A guillotine lock is a type of

canal lock A lock is a device used for raising and lowering boats, ships and other watercraft between stretches of water of different levels on river and canal waterways. The distinguishing feature of a lock is a chamber in a permanently fixed position i ...

. The lock itself operates on the same principle as any normal pound lock, but is unusual in that each gate is a single piece, usually of

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

, that slides vertically upwards when opened to allow a boat to traverse underneath. The resemblance to the French

guillotine A guillotine ( ) is an apparatus designed for effectively carrying out executions by Decapitation, beheading. The device consists of a tall, upright frame with a weighted and angled blade suspended at the top. The condemned person is secur ...

is obvious. Guillotine locks are relatively uncommon, but many are found on the waterways of

East Anglia East Anglia is an area of the East of England, often defined as including the counties of Norfolk, Suffolk and Cambridgeshire, with parts of Essex sometimes also included. The name derives from the Anglo-Saxon kingdom of the East Angles, ...

. The advantages over the more traditional design are that the lock occupies less space, does not require room to swing open, and is quicker to fabricate and install. It also acts as a tidal lock, able to hold back water whichever side is higher, and can function as a stop lock (for example, Lifford Lane stop lock near Kings Norton Junction). It is mechanically more complex, however, requiring the use of a

gantry A gantry is an overhead bridge-like structure supporting equipment such as a crane, signals, or cameras. Devices and structures *Gantry (medical), cylindrical scanner assembly used for medical 3D-imaging or treatment *Gantry (transport), an over ...

and overhead lifting gear. A significantly larger one can be found at the northern terminus of the Maas-Waal Canal, between

Nijmegen Nijmegen ( , ; Nijmeegs: ) is the largest city in the Dutch province of Gelderland and the ninth largest of the Netherlands as a whole. Located on the Waal River close to the German border, Nijmegen is one of the oldest cities in the ...

and Weurt in the

Netherlands , Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...

. It demonstrates their use when the water level on the outside, the river

Waal WAAL (99.1 FM broadcasting, FM; "The Whale") is a commercial radio, commercial radio station licensed to Binghamton, New York. It airs a classic rock radio format and is owned by Townsquare Media. WAAL is the oldest FM radio station continuou ...

in this case, may be both higher or lower than the canal level. Here, the water level on the river varies from about below to about above canal level. The four paddles for equalising the water level are clearly visible, but guillotine gates without paddles exist too. In those, the entire gate is lifted a little bit to allow water in or out of the chamber. The Weurt lock has an additional gate near the centre of the chamber. When only a few short boats want to go through the lock, they can use one half the chamber, saving water. Furthermore, when one of the gates is taken out of service for maintenance, the lock can still function at reduced capacity. When open, guillotine gates are completely out of the water, so they can be painted without removing them or draining the lock. Lock 17 Erie canal

References

* ''Birmingham's Canals'', Ray Shill, 1999, 2002, {{DEFAULTSORT:Guillotine Lock Locks (water navigation)

See also

References