A trapdoor is a sliding or hinged door in a floor or ceiling. It is traditionally small in size. It was invented to facilitate the hoisting of grain up through mills, however, its list of uses has grown over time. The trapdoor has played a pivotal function in the operation of the

gallows A gallows (or scaffold) is a frame or elevated beam, typically wooden, from which objects can be suspended (i.e., hung) or "weighed". Gallows were thus widely used to suspend public weighing scales for large and heavy objects such as sacks ...

cargo ships A cargo ship or freighter is a merchant ship that carries cargo, goods, and materials from one port to another. Thousands of cargo carriers ply the world's seas and oceans each year, handling the bulk of international trade. Cargo ships are usu ...

, trains booby traps,and more recently theatre and films.

History

Originally, trapdoors were sack traps in mills, and allowed the sacks to pass up through the mill while naturally falling back to a closed position. Many buildings with flat

roof A roof ( : roofs or rooves) is the top covering of a building, including all materials and constructions necessary to support it on the walls of the building or on uprights, providing protection against rain, snow, sunlight, extremes of temp ...

s have hatches that provide access to the roof. On

ship A ship is a large watercraft that travels the world's oceans and other sufficiently deep waterways, carrying cargo or passengers, or in support of specialized missions, such as defense, research, and fishing. Ships are generally distinguishe ...

s, hatches—usually not flush, and never called trapdoors—provide access to the deck. Cargo ships, including

bulk carrier A bulk carrier or bulker is a merchant ship specially designed to transport unpackaged bulk cargo — such as grains, coal, ore, steel coils, and cement — in its cargo holds. Since the first specialized bulk carrier was built in 1852, ec ...

s, have large hatches for access to the

holds A hold (abbreviated HLD, H or HD) is awarded to a relief pitcher who meets the following three conditions: :1. Enters the game in a save (baseball), save situation; that is, when all of the following three conditions apply: :: (a) He appears i ...

Gallows

Most 19th- and early 20th-century

featured a trapdoor, usually with two flaps. The victim will be placed at the join. The edge of a trapdoor farthest from the hinge accelerates faster than gravity, so that the prisoner does not hit the flaps but falls freely.

Coffins

In 1784, the reusable economy coffin was mandated by

Joseph II, Holy Roman Emperor Joseph II (German: Josef Benedikt Anton Michael Adam; English: ''Joseph Benedict Anthony Michael Adam''; 13 March 1741 – 20 February 1790) was Holy Roman Emperor from August 1765 and sole ruler of the Habsburg lands from November 29, 1780 unt ...

. The coffins had a trapdoor in their base. The coffin would be lowered into the grave and a lever operated that opened the trapdoor, allowing the body to fall to the bottom of the grave.

Railways

The term trapdoor also refers to a plate in the entry vestibule of a passenger railcar that permits access to high-level platforms when lying flat against the floor of the car, and which can be flipped open to expose steps for accessing ground-level platforms. Many American commuter railroads which operate the

Comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or Coma (cometary), coma, and sometimes also a Comet ta ...

railcars made by Bombardier have trapdoors to accommodate passengers boarding and alighting on both high-level and ground-level platforms.

Amtrak The National Railroad Passenger Corporation, doing business as Amtrak () , is the national passenger railroad company of the United States. It operates inter-city rail service in 46 of the 48 contiguous U.S. States and nine cities in Canada ...

's Viewliner, Amfleet, and Horizon railcar fleets all have trapdoors.

Biology

Trapdoor spider Trapdoor spider is a common name that is used to refer to various spiders from several different groups that create burrows with a silk-hinged trapdoor to help them ambush prey. Several families within the infraorder Mygalomorphae contain trapdo ...

s hide in an underground nest they line with their silk, and then conceal it with a hinged silk lid, the trapdoor.

Star traps in theatre

In theatrical use, "star traps" allowed explosively fast appearances on stage, such as

jinn Jinn ( ar, , ') – also romanized as djinn or anglicized as genies (with the broader meaning of spirit or demon, depending on sources) – are invisible creatures in early pre-Islamic Arabian religious systems and later in Islamic my ...

appearing in a puff of smoke.

Fiction

Trapdoors are occasionally used as hidden doors in fiction, as entrances to secret passageways, dungeons, or to secret

tunnel A tunnel is an underground passageway, dug through surrounding soil, earth or rock, and enclosed except for the entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube cons ...

s. They also appear as literal traps into which a hapless pedestrian may fall if they happen to step on one. Other types of doors or other objects are also sometimes used as hidden doors. A trapdoor features in a late scene of the 1963 film '' Charade''.

Cary Grant Cary Grant (born Archibald Alec Leach; January 18, 1904November 29, 1986) was an English-American actor. He was known for his Mid-Atlantic accent, debonair demeanor, light-hearted approach to acting, and sense of comic timing. He was one o ...

's character releases a trapdoor in the stage of a theatre to save

Audrey Hepburn Audrey Hepburn (born Audrey Kathleen Ruston; 4 May 1929 – 20 January 1993) was a British actress and humanitarian. Recognised as both a film and fashion icon, she was ranked by the American Film Institute as the third-greatest female screen ...

's character from Walter Matthau's character.

References

External links

{{Commons category-inline, Trapdoors Doors Parts of a theatre