constant or controllable, often also where the crossing is narrow or where the bottom makes it difficult to sink piers. The modern permanent pontoon is composed of many compartments, so that if a leak occurs in one compartment, the pontoon will not sink. Permanent pontoons are fastened together and several anchors are dropped from each. Often a section of a bridge built on them can swing aside to let a ship pass. Several pontoon bridges have been built across the Mississippi River. Pontoons for raising sunken ships are watertight cylinders that are filled with water, sunk, and fastened to the submerged ship; when emptied by compressed air, they float the ship to the surface. A pontoon lifeboat consists of a raft supported by watertight cylinders. |
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Cite this article
"pontoon." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "pontoon." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-pontoon.html "pontoon." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-pontoon.html |
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pontoon
pon·toon1
/ ˌpänˈtoōn/
•
n.
a flat-bottomed boat or hollow metal cylinder used with others to support a temporary bridge or floating landing stage.
∎
a bridge or landing stage supported by pontoons.
∎
a large flat-bottomed barge or lighter equipped with cranes.
∎
either of the floats fitted to an aircraft to enable it to land on water.
pontoons pon·toon2 • n. Brit. the card game blackjack or vingt-et-un. ∎ a hand of two cards totaling 21 in this game. |
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"pontoon." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "pontoon." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-pontoon.html "pontoon." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-pontoon.html |
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pontoon
pontoon.
1. A flat-bottomed boat often used as a lighter or ferry. 2. A boat of special design to support a temporary road or footbridge across a river. 3. A hollow, watertight structure used in salvage for its lifting power when the water it contains is pumped out. See also caisson. 4. A floating structure frequently used at the ends of fixed piers or alongside quays so that it rises and falls with the tide to provide ease of access. 5. A low, flat vessel fitted with cranes, tackles, and capstans which was used in the days of sail to haul down, or careen, ships for bottom cleaning or repair. |
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"pontoon." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "pontoon." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O225-pontoon.html "pontoon." The Oxford Companion to Ships and the Sea. 2006. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O225-pontoon.html |
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pontoon
pontoon1 boat (or other vessel), of which a number are used to support a temporary bridge. XVII (ponton). — (O)F. ponton :— L. pontō, -ōn- punt, bridge of boats, f. pōns, pont- bridge, rel. to Indo-Iran. and Balto-Slav. words, with Gr. pátos, meaning ‘road’, ‘path’, but the relevance of the sense in PONTIFF (if this is ‘path-maker’) is not clear; see -OON.
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T. F. HOAD. "pontoon." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "pontoon." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-pontoon.html T. F. HOAD. "pontoon." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-pontoon.html |
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pontoon
pontoon n.
1. a flat-bottomed boat or hollow metal cylinder used with others to support a temporary bridge or floating landing stage. 2. a bridge or landing stage supported by pontoons. 3. a large flat-bottomed barge or lighter equipped with cranes and tackle for careening ships and salvage work. 4. either of two floats fitted to an aircraft to enable it to land on water. |
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"pontoon." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "pontoon." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O63-pontoon.html "pontoon." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-pontoon.html |
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pontoon
pontoon2 app. alt. of F. vingt-(et-)un ‘twenty-one’ (card game). XX.
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Cite this article
T. F. HOAD. "pontoon." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "pontoon." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-pontoon1.html T. F. HOAD. "pontoon." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-pontoon1.html |
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pontoon
pontoon •afternoon, attune, autoimmune, baboon, balloon, bassoon, bestrewn, boon, Boone, bridoon, buffoon, Cameroon, Cancún, cardoon, cartoon, Changchun, cocoon, commune, croon, doubloon, dragoon, dune, festoon, galloon, goon, harpoon, hoon, immune, importune, impugn, Irgun, jejune, June, Kowloon, lagoon, lampoon, loon, macaroon, maroon, monsoon, moon, Muldoon, noon, oppugn, picayune, platoon, poltroon, pontoon, poon, prune, puccoon, raccoon, Rangoon, ratoon, rigadoon, rune, saloon, Saskatoon, Sassoon, Scone, soon, spittoon, spoon, swoon, Troon, tune, tycoon, typhoon, Walloon
•fortune, misfortune
•vodun • veldskoen • honeymoon
•forenoon • tablespoon • teaspoon
•soupspoon • dessertspoon • Neptune
•tribune • triune • opportune
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Cite this article
"pontoon." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "pontoon." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O233-pontoon.html "pontoon." Oxford Dictionary of Rhymes. 2007. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-pontoon.html |
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