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557:, is a narrow horizontal ledge protruding a short way into the chamber from below the upper gates. Allowing the rear of the boat to "hang" on the cill is the main danger when descending a lock, and the position of the forward edge of the cill is usually marked on the lock side by a white line. The edge of the cill is usually curved, protruding less in the center than at the edges. In some locks, there is a piece of oak about 9 in (23 cm) thick which protects the solid part of the lock cill. On the Oxford Canal it is called a babbie; on the Grand Union Canal it is referred to as the cill bumper. Some canal operation authorities, primarily in the United States and Canada, call the ledge a
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1381:. The soldiers at one double slipway, he discovered, had plotted with bandits to wreck heavy imperial barges so that they could steal the spilled grain. In 984 Qiao installed a pair of sluice-gates two hundred and fifty feet apart, the entire structure roofed over like a building. By siting two staunch gates so close to one another, Qiao had created a short stretch of canal, effectively a pound-lock, filled from the canal above by raising individual wooden baulks in the top gate and emptied into the canal below by lowering baulks in the top gate and raising ones in the lower.
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involves a concentrated burst of effort, rather than a continually interrupted journey; a lock keeper may be stationed to help crews through the flight quickly; and where water is in short supply, a single pump can recycle water to the top of the whole flight. The need for a flight may be determined purely by the lie of the land, but it is possible to group locks purposely into flights by using cuttings or embankments to "postpone" the height change. Examples: Caen Hill locks,
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1004:"Flight" is not synonymous with "Staircase" (see below). A set of locks is only a staircase if successive lock chambers share a gate (i.e. do not have separate top and bottom gates with a pound between them). Most flights are not staircases, because each chamber is a separate lock (with its own upper and lower gates), there is a navigable pound (however short) between each pair of locks, and the locks are operated in the conventional way.
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allowing water to run to waste from the sump to a lower stream or drain, or (less wastefully) by pumping water back up to the canal. Particularly in the two-chamber type, there would be a need for a bypass culvert, to allow water to move along the interrupted pound and so supply locks further down the canal. In the case of the single-chamber type, this can be achieved by keeping the lock full and leaving the gates open while not in use.
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on river navigations in the early 18th century before the advent of canals in
Britain. The sides of the turf-lock are sloping so, when full, the lock is quite wide. Consequently, this type of lock needs more water to operate than vertical-sided brick- or stone-walled locks. On British canals and waterways most turf-sided locks have been subsequently rebuilt in brick or stone, and so only a few good examples survive, such as at
1115:"5-rise" and the "3-rise") ensure that there are no untoward events and that boats are moved through as speedily and efficiently as possible. Such expertise permits miracles of boat balletics: boats travelling in opposite directions can pass each other halfway up the staircase by moving sideways around each other; or at peak times, one can have all the chambers full simultaneously with boats travelling in the same direction.
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is, to open and shut the paddles a few times to create some waves, to help him get off the bank where he was stuck. If boats ran aground (from being overloaded) they sometimes asked passing crews to tell the upstream lock to give them an extra heavy swell, which consisted of opening all the paddles on the lock gate, creating a surge that affected the whole pound below.
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the water never left the chamber, and using the lock wasted no water. Instead, the boat entered the box and was sealed in by the door closing behind it, and the box itself was moved up or down through the water. When the box was at the bottom of the chamber, it was under almost 60 feet (18.3 m) of water – at a pressure of three
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the bottom gate). As there is no intermediate pound, a chamber can only be filled by emptying the one above, or emptied by filling the one below: thus the whole staircase has to be full of water (except for the bottom chamber) before a boat starts to ascend, or empty (except for the top chamber) before a boat starts to descend.
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boat to follow a previous one going in the same direction. Partly for this reason staircase locks such as
Grindley Brook, Foxton, Watford and Bratch are supervised by lockkeepers, at least during the main cruising season, they normally try to alternate as many boats up, followed by down as there are chambers in the flight.
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wave along the canal) or completely emptying an intermediate chamber (although this shows that a staircase lock can be used as an emergency dry dock). To avoid these mishaps, it is usual to have the whole staircase empty before starting to descend, or full before starting to ascend, apart from the initial chamber.
745:, there was a danger of injury when operating the paddles: water, on reaching a certain position, would push the paddles with a force which could tear the windlass (or handle) out of one's hands, or if one was standing in the wrong place, could knock one into the canal, leading to injuries and drownings.
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has a fall of 12.7 metres (42 ft) and has eight tanks linked in pairs to the lock chamber. As the lock is emptied water is run into each chamber in turn, for filling the water is released from the chambers thus saving the waste of a complete lockfull of water. An earlier attempt at a shaft lock
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in
England. In this underwater lift, the chamber was 80 ft (24.4 m) long and 60 ft (18.3 m) deep and contained a completely enclosed wooden box big enough to take a barge. This box moved up and down in the 60 ft (18.3 m) deep pool of water. Apart from inevitable leakage,
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became the world's largest lock by surface area. The lock is 500 m (1,600 ft) long, 70 m (230 ft) wide and has sliding lock gates creating a usable depth of 18 m (59 ft). The size of locks cannot be compared without considering the difference in water level that they are
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Operation of a staircase is more involved than a flight. Inexperienced boaters may find operating staircase locks difficult. The key worries (apart from simply being paralysed with indecision) are either sending down more water than the lower chambers can cope with (flooding the towpath, or sending a
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A drop lock can consist of two conventional lock chambers leading to a sump pound, or a single long chamber incorporating the sump – although the term properly applies only to the second case. As the pounds at either end of the structure are at the same height, the lock can only be emptied either by
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As with a flight, it is possible on a broad canal for more than one boat to be in a staircase at the same time, but managing this without waste of water requires expertise. On
English canals, a staircase of more than two chambers is usually staffed: the lockkeepers at Bingley (looking after both the
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To economise, especially where good stone would be prohibitively expensive or difficult to obtain, composite locks were made, i.e. they were constructed using rubble or inferior stone, dressing the inside walls of the lock with wood, so as not to abrade the boats. This was done, for instance, on the
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was caused by opening suddenly the paddle valves in the lock gates, or when emptying a lock. To help boats traveling downstream exit a lock, the locksman would sometimes open the paddles to create a swell, which would help "flush" the boat out of the lock. A boatsman might ask for a back swell, that
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The distance between the two locks was rather more than 50 paces, and the whole space was covered with a great roof like a shed. The gates were 'hanging gates'; when they were closed the water accumulated like a tide until the required level was reached, and then when the time came it was allowed to
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This is similar to a shaft lock, but having the shaft built on an incline. Boats are moored to floating bollards which guide them along the shaft as it fills or empties. The "Diagonal Lock
Advisory Group" has identified several sites in Britain where the new design could be installed, either on new
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A turf-sided lock is an early form of canal lock design that uses earth banks to form the lock chamber, subsequently attracting grasses and other vegetation, instead of the now more familiar and widespread brick, stone, or concrete lock wall constructions. This early lock design was most often used
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One striking difference in using a staircase of either type (compared with a single lock, or a flight) is the best sequence for letting boats through. In a single lock (or a flight with room for boats to pass) boats should ideally alternate in direction. In a staircase, however, it is quicker for a
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and its drunk captain. That boat was already leaking; the crew, having partially pumped the water out, entered Lock 74, moving in front of another boat. Because they failed to snub the boat, it crashed into and knocked out the downstream gates. The outrush of water from the lock caused the upstream
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On the Erie Canal, some loaded boats needed a swell to get out of the lock. Particularly lumber boats, being top heavy, would list to one side and get stuck in the lock, and needed a swell to get them out. Some lockkeepers would give a swell to anyone to help them on the way, but some would ask for
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in
Scotland. This lock, of the single-chamber type, was incorporated during the restoration of the canal, to allow the replacement of a swing bridge (on a busy A road) by a fixed bridge, and so answer criticisms that the restoration of the canal would cause frequent interruptions of the heavy road
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interchangeably: because of the absence of intermediate pounds, operating a staircase is very different from operating a flight. It can be more useful to think of a staircase as a single lock with intermediate levels (the top gate is a normal top gate, and the intermediate gates are all as tall as
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On horse-drawn and mule-drawn canals, snubbing posts were used to slow or stop a boat in the lock. A 200-ton boat moving at a few miles an hour could destroy the lock gate. To prevent this, a rope was wound around the snubbing post as the boat entered the lock. Pulling on the rope slowed the boat,
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Boaters approaching a lock are usually pleased to meet another boat coming towards them, because this boat will have just exited the lock on their level and therefore set the lock in their favour – saving about 5 to 10 minutes. However, this is not true for staircase locks, where it is quicker for
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If the lock were empty, the boat would have had to wait 5 to 10 minutes while the lock was filled. For a boat travelling upstream, the process is reversed; the boat enters the empty lock, and then the chamber is filled by opening a valve that allows water to enter the chamber from the upper level.
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When variable conditions meant that a higher water level in the new canal could not be guaranteed, then the older company would also build a stop lock (under its own control, with gates pointing towards its own canal) which could be closed when the new canal was low. This resulted in a sequential
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worked on this project. There can also be water savings: the locks may be of different sizes, so that a small boat does not need to empty a large lock; or each lock may be able to act as a side pond (water-saving basin) for the other. In this latter case, the word used is usually "twinned": here
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Looking superficially similar to the caisson lock is the shaft lock. Shaft locks consist of a deep shaft with conventional upper gates. The lower gates are reached through a short tunnel. The gates only close off this approach tunnel so do not have to reach the full height of the lock. Notable
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Loosely, a flight of locks is simply a series of locks in close-enough proximity to be identified as a single group. For many reasons, a flight of locks is preferable to the same number of locks spread more widely: crews are put ashore and picked up once, rather than multiple times; transition
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indicating the possibility of saving water by synchronising the operation of the chambers so that some water from the emptying chamber helps to fill the other. This facility has long been withdrawn on the
English canals, although the disused paddle gear can sometimes be seen, as at
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The Erie Canal management did not like swelling for two reasons. First, it used too much water lowering the water on the pound above sometimes causing boats to run aground. In addition, it raised the water level on the pound below, causing some boats to strike bridges or get stuck.
1346:, or staunch, was to provide an upper gate (or pair of gates) to form an intermediate "pound" which was all that need be emptied when a boat passed through. This type of lock, called a pound lock was known in Imperial China and ancient Europe and was used by Greek engineers in the
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had been made at Trollhättan in Sweden on the line of the present Göta canal. The fall would have been 16 metres (52 ft), astonishing in 1749. However the approach tunnel proved to be unusable in times of flood and the shaft lock was replaced by a 2-rise staircase in 1768.
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locks near
Limerick on the Shannon navigation in Ireland have a rise of 100 feet (30 m). The upper chamber rises 60 feet (18 m) and is connected to the lower chamber by a tunnel, which when descending does not become visible until the chamber is nearly empty.
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However, some flights include (or consist entirely of) staircases. On the Grand Union (Leicester) Canal, the
Watford flight consists of a four-chamber staircase and three separate locks; and the Foxton flight consists entirely of two adjacent 5-chamber staircases.
514:, which both have a rise of nearly 20 feet (6.1 m). Both locks are amalgamations of two separate locks, which were combined when the canals were restored to accommodate changes in road crossings. By comparison, the Carrapatelo and Valeira locks on the
1440:. The plane enabled wide-beam boats to bypass the flight of ten narrow locks, but failure to make improvements at the other end of the arm and high running costs led to its early demise. There are plans to restore it, and some funding has been obtained.
973:, a considerable engineering feat in the nineteenth century. While Lockport today has two large steel locks, half of the old twin stair acts as an emergency spillway and can still be seen, with the original lock gates having been restored in early 2016.
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In an "apparent" staircase the chambers still have common gates, but the water does not pass directly from one chamber to the next, going instead via side ponds. This means it is not necessary to ensure that the flight is full or empty before starting.
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to empty or fill the chamber as required. This is usually a simple valve (traditionally, a flat panel (paddle) lifted by manually winding a rack and pinion mechanism) which allows water to drain into or out of the chamber. Larger locks may use
1511:, north London. Here the motivation was, again, water supply problems. The company insisted on various modifications to Congreve's design; the resulting installation proved to be unsatisfactory, and was soon replaced by conventional locks.
1369:(960–1279 CE). The Songshi or History of the Song Dynasty, volume 307, biography 66, records how Qiao Weiyue, a high-ranking tax administrator, was frustrated at the frequent losses incurred when his grain barges were wrecked on the
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A "real" staircase can be thought of as a "compressed" flight, where the intermediate pounds have disappeared, and the upper gate of one lock is also the lower gate of the one above it. However, it is incorrect to use the terms
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gates to slam shut, breaking them also, and sending a cascade of water over the boat, sinking it. This suspended navigation on the canal for 48 hours until the lock gates could be replaced and the boat removed from the lock.
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318:. The gates in each pair close against each other at an 18° angle to approximate an arch against the water pressure on the "upstream" side of the gates when the water level on the "downstream" side is lower.
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has three sets of double locks. Doubling gives advantages in speed, avoiding hold-ups at busy times and increasing the chance of a boat finding a lock set in its favour. The
Belgian company
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Gates are the watertight doors which seal off the chamber from the upper and lower pounds. Each end of the chamber is equipped with a gate, or pair of half-gates, traditionally made of
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The whole operation will usually take between 10 and 20 minutes, depending on the size of the lock and whether the water in the lock was originally set at the boat's level.
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that raise and lower the sluices in their raised position. To the right is one of two pedestals which are used to operate the sluices, as well as open and close the gates.
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302:: Ptolemy II is credited by some for being the first to solve the problem of keeping the Nile free of salt water when his engineers invented the lock around 274/273 BC.
431:(often a pair of "pointing" half-gates) at each end of the chamber. A gate is opened to allow a boat to enter or leave the chamber; when closed, the gate is watertight.
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river in Portugal, which are 279 feet (85 m) long and 39 feet (12 m) wide, have maximum lifts of 115 and 108 feet (35 and 33 m) respectively. The two
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traffic. It can be emptied by pumping – but as this uses a lot of electricity the method used when water supplies are adequate is to drain the lock to a nearby
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connecting the upper and lower canals, and large enough to enclose one or more boats. The position of the chamber is fixed, but its water level can vary.
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includes a double five-step staircase for large ships, and a ship lift for vessels of less than 3000 metric tons. Examples of "apparent" staircases are
884:, one connected by chains to open the gate and another to draw it closed. By 1968 these had been replaced by hydraulic power acting through steel rams.
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examples have been built at Saint Denis (Paris, France), Horin (near Melnik, Czech Republic) and Anderten (Hannover Germany). The shaft lock at Minden
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are often taken to counteract this. Navigation locks have also potential to be operated as fishways to provide increased access for a range of biota.
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On the Chesapeake and Ohio Canal, the lockkeepers were required to remove the windlasses from all lock paddles at night, to prevent unauthorized use.
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A plan and side view of a generic, empty canal lock. A lock chamber separated from the rest of the canal by an upper pair and a lower pair of mitre
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While the concept has been suggested in a number of cases, the only example in the world of a drop lock that has actually been constructed is at
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gates which stopped the water flow regardless of which canal was higher. These gates have been permanently open since nationalisation.
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Berendrecht Lock (right) and Zandvliet Lock (left), located at the entrance to the Port of Antwerp (top) from the Scheldt (foreground)
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969:, was also a doubled set of locks. Five twinned locks allowed east- and west-bound boats to climb or descend the 60 feet (18 m)
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inches (6.4 cm) in diameter and about 60 feet (18 meters) long was typically used on the Erie Canal to snub a boat in a lock.
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Where a very steep gradient has to be climbed, a lock staircase is used. There are two types of staircase, "real" and "apparent".
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could be raised and lowered in counterbalance by the movement of compressed air from one caisson to the other. In about 1817 the
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The principle of operating a lock is simple. For instance, if a boat travelling downstream finds the lock already full of water:
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2335:"Can navigation locks be used to help migratory fishes with poor swimming performance pass tidal barrages? A test with lampreys"
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A series of photos of the Canadian Locks in Sault Ste. Marie to illustrate a drop of about 22 ft (6.7 m) in a lock
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at both ends that control the level of water in the pound. In contrast, an earlier design with a single gate was known as a
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were converted to staircase locks after low water levels hindered navigation over the bottom cill at all but the higher
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Doubled locks. Left lock has boat in it, right lock (center of drawing) is empty. This is on the Erie Canal at Lockport.
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There are no working waterway inclined planes in the UK at the moment, but the remains of a famous one can be seen at
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The construction of locks (or weirs and dams) on rivers obstructs the passage of fish. Some fish such as lampreys,
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to cross land that is not level. Later canals used more and larger locks to allow a more direct route to be taken.
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138:. The distinguishing feature of a lock is a fixed chamber in which the water level can be varied; whereas in a
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2607:""Nederlanders kunnen niet rekenen": waarom Antwerpen en niet Amsterdam de grootste zeesluis ter wereld heeft"
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Snubbing a boat to keep it from hitting the downstream gates. Note the rope wrapped around the snubbing post.
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has a fall of at least 23 m (75 ft), the Leerstetten, EckersmĂĽhlen and Hilpoltstein locks on the
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One incident, which took place in June 1873 on the Chesapeake and Ohio Canal, involved the boat the
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waterways or canals under restoration. Projects under consideration include the restoration of the
1487:), but it had various engineering problems and the design was not put into use on the Coal Canal.
1419:, reopened in 2011, has a flight of three locks at Hanbury which all have operational side ponds.
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in 1813 patented a "hydro-pneumatic double balance lock" in which two adjacent locks containing
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is the change in water-level in the lock. The two deepest locks on the English canal system are
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2003:
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Berossus and Genesis, Manetho and Exodus: Hellenistic Histories and the Date of the Pentateuch
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pair of locks, with gates pointing in opposite directions: one example was at Hall Green near
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4. Bottom gates are closed, bottom paddles closed, top paddles opened, lock starts to fill
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on the River Thames, with its chamber nearly filled. Visible on top of the gates are the
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in France. This serves as a lock on the main line of the canal and allows access to the
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The water level could differ by 4 or 5 feet (1.2 or 1.5 m) at each lock and in the
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954:. Elsewhere they are still in use; a pair of twinned locks was opened in 2014 on the
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Needham, Joseph; Lu, Gwei-Djen; Wang, Ling (1971). "Civil Engineering and Nautics".
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model view. A pair of five locking steps is at center with a ship lift to the left
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Collection of lock windlasses. Note: rakes are for clearing trash out of the lock.
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Model of early river pound lock, constructed in Lankheet water park, Netherlands
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Video footage of the unique Drop Lock at Dalmuir on the Forth & Clyde Canal
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Locks can be built side by side on the same waterway. This is variously called
868:, the gates and paddles are too large to be hand operated, and are operated by
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219:(960–1279 CE), having been pioneered by the Song politician and naval engineer
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2937:. ICOMOS (the International Council on Monuments and Sites). Archived from
1730:"Canals and inland waterways - Locks, Navigation, Engineering | Britannica"
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A valve is opened, this lowers the boat by draining water from the chamber.
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in the same port and still has the title for largest volume. In 2022 the
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Silva, S.; Lowry, M.; Macaya-Solis, C.; Byatt, B.; Lucas, M.C. (2017).
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A second French round lock can be found in the form of the now-disused
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267:, Netherlands. This pound lock serviced many ships at once in a large
2004:"Final Report of the International Commission for the Study of Locks"
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2397:"Governor Cuomo Announces Funding For Restoration of Lockport Locks"
1802:. Vol. 4:3. Cambridge: Cambridge University Press. p. 352.
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in Belgium took over the title of the world's largest lock from the
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2055:(Second ed.). Oxford, England: Oxford University Press. 1989.
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Bertola da Novate (c. 1410–1475) constructed 18 pound locks on the
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solved the problem of overcoming the difference in height through
1140:. The four gate stop lock near Kings Norton Junction, between the
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between stretches of water of different levels on river and canal
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for students with single and double flight locks and lesson plans
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On English canals, these reservoirs are called "side ponds". The
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is the level stretch of water between two locks (also known as a
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Canal lock and lock-keeper's cottage on the Aylesbury Arm of the
37:"Gate (water transport)" redirects here. Not to be confused with
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5. Lock is filling with water, lifting boat to the higher level
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2514:"Mitsubishi helps breath new life into important canal routes"
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2850:"History of the Caisson Lock On the Somersetshire Coal Canal"
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In medieval Europe a sort of pound lock was built in 1373 at
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boats to go through in convoy, and it also uses less water.
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Cameron, A.D. (2005). "10 Working the canal in the 1820s".
864:
On large modern canals, especially very large ones such as
298:
In Ancient Egypt, the river-locks was probably part of the
127:
123:
31:
2074:
1850:
1838:
1824:
1789:
260:
the level was raised in this way by 138 feet (42 m).
1884:
1365:
Pound locks were first used in medieval China during the
1294:
have a fall of 24.67 m (80.9 ft), each and the
799:
due to the friction of the rope against the post. A rope
718:
714:
578:
The cill exposed in the deep Pont de Flandre lock on the
227:
that had caused trouble and are mentioned by the Chinese
1507:
built one of these locks at the site of the present-day
2581:"Officiële opening van de grootste zeesluis ter wereld"
2149:. Syracuse, NY: Syracuse University Press. p. 39.
2110:. Syracuse, NY: Syracuse University Press. p. 38.
382:
The lock is emptied by draining its water downstream.
2634:(1950). "Three Canal Projects, Roman and Byzantine".
1462:
Around 1800 the use of caisson locks was proposed by
271:. Yet the first true pound lock was built in 1396 at
2280:
US Department of the Interior, National Park Service
2069:
Merriam-Webster Dictionary, definition of miter sill
1607:
1048:
Examples of famous "real" staircases in England are
447:
The entrance gates are opened and the boat moves in.
2880:"Congreve's Hydro-Pneumatic Canal Lift – A Humbug!"
2741:Smithett, Robin (April 2012). "A bit on the side".
912:
305:
1975:
849:Chesapeake and Ohio Canal with the locks near the
748:
406:
400:
392:
386:
378:
372:
364:
358:
350:
344:
150:, it is the chamber itself (usually then called a
456:The exit gates are opened and the boat moves out.
3085:
2964:World Canals: Inland Navigation Past and Present
2690:
2270:
240:(published in 1088), and fully described in the
215:Pound locks were first used in China during the
3032:(8th ed.). Imray Laurie Norie and Wilson.
2140:
2138:
2136:
725:). The most common arrangement, usually called
594:The balance beams typical of many locks on the
2824:Bath Royal Literary and Scientific Institution
1779:"7 of the World's Most Impressive Canal Locks"
1436:in Leicestershire on the Leicester arm of the
1168:The best known example of a round lock is the
1099:Instructions for descent of treble staircase,
1020:Staircase of four locks, dating from 1774, at
27:Device for raising and lowering boats or ships
2604:
1795:
1490:
376:The lock is filled with water from upstream.
2910:The Regent's Canal: London's Hidden Waterway
2133:
1495:Possibly inspired by Weldon's caisson lock,
1282:designed to operate under. For example, the
880:the lock gates were operated by man-powered
3027:
1895:
2784:"Foxton Inclined Plane Trust: Restoration"
2147:Canal Boatman My Life on Upstate Waterways
2108:Canal Boatman My Life on Upstate Waterways
1309:
484:
122:is a device used for raising and lowering
2605:van den Buijs, Dennis (26 January 2022).
2358:
900:go upstream to spawn. Measures such as a
3060:Interactive simulation of lock operation
2961:
2932:"The International Canal Monuments List"
2740:
2716:"British Waterways 'Waterscape' website"
2511:
1567:
1518:
1447:
1326:
1318:
1246:
1238:
1202:
1159:
1094:
1015:
980:
916:
828:
789:
752:
467:
309:
172:
106:
94:
75:
59:
43:
2995:
2766:, Volume 3, Harper Collins Publishers,
2459:
2434:
2307:
2144:
2105:
2062:
2031:. Irish Waterways History. 22 July 2009
1865:
1776:
1306:has a drop of 42 m (138 ft).
1056:. Two-rise staircases are more common:
733:sometime around the late 15th century.
204:today. A pound lock has a chamber with
14:
3086:
2854:The Somersetshire Coal Canal (Society)
1973:
1410:
324:Principle of operation of a pound lock
2630:
1128:, where the southern terminus of the
416:All pound locks have three elements:
223:in 984. They replaced earlier double
161:more easily navigable, or to allow a
2966:. David & Charles. p. 162.
1933:from the original on 4 January 2022.
859:
764:
1812:Needham, Volume 4, Part 3, 350-351.
1588:and the proposed new branch of the
1234:
24:
2929:
2312:(4 ed.). Edinburgh: Birlinn.
1821:Needham, Volume 4, Part 3, 351–52.
1384:
1335:on the Kennet & Avon Canal at
1148:was replaced in 1914 by a pair of
1011:
843:
25:
3135:
3048:
3030:Inland Waterways of Great Britain
2558:. Waterways World. Archived from
2173:. Seven Locks Press, 1983. p. 207
1915:from the original on 2 June 2023.
1799:Science and Civilisation in China
1777:Newcomb, Tim (13 December 2016).
1427:
785:
1624:
1610:
1563:
913:Doubled, paired or twinned locks
907:
689:
674:
659:
650:200-year-old paddle gear on the
643:
619:
587:
571:
564:
333:
306:Basic construction and operation
3020:
2989:
2980:
2955:
2923:
2902:
2872:
2842:
2812:
2801:
2776:
2757:
2734:
2708:
2699:
2681:
2672:
2637:American Journal of Archaeology
2624:
2598:
2573:
2548:
2527:
2505:
2484:
2415:
2389:
2375:
2326:
2301:
2264:
2243:
2215:
2206:
2185:
2176:
2163:
2124:
2099:
2042:
2021:
1996:
1967:
1937:
1919:
1901:
1870:. Bloomsbury 3PL. p. 236.
1859:
1856:Needham, Volume 4, Part 3, 358.
1847:Needham, Volume 4, Part 3, 357.
1835:Needham, Volume 4, Part 3, 351.
1443:
1422:
1405:
1314:
976:
887:
666:Water conservation gear on the
3124:Water transport infrastructure
3055:Deepest Canal Locks in England
1770:
1746:
1722:
1155:
1146:Worcester and Birmingham Canal
450:The entrance gates are closed.
13:
1:
2786:. Fipt.org.uk. Archived from
2512:voltimum (11 December 2002).
2360:10.1016/J.ECOLENG.2017.02.027
2029:"The ESB lock at Ardnacrusha"
1715:
1523:Entrance to Minden shaft lock
1514:
1342:The natural extension of the
1198:
1118:
965:The once-famous staircase at
824:
476:1–3. Boat enters 'empty' lock
340:For a boat going downstream:
168:
2282:. p. 15. Archived from
1866:Gmirkin, Russell E. (2006).
1665:Canals of the United Kingdom
668:Birmingham Canal Navigations
396:The lower gates are opened.
390:The upper gates are opened.
368:The upper gates are closed.
362:The lower gates are closed.
177:A pound lock on the Keitele–
7:
2678:Rappoport 1904, pp. 250-253
2383:"Zwillingsschleuse MĂĽnster"
2253:. Seven Locks Press, 1983,
1978:The Kennet & Avon Canal
1603:
330:For a boat going upstream:
10:
3140:
3028:Cumberlidge, Jane (2009).
2998:"Diagonal Lock – Overview"
2962:Hadfield, Charles (1986).
2467:"Canal lateral a la Loire"
2071:, Retrieved Jan. 28, 2015.
1909:"How do canal locks work?"
1754:"Different types of locks"
1491:Hydro-pneumatic canal lift
1455:
985:The flight of 16 locks at
409:
403:
395:
389:
381:
375:
367:
361:
354:The boat enters the lock.
353:
348:The boat enters the lock.
347:
291:canal system sponsored by
36:
29:
3064:this demonstration shows
2820:"The Somerset Coal Canal"
2764:Nicholson Waterways Guide
2424:, Ray Shill, 1999, 2002,
2271:Bearss, Edwin C. (1968).
2145:Garrity, Richard (1977).
2106:Garrity, Richard (1977).
2052:Oxford English Dictionary
1982:. Bath: Millstream Book.
1685:List of canals by country
1452:Operation of caisson lock
1142:Stratford-upon-Avon Canal
736:
473:Operation of a canal lock
410:The boat exits the lock.
404:The boat exits the lock.
339:
332:
329:
295:) between 1452 and 1458.
196:is most commonly used on
157:Locks are used to make a
56:in Hertfordshire, England
3094:Locks (water navigation)
2705:Schörner 2000, pp. 33–35
1189:Canal latéral à la Loire
721:but now usually made of
708:
681:Lock gate controls on a
561:(mitre sill in Canada).
526:
234:(1031–1095) in his book
154:) that rises and falls.
30:Not to be confused with
2996:Fogarty, Terry (2008).
2930:Hughes, Stephen (ed.).
2912:. Waterways World Ltd.
2908:Faulkner, Alan (2005):
2212:Garrity, Richard. p. 41
2182:Garrity, Richard. p. 40
1927:"Staircase Canal Locks"
1655:Canal & River Trust
1310:History and development
1292:Rhine–Main–Danube Canal
1252:Upper Mississippi River
652:Wiener Neustädter Kanal
544:
489:
485:Details and terminology
242:Chinese historical text
2986:Hadfield (1986) p. 55.
2687:Moore 1950, pp. 99–101
2339:Ecological Engineering
1974:Allsop, Niall (1987).
1758:canalrivertrust.org.uk
1576:
1524:
1453:
1354:(284 to 246 BC), when
1339:
1324:
1258:
1244:
1211:
1165:
1138:Trent and Mersey Canal
1103:
1025:
993:
922:
840:
795:
758:
481:
319:
285:Naviglio di Bereguardo
254:
189:
115:
104:
92:
73:
57:
3073:Interactive lock game
3066:guillotine-type gates
2535:"Clydebank Drop Lock"
2273:"The Composite Locks"
1675:Hydraulic engineering
1618:United Kingdom portal
1571:
1522:
1505:Regents Canal Company
1451:
1400:Kennet and Avon Canal
1348:Canal of the Pharaohs
1330:
1322:
1250:
1242:
1224:Forth and Clyde Canal
1206:
1163:
1098:
1019:
991:Kennet and Avon Canal
984:
920:
838:
793:
778:money for the swell.
756:
749:Windlass ("lock key")
630:, a beam lock on the
504:Kennet and Avon Canal
471:
313:
300:Canal of the Pharaohs
249:
176:
113:Saint Lawrence Seaway
111:Iroquois Lock on the
110:
98:
79:
63:
47:
2890:on 27 September 2013
2632:Moore, Frank Gardner
2310:The Caledonian Canal
1929:. Droitwich Canals.
1547:52.30639°N 8.91972°E
1185:Écluse des Lorraines
1066:Driffield Navigation
1062:Struncheon Hill Lock
701:hydraulic mechanisms
247:(compiled in 1345):
148:canal inclined plane
3004:on 15 February 2017
2830:on 14 November 2006
2696:Froriep 1986, p. 46
2492:"Dalmuir Drop Lock"
2422:Birmingham's Canals
2351:2017EcEng.102..291S
1955:on 16 November 2007
1660:Canals of Amsterdam
1650:Channel (geography)
1543: /
1468:Somerset Coal Canal
1411:Water saving basins
326:
3104:Chinese inventions
2860:on 11 October 2006
2644:(2): 97–111 (99).
2473:. grehanman guides
2448:. grehanman guides
2249:Kytle, Elizabeth.
2191:Kytle, Elizabeth.
2169:Kytle, Elizabeth.
1734:www.britannica.com
1645:Canal Safety Gates
1577:
1525:
1501:pneumatic caissons
1454:
1340:
1325:
1259:
1256:Lock and Dam No. 6
1245:
1212:
1166:
1130:Macclesfield Canal
1104:
1101:Chesterfield Canal
1026:
994:
971:Niagara Escarpment
967:Lockport, New York
956:Dortmund–Ems Canal
923:
876:equipment. On the
841:
796:
759:
729:, was invented by
482:
322:
320:
190:
116:
105:
93:
74:
64:Lock on the River
58:
3039:978-1-84623-010-3
2587:. 26 January 2022
2585:Port of Amsterdam
2259:978-0-932020-13-0
2251:Home on the Canal
2193:Home on the Canal
2171:Home on the Canal
1949:Images of England
1911:. ABC Boat Hire.
1783:Popular Mechanics
1690:List of waterways
1590:Grand Union Canal
1552:52.30639; 8.91972
1438:Grand Union Canal
1396:Monkey Marsh Lock
1333:Monkey Marsh Lock
1279:Port of Amsterdam
1275:IJmuiden sea lock
1187:, connecting the
1134:Hall Green Branch
860:Powered operation
836:
765:Swell or swelling
731:Leonardo da Vinci
580:Canal Saint-Denis
414:
413:
237:Dream Pool Essays
50:Grand Union Canal
16:(Redirected from
3131:
3043:
3014:
3013:
3011:
3009:
3000:. Archived from
2993:
2987:
2984:
2978:
2977:
2959:
2953:
2952:
2950:
2949:
2943:
2936:
2927:
2921:
2906:
2900:
2899:
2897:
2895:
2886:. Archived from
2876:
2870:
2869:
2867:
2865:
2856:. Archived from
2846:
2840:
2839:
2837:
2835:
2826:. Archived from
2816:
2810:
2805:
2799:
2798:
2796:
2795:
2780:
2774:
2761:
2755:
2754:
2738:
2732:
2731:
2729:
2727:
2718:. Archived from
2712:
2706:
2703:
2697:
2694:
2688:
2685:
2679:
2676:
2670:
2669:
2628:
2622:
2621:
2619:
2617:
2602:
2596:
2595:
2593:
2592:
2577:
2571:
2570:
2568:
2567:
2552:
2546:
2545:
2543:
2542:
2531:
2525:
2524:
2522:
2520:
2509:
2503:
2502:
2500:
2498:
2488:
2482:
2481:
2479:
2478:
2471:Afloat in France
2463:
2457:
2456:
2454:
2453:
2446:Afloat in France
2438:
2432:
2419:
2413:
2412:
2410:
2408:
2403:. 17 August 2015
2393:
2387:
2386:
2379:
2373:
2372:
2362:
2330:
2324:
2323:
2305:
2299:
2298:
2296:
2294:
2288:
2277:
2268:
2262:
2247:
2241:
2240:
2238:
2236:
2227:
2219:
2213:
2210:
2204:
2189:
2183:
2180:
2174:
2167:
2161:
2160:
2142:
2131:
2128:
2122:
2121:
2103:
2097:
2096:
2094:
2093:
2086:Encyclopedia.com
2078:
2072:
2066:
2060:
2059:
2046:
2040:
2039:
2037:
2036:
2025:
2019:
2018:
2016:
2014:
2000:
1994:
1993:
1981:
1971:
1965:
1964:
1962:
1960:
1951:. Archived from
1941:
1935:
1934:
1923:
1917:
1916:
1905:
1899:
1896:Cumberlidge 2009
1893:
1882:
1881:
1863:
1857:
1854:
1848:
1845:
1836:
1833:
1822:
1819:
1813:
1810:
1804:
1803:
1793:
1787:
1786:
1774:
1768:
1767:
1765:
1764:
1750:
1744:
1743:
1741:
1740:
1726:
1634:
1632:Transport portal
1629:
1628:
1620:
1615:
1614:
1613:
1573:Three Gorges Dam
1558:
1557:
1555:
1554:
1553:
1548:
1544:
1541:
1540:
1539:
1536:
1497:William Congreve
1271:Berendrecht Lock
1235:Very large locks
1086:Leicester Branch
1074:Three Gorges Dam
1012:Staircase locks
878:Caledonian Canal
837:
812:
811:
807:
804:
693:
678:
663:
647:
623:
591:
575:
337:
327:
321:
293:Francesco Sforza
81:Three Gorges Dam
21:
3139:
3138:
3134:
3133:
3132:
3130:
3129:
3128:
3084:
3083:
3051:
3046:
3040:
3023:
3018:
3017:
3007:
3005:
2994:
2990:
2985:
2981:
2974:
2960:
2956:
2947:
2945:
2941:
2934:
2928:
2924:
2907:
2903:
2893:
2891:
2878:
2877:
2873:
2863:
2861:
2848:
2847:
2843:
2833:
2831:
2818:
2817:
2813:
2806:
2802:
2793:
2791:
2782:
2781:
2777:
2762:
2758:
2743:Waterways World
2739:
2735:
2725:
2723:
2722:on 3 April 2012
2714:
2713:
2709:
2704:
2700:
2695:
2691:
2686:
2682:
2677:
2673:
2629:
2625:
2615:
2613:
2603:
2599:
2590:
2588:
2579:
2578:
2574:
2565:
2563:
2554:
2553:
2549:
2540:
2538:
2533:
2532:
2528:
2518:
2516:
2510:
2506:
2496:
2494:
2490:
2489:
2485:
2476:
2474:
2465:
2464:
2460:
2451:
2449:
2442:"Canal du Midi"
2440:
2439:
2435:
2420:
2416:
2406:
2404:
2395:
2394:
2390:
2381:
2380:
2376:
2331:
2327:
2320:
2306:
2302:
2292:
2290:
2289:on July 3, 2007
2286:
2275:
2269:
2265:
2248:
2244:
2234:
2232:
2225:
2221:
2220:
2216:
2211:
2207:
2190:
2186:
2181:
2177:
2168:
2164:
2157:
2143:
2134:
2129:
2125:
2118:
2104:
2100:
2091:
2089:
2080:
2079:
2075:
2067:
2063:
2048:
2047:
2043:
2034:
2032:
2027:
2026:
2022:
2012:
2010:
2002:
2001:
1997:
1990:
1972:
1968:
1958:
1956:
1943:
1942:
1938:
1925:
1924:
1920:
1907:
1906:
1902:
1894:
1885:
1878:
1864:
1860:
1855:
1851:
1846:
1839:
1834:
1825:
1820:
1816:
1811:
1807:
1794:
1790:
1775:
1771:
1762:
1760:
1752:
1751:
1747:
1738:
1736:
1728:
1727:
1723:
1718:
1700:Water resources
1630:
1623:
1616:
1611:
1609:
1606:
1582:Lancaster Canal
1566:
1551:
1549:
1545:
1542:
1537:
1534:
1532:
1530:
1529:
1517:
1493:
1460:
1446:
1430:
1425:
1417:Droitwich Canal
1413:
1408:
1387:
1385:Turf-sided lock
1331:The turf-sided
1317:
1312:
1267:Port of Antwerp
1263:Kieldrecht Lock
1254:
1237:
1201:
1170:Agde Round Lock
1164:Agde Round Lock
1158:
1150:guillotine lock
1136:of the earlier
1121:
1058:Snakeholme Lock
1014:
979:
943:SBE Engineering
915:
910:
890:
862:
853:. and also the
846:
844:Composite locks
829:
827:
809:
805:
802:
800:
788:
767:
751:
739:
711:
704:
694:
685:
679:
670:
664:
655:
648:
639:
624:
615:
592:
583:
576:
567:
553:, also spelled
547:
529:
492:
487:
479:
477:
475:
308:
279:, Belgium. The
187:Central Finland
171:
42:
35:
28:
23:
22:
15:
12:
11:
5:
3137:
3127:
3126:
3121:
3119:Types of gates
3116:
3111:
3106:
3101:
3096:
3082:
3081:
3076:
3070:
3057:
3050:
3049:External links
3047:
3045:
3044:
3038:
3024:
3022:
3019:
3016:
3015:
2988:
2979:
2972:
2954:
2922:
2901:
2871:
2841:
2811:
2800:
2775:
2756:
2733:
2707:
2698:
2689:
2680:
2671:
2650:10.2307/500198
2623:
2597:
2572:
2547:
2537:. Gentles.info
2526:
2504:
2483:
2458:
2433:
2414:
2388:
2374:
2325:
2318:
2300:
2263:
2242:
2214:
2205:
2184:
2175:
2162:
2155:
2132:
2123:
2116:
2098:
2073:
2061:
2041:
2020:
1995:
1988:
1966:
1936:
1918:
1900:
1883:
1877:978-0567025920
1876:
1858:
1849:
1837:
1823:
1814:
1805:
1788:
1769:
1745:
1720:
1719:
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1565:
1562:
1516:
1513:
1492:
1489:
1456:Main article:
1445:
1442:
1429:
1428:Inclined plane
1426:
1424:
1421:
1412:
1409:
1407:
1404:
1386:
1383:
1316:
1313:
1311:
1308:
1236:
1233:
1200:
1197:
1157:
1154:
1120:
1117:
1054:Grindley Brook
1013:
1010:
978:
975:
914:
911:
909:
906:
889:
886:
861:
858:
855:Chenango Canal
851:Paw Paw Tunnel
845:
842:
826:
823:
818:Henry C. Flagg
787:
786:Snubbing posts
784:
766:
763:
750:
747:
738:
735:
710:
707:
706:
705:
697:Caversham Lock
695:
688:
686:
680:
673:
671:
665:
658:
656:
649:
642:
640:
625:
618:
616:
593:
586:
584:
577:
570:
566:
563:
546:
543:
528:
525:
512:Rochdale Canal
508:Tuel Lane Lock
500:Bath deep lock
491:
488:
486:
483:
458:
457:
454:
451:
448:
441:
440:
432:
425:
412:
411:
408:
405:
402:
398:
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380:
377:
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370:
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366:
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360:
356:
355:
352:
349:
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342:
341:
338:
331:
307:
304:
170:
167:
99:A gate in the
26:
9:
6:
4:
3:
2:
3136:
3125:
3122:
3120:
3117:
3115:
3112:
3110:
3107:
3105:
3102:
3100:
3097:
3095:
3092:
3091:
3089:
3080:
3077:
3074:
3071:
3069:
3067:
3061:
3058:
3056:
3053:
3052:
3041:
3035:
3031:
3026:
3025:
3003:
2999:
2992:
2983:
2975:
2973:0-7153-8555-0
2969:
2965:
2958:
2944:on 2013-08-10
2940:
2933:
2926:
2919:
2918:1-870002-59-8
2915:
2911:
2905:
2889:
2885:
2884:London Canals
2881:
2875:
2859:
2855:
2851:
2845:
2829:
2825:
2821:
2815:
2809:
2808:Robert Weldon
2804:
2790:on 2011-09-27
2789:
2785:
2779:
2773:
2772:0-00-713666-8
2769:
2765:
2760:
2752:
2748:
2744:
2737:
2721:
2717:
2711:
2702:
2693:
2684:
2675:
2667:
2663:
2659:
2655:
2651:
2647:
2643:
2639:
2638:
2633:
2627:
2612:
2608:
2601:
2586:
2582:
2576:
2562:on 2011-07-26
2561:
2557:
2551:
2536:
2530:
2515:
2508:
2493:
2487:
2472:
2468:
2462:
2447:
2443:
2437:
2431:
2430:0-7509-2077-7
2427:
2423:
2418:
2402:
2398:
2392:
2384:
2378:
2370:
2366:
2361:
2356:
2352:
2348:
2344:
2340:
2336:
2329:
2321:
2319:9781841584034
2315:
2311:
2304:
2285:
2281:
2274:
2267:
2260:
2256:
2252:
2246:
2231:
2224:
2218:
2209:
2202:
2198:
2194:
2188:
2179:
2172:
2166:
2158:
2156:0-8156-0139-5
2152:
2148:
2141:
2139:
2137:
2127:
2119:
2117:0-8156-0139-5
2113:
2109:
2102:
2087:
2083:
2077:
2070:
2065:
2058:
2054:
2053:
2045:
2030:
2024:
2009:
2005:
1999:
1991:
1989:0-948975-15-6
1985:
1980:
1979:
1970:
1954:
1950:
1946:
1945:"Second Lock"
1940:
1932:
1928:
1922:
1914:
1910:
1904:
1898:, p. 23.
1897:
1892:
1890:
1888:
1879:
1873:
1869:
1862:
1853:
1844:
1842:
1832:
1830:
1828:
1818:
1809:
1801:
1800:
1792:
1784:
1780:
1773:
1759:
1755:
1749:
1735:
1731:
1725:
1721:
1711:
1708:
1706:
1703:
1701:
1698:
1696:
1693:
1691:
1688:
1686:
1683:
1681:
1678:
1676:
1673:
1671:
1668:
1666:
1663:
1661:
1658:
1656:
1653:
1651:
1648:
1646:
1643:
1641:
1638:
1637:
1633:
1627:
1622:
1619:
1608:
1601:
1599:
1598:Milton Keynes
1595:
1591:
1587:
1583:
1574:
1570:
1564:Diagonal lock
1561:
1556:
1521:
1512:
1510:
1506:
1502:
1498:
1488:
1486:
1482:
1478:
1474:
1469:
1465:
1464:Robert Weldon
1459:
1450:
1441:
1439:
1435:
1420:
1418:
1403:
1401:
1397:
1393:
1382:
1380:
1376:
1372:
1368:
1363:
1361:
1357:
1353:
1349:
1345:
1338:
1334:
1329:
1321:
1307:
1305:
1301:
1297:
1293:
1289:
1285:
1280:
1276:
1272:
1268:
1264:
1257:
1253:
1249:
1241:
1232:
1230:
1225:
1221:
1216:
1209:
1205:
1196:
1194:
1190:
1186:
1181:
1179:
1178:HĂ©rault River
1175:
1174:Canal du Midi
1171:
1162:
1153:
1151:
1147:
1143:
1139:
1135:
1131:
1127:
1116:
1112:
1108:
1102:
1097:
1093:
1091:
1087:
1083:
1082:Watford Locks
1079:
1075:
1071:
1067:
1063:
1059:
1055:
1051:
1046:
1042:
1039:
1035:
1029:
1023:
1018:
1009:
1005:
1002:
1000:
992:
988:
983:
974:
972:
968:
963:
961:
957:
953:
949:
944:
940:
936:
932:
928:
919:
908:Special cases
905:
903:
899:
895:
885:
883:
879:
875:
871:
867:
857:
856:
852:
822:
819:
814:
792:
783:
779:
775:
772:
762:
755:
746:
744:
734:
732:
728:
724:
720:
716:
702:
698:
692:
687:
684:
677:
672:
669:
662:
657:
653:
646:
641:
637:
633:
629:
626:Top gates of
622:
617:
613:
609:
605:
601:
597:
590:
585:
581:
574:
569:
568:
565:Photo gallery
562:
560:
556:
552:
542:
540:
536:
535:
524:
521:
517:
513:
509:
505:
501:
497:
474:
470:
466:
462:
455:
452:
449:
446:
445:
444:
437:
433:
430:
426:
423:
420:A watertight
419:
418:
417:
399:
385:
371:
357:
343:
336:
328:
325:
317:
312:
303:
301:
296:
294:
290:
287:(part of the
286:
282:
278:
274:
270:
266:
261:
259:
253:
248:
246:
243:
239:
238:
233:
230:
226:
222:
218:
213:
211:
207:
203:
199:
195:
188:
184:
180:
175:
166:
164:
160:
155:
153:
149:
145:
141:
137:
133:
129:
125:
121:
114:
109:
102:
101:Hatton flight
97:
90:
86:
82:
78:
71:
67:
62:
55:
51:
46:
40:
33:
19:
3114:Song dynasty
3063:
3029:
3021:Bibliography
3006:. Retrieved
3002:the original
2991:
2982:
2963:
2957:
2946:. Retrieved
2939:the original
2925:
2909:
2904:
2894:25 September
2892:. Retrieved
2888:the original
2883:
2874:
2862:. Retrieved
2858:the original
2853:
2844:
2832:. Retrieved
2828:the original
2823:
2814:
2803:
2792:. Retrieved
2788:the original
2778:
2759:
2742:
2736:
2724:. Retrieved
2720:the original
2710:
2701:
2692:
2683:
2674:
2641:
2635:
2626:
2614:. Retrieved
2610:
2600:
2589:. Retrieved
2584:
2575:
2564:. Retrieved
2560:the original
2550:
2539:. Retrieved
2529:
2517:. Retrieved
2507:
2495:. Retrieved
2486:
2475:. Retrieved
2470:
2461:
2450:. Retrieved
2445:
2436:
2421:
2417:
2407:21 September
2405:. Retrieved
2400:
2391:
2385:(in German).
2377:
2342:
2338:
2328:
2309:
2303:
2291:. Retrieved
2284:the original
2266:
2250:
2245:
2235:21 September
2233:. Retrieved
2229:
2217:
2208:
2192:
2187:
2178:
2170:
2165:
2146:
2130:Unrau p. 336
2126:
2107:
2101:
2090:. Retrieved
2088:. 2018-05-17
2085:
2082:"Canal Lock"
2076:
2064:
2056:
2050:
2044:
2033:. Retrieved
2023:
2011:. Retrieved
2008:Google Books
2007:
1998:
1977:
1969:
1957:. Retrieved
1953:the original
1948:
1939:
1921:
1903:
1867:
1861:
1852:
1817:
1808:
1797:
1791:
1782:
1772:
1761:. Retrieved
1757:
1748:
1737:. Retrieved
1733:
1724:
1670:Control lock
1578:
1526:
1494:
1479:; 44.1
1461:
1458:Caisson lock
1444:Caisson lock
1431:
1423:Alternatives
1414:
1406:Use of water
1392:Garston Lock
1388:
1367:Song Dynasty
1364:
1341:
1300:Irtysh River
1298:Lock on the
1286:lock on the
1277:serving the
1261:In 2016 the
1260:
1217:
1213:
1193:River Allier
1182:
1167:
1122:
1113:
1109:
1105:
1078:Foxton Locks
1047:
1043:
1037:
1033:
1030:
1027:
1006:
1003:
995:
977:Lock flights
964:
952:Oxford Canal
939:Panama Canal
934:
930:
926:
924:
891:
888:Fish ladders
863:
847:
817:
815:
797:
780:
776:
770:
768:
760:
740:
726:
712:
612:sluice gates
600:Eynsham Lock
596:Upper Thames
558:
554:
550:
548:
538:
532:
530:
495:
493:
472:
463:
459:
442:
435:
428:
421:
415:
323:
297:
262:
255:
250:
244:
235:
217:Song Dynasty
214:
193:
191:
156:
140:caisson lock
119:
117:
91:river, China
18:Lock (water)
3068:for clarity
2345:: 291–302.
1959:4 September
1705:Water slope
1550: /
1509:Camden Lock
1360:canal locks
1288:River RhĂ´ne
1156:Round locks
1132:joined the
1090:Grand Union
962:, Germany.
902:fish ladder
866:ship canals
741:On the old
727:miter gates
608:Oxfordshire
520:Ardnacrusha
258:Grand Canal
221:Qiao Weiyue
3088:Categories
3008:6 November
2948:2015-09-06
2794:2011-08-05
2726:11 January
2591:2022-01-22
2566:2011-08-05
2541:2011-08-05
2519:23 October
2497:22 October
2477:2010-11-24
2452:2010-11-23
2201:0801853281
2092:2023-08-13
2035:2012-03-23
1763:2023-10-05
1739:2023-10-05
1716:References
1680:Hydraulics
1535:52°18′23″N
1515:Shaft lock
1475:(304
1371:West River
1352:Ptolemy II
1344:flash lock
1315:Pound lock
1304:Kazakhstan
1199:Drop locks
1119:Stop locks
948:Hillmorton
874:electrical
825:Variations
743:Erie Canal
628:Jesus Lock
559:miter sill
252:flow out.
210:flash lock
194:pound lock
169:Pound lock
146:, or on a
132:watercraft
130:and other
103:in England
83:lock near
72:in Germany
70:Heidelberg
39:Water gate
2864:6 October
2834:6 October
2751:0309-1422
2666:191374346
2261:pp. 71–72
2049:"Reach".
1710:Watermill
1538:8°55′11″E
1485:George IV
1398:, on the
1356:engineers
1210:drop lock
1191:with the
1126:Kidsgrove
1034:staircase
1024:, England
987:Caen Hill
870:hydraulic
654:, Austria
638:, England
636:Cambridge
632:River Cam
436:lock gear
434:A set of
265:Vreeswijk
183:Äänekoski
181:Canal at
144:boat lift
136:waterways
54:Marsworth
2616:30 March
2556:"Latest"
2369:55266451
2223:"p. 812"
2203:, p. 133
2195:. 1996.
1931:Archived
1913:Archived
1604:See also
1592:between
1466:for the
1337:Thatcham
1144:and the
935:twinning
927:doubling
882:capstans
245:Song Shi
232:Shen Kuo
229:polymath
225:slipways
179:Päijänne
2347:Bibcode
2293:May 24,
2230:nps.gov
1594:Bedford
1379:Jiangsu
1375:Huai'an
1296:Oskemen
1284:Bollène
1265:in the
1222:on the
1220:Dalmuir
1208:Dalmuir
1172:on the
1088:of the
1084:on the
1064:on the
1050:Bingley
1022:Bingley
999:Devizes
989:on the
960:MĂĽnster
950:on the
931:pairing
808:⁄
604:Eynsham
582:, Paris
510:on the
502:on the
422:chamber
379:11–12.
281:Italian
152:caisson
89:Yangtze
85:Yichang
3109:Rivers
3099:Canals
3036:
2970:
2916:
2770:
2749:
2664:
2658:500198
2656:
2428:
2401:ny.gov
2367:
2316:
2257:
2199:
2153:
2114:
2013:20 May
1986:
1874:
1695:Sluice
1586:Kendal
1434:Foxton
1394:, and
1350:under
1038:flight
937:. The
898:salmon
737:Paddle
709:Gates
439:pumps.
277:Bruges
202:rivers
198:canals
66:Neckar
2942:(PDF)
2935:(PDF)
2662:S2CID
2654:JSTOR
2365:S2CID
2287:(PDF)
2276:(PDF)
2226:(PDF)
1640:Canal
1373:near
1070:tides
958:near
933:, or
894:trout
771:swell
723:steel
683:canal
539:reach
534:pound
527:Pound
516:Douro
373:4–5.
351:8–9.
345:1–2.
316:gates
289:Milan
275:near
273:Damme
269:basin
206:gates
163:canal
159:river
128:ships
124:boats
3034:ISBN
3010:2016
2968:ISBN
2914:ISBN
2896:2013
2866:2006
2836:2006
2768:ISBN
2747:ISSN
2728:2011
2618:2022
2521:2007
2499:2007
2426:ISBN
2409:2018
2314:ISBN
2295:2013
2255:ISBN
2237:2018
2197:ISBN
2151:ISBN
2112:ISBN
2015:2013
1984:ISBN
1961:2006
1872:ISBN
1596:and
1229:burn
1080:and
1060:and
1052:and
1036:and
896:and
555:sill
551:cill
549:The
545:Cill
506:and
496:rise
494:The
490:Rise
429:gate
407:14.
393:13.
365:10.
200:and
142:, a
120:lock
32:Loch
2646:doi
2611:VRT
2355:doi
2343:102
1584:to
1481:psi
1477:kPa
1473:atm
1377:in
1302:in
872:or
719:elm
717:or
715:oak
634:in
598:at
541:).
401:7.
387:6.
359:3.
185:in
87:on
68:at
52:at
3090::
3062:–
2882:.
2852:.
2822:.
2745:.
2660:.
2652:.
2642:54
2640:.
2609:.
2583:.
2469:.
2444:.
2399:.
2363:.
2353:.
2341:.
2337:.
2278:.
2228:.
2135:^
2084:.
2006:.
1947:.
1886:^
1840:^
1826:^
1781:.
1756:.
1732:.
1600:.
1402:.
1362:.
1231:.
1195:.
1180:.
1092:.
1001:.
929:,
769:A
606:,
602:,
531:A
427:A
212:.
192:A
126:,
118:A
3042:.
3012:.
2976:.
2951:.
2920:.
2898:.
2868:.
2838:.
2797:.
2753:.
2730:.
2668:.
2648::
2620:.
2594:.
2569:.
2544:.
2523:.
2501:.
2480:.
2455:.
2411:.
2371:.
2357::
2349::
2322:.
2297:.
2239:.
2159:.
2120:.
2095:.
2038:.
2017:.
1992:.
1963:.
1880:.
1785:.
1766:.
1742:.
810:2
806:1
803:+
801:2
614:.
41:.
34:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.