680:
34:
578:
546:, 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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1370:. 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,
1317:
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66:
1601:
993:"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.
97:
85:
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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
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1104:"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.
1100:
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.
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734:, 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
1378:
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
1215:
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.
1335:, 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.
503:, 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
1429:. 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.
962:, 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
1500:, 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.
1358:(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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307:. 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.
2017:
291:: 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.
420:(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
873:, 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.
1517:
examples have been built at Saint Denis (Paris, France), Horin (near Melnik, Czech Republic) and Anderten (Hannover Germany). The shaft lock at Minden
893:
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.
750:
On the Chesapeake and Ohio Canal, the lockkeepers were required to remove the windlasses from all lock paddles at night, to prevent unauthorized use.
1901:
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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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958:, 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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2324:"Can navigation locks be used to help migratory fishes with poor swimming performance pass tidal barrages? A test with lampreys"
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1061:– the new bottom chamber rises just far enough to get the boat over the original lock cill. In China, the recently completed
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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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127:. 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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2596:""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
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1476:), but it had various engineering problems and the design was not put into use on the Coal Canal.
1408:, 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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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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1472:), in total. One of these "locks" was built and demonstrated to the Prince Regent (later
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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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943:. 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.
599:, England. Visible on the gates are the paddle winding gears, used to operate the
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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
857:, the gates and paddles are too large to be hand operated, and are operated by
208:(960–1279 CE), having been pioneered by the Song politician and naval engineer
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2926:. ICOMOS (the International Council on Monuments and Sites). Archived from
1719:"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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256:, Netherlands. This pound lock serviced many ships at once in a large
1993:"Final Report of the International Commission for the Study of Locks"
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2386:"Governor Cuomo Announces Funding For Restoration of Lockport Locks"
1791:. 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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2046:...the portion of a canal between two locks, having a uniform level
2044:(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
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1129:. 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
26:"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
2503:"Mitsubishi helps breath new life into important canal routes"
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2839:"History of the Caisson Lock On the Somersetshire Coal Canal"
1832:
1830:
1820:
1818:
1816:
252:
In medieval Europe a sort of pound lock was built in 1373 at
1880:
1878:
1876:
454:
boats to go through in convoy, and it also uses less water.
2297:
Cameron, A.D. (2005). "10 Working the canal in the 1820s".
853:
On large modern canals, especially very large ones such as
287:
In Ancient Egypt, the river-locks was probably part of the
249:
the level was raised in this way by 138 feet (42 m).
1354:
Pound locks were first used in medieval China during the
1283:
have a fall of 24.67 m (80.9 ft), each and the
788:
due to the friction of the rope against the post. A rope
567:
The cill exposed in the deep Pont de Flandre lock on the
216:
that had caused trouble and are mentioned by the Chinese
1496:
built one of these locks at the site of the present-day
2570:"Officiële opening van de grootste zeesluis ter wereld"
2138:. Syracuse, NY: Syracuse University Press. p. 39.
2099:. Syracuse, NY: Syracuse University Press. p. 38.
371:
The lock is emptied by draining its water downstream.
2623:(1950). "Three Canal Projects, Roman and Byzantine".
1451:
Around 1800 the use of caisson locks was proposed by
260:. Yet the first true pound lock was built in 1396 at
2269:
US Department of the Interior, National Park Service
2058:
Merriam-Webster Dictionary, definition of miter sill
1037:
Examples of famous "real" staircases in England are
436:
The entrance gates are opened and the boat moves in.
2869:"Congreve's Hydro-Pneumatic Canal Lift – A Humbug!"
2730:Smithett, Robin (April 2012). "A bit on the side".
1964:
838:Chesapeake and Ohio Canal with the locks near the
395:
389:
381:
375:
367:
361:
353:
347:
339:
333:
139:, it is the chamber itself (usually then called a
445:The exit gates are opened and the boat moves out.
2953:World Canals: Inland Navigation Past and Present
229:(published in 1088), and fully described in the
204:Pound locks were first used in China during the
3021:(8th ed.). Imray Laurie Norie and Wilson.
2129:
2127:
2125:
714:). The most common arrangement, usually called
583:The balance beams typical of many locks on the
2813:Bath Royal Literary and Scientific Institution
1768:"7 of the World's Most Impressive Canal Locks"
1425:in Leicestershire on the Leicester arm of the
1157:The best known example of a round lock is the
1088:Instructions for descent of treble staircase,
1009:Staircase of four locks, dating from 1774, at
16:Device for raising and lowering boats or ships
365:The lock is filled with water from upstream.
8:
2899:The Regent's Canal: London's Hidden Waterway
1484:Possibly inspired by Weldon's caisson lock,
1271:designed to operate under. For example, the
869:the lock gates were operated by man-powered
1884:
2773:"Foxton Inclined Plane Trust: Restoration"
2136:Canal Boatman My Life on Upstate Waterways
2097:Canal Boatman My Life on Upstate Waterways
111:is a device used for raising and lowering
2594:van den Buijs, Dennis (26 January 2022).
2347:
889:go upstream to spawn. Measures such as a
3049:Interactive simulation of lock operation
2921:"The International Canal Monuments List"
2705:"British Waterways 'Waterscape' website"
2755:, Volume 3, Harper Collins Publishers,
2020:. Irish Waterways History. 22 July 2009
1710:
1295:has a drop of 42 m (138 ft).
1045:. Two-rise staircases are more common:
722:sometime around the late 15th century.
557:
193:today. A pound lock has a chamber with
2843:The Somersetshire Coal Canal (Society)
313:Principle of operation of a pound lock
1117:, where the southern terminus of the
405:All pound locks have three elements:
212:in 984. They replaced earlier double
150:more easily navigable, or to allow a
7:
2955:. David & Charles. p. 162.
1922:from the original on 4 January 2022.
1801:Needham, Volume 4, Part 3, 350-351.
1577:and the proposed new branch of the
2301:(4 ed.). Edinburgh: Birlinn.
1810:Needham, Volume 4, Part 3, 351–52.
1324:on the Kennet & Avon Canal at
1137:was replaced in 1914 by a pair of
14:
3019:Inland Waterways of Great Britain
2547:. Waterways World. Archived from
2162:. Seven Locks Press, 1983. p. 207
1904:from the original on 2 June 2023.
1788:Science and Civilisation in China
1766:Newcomb, Tim (13 December 2016).
1613:
1599:
902:Doubled, paired or twinned locks
678:
663:
648:
639:200-year-old paddle gear on the
632:
608:
576:
560:
322:
295:Basic construction and operation
2626:American Journal of Archaeology
1859:. Bloomsbury 3PL. p. 236.
1845:Needham, Volume 4, Part 3, 358.
1836:Needham, Volume 4, Part 3, 357.
1824:Needham, Volume 4, Part 3, 351.
655:Water conservation gear on the
3113:Water transport infrastructure
3044:Deepest Canal Locks in England
1135:Worcester and Birmingham Canal
439:The entrance gates are closed.
1:
2775:. Fipt.org.uk. Archived from
2501:voltimum (11 December 2002).
2349:10.1016/J.ECOLENG.2017.02.027
2018:"The ESB lock at Ardnacrusha"
1512:Entrance to Minden shaft lock
1331:The natural extension of the
954:The once-famous staircase at
465:1–3. Boat enters 'empty' lock
329:For a boat going downstream:
2271:. p. 15. Archived from
1855:Gmirkin, Russell E. (2006).
1654:Canals of the United Kingdom
657:Birmingham Canal Navigations
385:The lower gates are opened.
379:The upper gates are opened.
357:The upper gates are closed.
351:The lower gates are closed.
166:A pound lock on the Keitele–
2667:Rappoport 1904, pp. 250-253
2372:"Zwillingsschleuse MĂĽnster"
2242:. Seven Locks Press, 1983,
1967:The Kennet & Avon Canal
319:For a boat going upstream:
3129:
3017:Cumberlidge, Jane (2009).
2987:"Diagonal Lock – Overview"
2951:Hadfield, Charles (1986).
2456:"Canal lateral a la Loire"
2060:, Retrieved Jan. 28, 2015.
1898:"How do canal locks work?"
1743:"Different types of locks"
1480:Hydro-pneumatic canal lift
1444:
974:The flight of 16 locks at
398:
392:
384:
378:
370:
364:
356:
350:
343:The boat enters the lock.
342:
337:The boat enters the lock.
336:
280:canal system sponsored by
25:
18:
3053:this demonstration shows
2809:"The Somerset Coal Canal"
2753:Nicholson Waterways Guide
2413:, Ray Shill, 1999, 2002,
2260:Bearss, Edwin C. (1968).
2134:Garrity, Richard (1977).
2095:Garrity, Richard (1977).
2041:Oxford English Dictionary
1971:. Bath: Millstream Book.
1674:List of canals by country
1441:Operation of caisson lock
1131:Stratford-upon-Avon Canal
462:Operation of a canal lock
399:The boat exits the lock.
393:The boat exits the lock.
328:
321:
318:
284:) between 1452 and 1458.
185:is most commonly used on
146:Locks are used to make a
45:in Hertfordshire, England
3083:Locks (water navigation)
2694:Schörner 2000, pp. 33–35
1178:Canal latéral à la Loire
710:but now usually made of
670:Lock gate controls on a
550:(mitre sill in Canada).
223:(1031–1095) in his book
143:) that rises and falls.
19:Not to be confused with
2985:Fogarty, Terry (2008).
2919:Hughes, Stephen (ed.).
2901:. Waterways World Ltd.
2897:Faulkner, Alan (2005):
2201:Garrity, Richard. p. 41
2171:Garrity, Richard. p. 40
1916:"Staircase Canal Locks"
1644:Canal & River Trust
1299:History and development
1281:Rhine–Main–Danube Canal
1241:Upper Mississippi River
641:Wiener Neustädter Kanal
474:Details and terminology
231:Chinese historical text
2975:Hadfield (1986) p. 55.
2676:Moore 1950, pp. 99–101
2328:Ecological Engineering
1963:Allsop, Niall (1987).
1747:canalrivertrust.org.uk
1565:
1513:
1442:
1343:(284 to 246 BC), when
1328:
1313:
1247:
1233:
1200:
1154:
1127:Trent and Mersey Canal
1092:
1014:
982:
911:
829:
784:
747:
470:
308:
274:Naviglio di Bereguardo
243:
178:
104:
93:
81:
62:
46:
3062:Interactive lock game
3055:guillotine-type gates
2524:"Clydebank Drop Lock"
2262:"The Composite Locks"
1664:Hydraulic engineering
1607:United Kingdom portal
1560:
1511:
1494:Regents Canal Company
1440:
1389:Kennet and Avon Canal
1337:Canal of the Pharaohs
1319:
1311:
1239:
1231:
1213:Forth and Clyde Canal
1195:
1152:
1087:
1008:
980:Kennet and Avon Canal
973:
909:
827:
782:
767:money for the swell.
745:
738:Windlass ("lock key")
619:, a beam lock on the
493:Kennet and Avon Canal
460:
302:
289:Canal of the Pharaohs
238:
165:
102:Saint Lawrence Seaway
100:Iroquois Lock on the
99:
87:
68:
52:
36:
2879:on 27 September 2013
2621:Moore, Frank Gardner
2299:The Caledonian Canal
1918:. Droitwich Canals.
1536:52.30639°N 8.91972°E
1174:Écluse des Lorraines
1055:Driffield Navigation
1051:Struncheon Hill Lock
690:hydraulic mechanisms
236:(compiled in 1345):
137:canal inclined plane
2993:on 15 February 2017
2819:on 14 November 2006
2685:Froriep 1986, p. 46
2481:"Dalmuir Drop Lock"
2411:Birmingham's Canals
2340:2017EcEng.102..291S
1944:on 16 November 2007
1649:Canals of Amsterdam
1639:Channel (geography)
1532: /
1457:Somerset Coal Canal
1400:Water saving basins
315:
3093:Chinese inventions
2849:on 11 October 2006
2633:(2): 97–111 (99).
2462:. grehanman guides
2437:. grehanman guides
2238:Kytle, Elizabeth.
2180:Kytle, Elizabeth.
2158:Kytle, Elizabeth.
1723:www.britannica.com
1634:Canal Safety Gates
1566:
1514:
1490:pneumatic caissons
1443:
1329:
1314:
1248:
1245:Lock and Dam No. 6
1234:
1201:
1155:
1119:Macclesfield Canal
1093:
1090:Chesterfield Canal
1015:
983:
960:Niagara Escarpment
956:Lockport, New York
945:Dortmund–Ems Canal
912:
865:equipment. On the
830:
785:
748:
718:, was invented by
471:
311:
309:
179:
105:
94:
82:
63:
53:Lock on the River
47:
3028:978-1-84623-010-3
2576:. 26 January 2022
2574:Port of Amsterdam
2248:978-0-932020-13-0
2240:Home on the Canal
2182:Home on the Canal
2160:Home on the Canal
1938:Images of England
1900:. ABC Boat Hire.
1772:Popular Mechanics
1679:List of waterways
1579:Grand Union Canal
1541:52.30639; 8.91972
1427:Grand Union Canal
1385:Monkey Marsh Lock
1322:Monkey Marsh Lock
1268:Port of Amsterdam
1264:IJmuiden sea lock
1176:, connecting the
1123:Hall Green Branch
849:Powered operation
825:
754:Swell or swelling
720:Leonardo da Vinci
569:Canal Saint-Denis
403:
402:
226:Dream Pool Essays
39:Grand Union Canal
3120:
3032:
3003:
3002:
3000:
2998:
2989:. Archived from
2982:
2976:
2973:
2967:
2966:
2948:
2942:
2941:
2939:
2938:
2932:
2925:
2916:
2910:
2895:
2889:
2888:
2886:
2884:
2875:. Archived from
2865:
2859:
2858:
2856:
2854:
2845:. Archived from
2835:
2829:
2828:
2826:
2824:
2815:. Archived from
2805:
2799:
2794:
2788:
2787:
2785:
2784:
2769:
2763:
2750:
2744:
2743:
2727:
2721:
2720:
2718:
2716:
2707:. Archived from
2701:
2695:
2692:
2686:
2683:
2677:
2674:
2668:
2665:
2659:
2658:
2617:
2611:
2610:
2608:
2606:
2591:
2585:
2584:
2582:
2581:
2566:
2560:
2559:
2557:
2556:
2541:
2535:
2534:
2532:
2531:
2520:
2514:
2513:
2511:
2509:
2498:
2492:
2491:
2489:
2487:
2477:
2471:
2470:
2468:
2467:
2460:Afloat in France
2452:
2446:
2445:
2443:
2442:
2435:Afloat in France
2427:
2421:
2408:
2402:
2401:
2399:
2397:
2392:. 17 August 2015
2382:
2376:
2375:
2368:
2362:
2361:
2351:
2319:
2313:
2312:
2294:
2288:
2287:
2285:
2283:
2277:
2266:
2257:
2251:
2236:
2230:
2229:
2227:
2225:
2216:
2208:
2202:
2199:
2193:
2178:
2172:
2169:
2163:
2156:
2150:
2149:
2131:
2120:
2117:
2111:
2110:
2092:
2086:
2085:
2083:
2082:
2075:Encyclopedia.com
2067:
2061:
2055:
2049:
2048:
2035:
2029:
2028:
2026:
2025:
2014:
2008:
2007:
2005:
2003:
1989:
1983:
1982:
1970:
1960:
1954:
1953:
1951:
1949:
1940:. Archived from
1930:
1924:
1923:
1912:
1906:
1905:
1894:
1888:
1885:Cumberlidge 2009
1882:
1871:
1870:
1852:
1846:
1843:
1837:
1834:
1825:
1822:
1811:
1808:
1802:
1799:
1793:
1792:
1782:
1776:
1775:
1763:
1757:
1756:
1754:
1753:
1739:
1733:
1732:
1730:
1729:
1715:
1623:
1621:Transport portal
1618:
1617:
1609:
1604:
1603:
1602:
1562:Three Gorges Dam
1547:
1546:
1544:
1543:
1542:
1537:
1533:
1530:
1529:
1528:
1525:
1486:William Congreve
1260:Berendrecht Lock
1224:Very large locks
1075:Leicester Branch
1063:Three Gorges Dam
1001:Staircase locks
867:Caledonian Canal
826:
801:
800:
796:
793:
682:
667:
652:
636:
612:
580:
564:
326:
316:
310:
282:Francesco Sforza
70:Three Gorges Dam
3128:
3127:
3123:
3122:
3121:
3119:
3118:
3117:
3073:
3072:
3040:
3035:
3029:
3016:
3012:
3007:
3006:
2996:
2994:
2984:
2983:
2979:
2974:
2970:
2963:
2950:
2949:
2945:
2936:
2934:
2930:
2923:
2918:
2917:
2913:
2896:
2892:
2882:
2880:
2867:
2866:
2862:
2852:
2850:
2837:
2836:
2832:
2822:
2820:
2807:
2806:
2802:
2795:
2791:
2782:
2780:
2771:
2770:
2766:
2751:
2747:
2732:Waterways World
2729:
2728:
2724:
2714:
2712:
2711:on 3 April 2012
2703:
2702:
2698:
2693:
2689:
2684:
2680:
2675:
2671:
2666:
2662:
2619:
2618:
2614:
2604:
2602:
2593:
2592:
2588:
2579:
2577:
2568:
2567:
2563:
2554:
2552:
2543:
2542:
2538:
2529:
2527:
2522:
2521:
2517:
2507:
2505:
2500:
2499:
2495:
2485:
2483:
2479:
2478:
2474:
2465:
2463:
2454:
2453:
2449:
2440:
2438:
2431:"Canal du Midi"
2429:
2428:
2424:
2409:
2405:
2395:
2393:
2384:
2383:
2379:
2370:
2369:
2365:
2321:
2320:
2316:
2309:
2296:
2295:
2291:
2281:
2279:
2278:on July 3, 2007
2275:
2264:
2259:
2258:
2254:
2237:
2233:
2223:
2221:
2214:
2210:
2209:
2205:
2200:
2196:
2179:
2175:
2170:
2166:
2157:
2153:
2146:
2133:
2132:
2123:
2118:
2114:
2107:
2094:
2093:
2089:
2080:
2078:
2069:
2068:
2064:
2056:
2052:
2037:
2036:
2032:
2023:
2021:
2016:
2015:
2011:
2001:
1999:
1991:
1990:
1986:
1979:
1962:
1961:
1957:
1947:
1945:
1932:
1931:
1927:
1914:
1913:
1909:
1896:
1895:
1891:
1883:
1874:
1867:
1854:
1853:
1849:
1844:
1840:
1835:
1828:
1823:
1814:
1809:
1805:
1800:
1796:
1784:
1783:
1779:
1765:
1764:
1760:
1751:
1749:
1741:
1740:
1736:
1727:
1725:
1717:
1716:
1712:
1707:
1689:Water resources
1619:
1612:
1605:
1600:
1598:
1595:
1571:Lancaster Canal
1555:
1540:
1538:
1534:
1531:
1526:
1523:
1521:
1519:
1518:
1506:
1482:
1449:
1435:
1419:
1414:
1406:Droitwich Canal
1402:
1397:
1376:
1374:Turf-sided lock
1320:The turf-sided
1306:
1301:
1256:Port of Antwerp
1252:Kieldrecht Lock
1243:
1226:
1190:
1159:Agde Round Lock
1153:Agde Round Lock
1147:
1139:guillotine lock
1125:of the earlier
1110:
1047:Snakeholme Lock
1003:
968:
932:SBE Engineering
904:
899:
879:
851:
842:. and also the
835:
833:Composite locks
818:
816:
798:
794:
791:
789:
777:
756:
740:
728:
700:
693:
683:
674:
668:
659:
653:
644:
637:
628:
613:
604:
581:
572:
565:
556:
542:, also spelled
536:
518:
481:
476:
468:
466:
464:
297:
268:, Belgium. The
176:Central Finland
160:
31:
24:
17:
12:
11:
5:
3126:
3124:
3116:
3115:
3110:
3108:Types of gates
3105:
3100:
3095:
3090:
3085:
3075:
3074:
3071:
3070:
3065:
3059:
3046:
3039:
3038:External links
3036:
3034:
3033:
3027:
3013:
3011:
3008:
3005:
3004:
2977:
2968:
2961:
2943:
2911:
2890:
2860:
2830:
2800:
2789:
2764:
2745:
2722:
2696:
2687:
2678:
2669:
2660:
2639:10.2307/500198
2612:
2586:
2561:
2536:
2526:. Gentles.info
2515:
2493:
2472:
2447:
2422:
2403:
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2289:
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2105:
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2062:
2050:
2030:
2009:
1984:
1977:
1955:
1925:
1907:
1889:
1872:
1866:978-0567025920
1865:
1847:
1838:
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1812:
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1445:Main article:
1434:
1431:
1418:
1417:Inclined plane
1415:
1413:
1410:
1401:
1398:
1396:
1393:
1375:
1372:
1305:
1302:
1300:
1297:
1225:
1222:
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1186:
1146:
1143:
1109:
1106:
1043:Grindley Brook
1002:
999:
967:
964:
903:
900:
898:
895:
878:
875:
850:
847:
844:Chenango Canal
840:Paw Paw Tunnel
834:
831:
815:
812:
807:Henry C. Flagg
776:
775:Snubbing posts
773:
755:
752:
739:
736:
727:
724:
699:
696:
695:
694:
686:Caversham Lock
684:
677:
675:
669:
662:
660:
654:
647:
645:
638:
631:
629:
614:
607:
605:
582:
575:
573:
566:
559:
555:
552:
535:
532:
517:
514:
501:Rochdale Canal
497:Tuel Lane Lock
489:Bath deep lock
480:
477:
475:
472:
447:
446:
443:
440:
437:
430:
429:
421:
414:
401:
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397:
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344:
341:
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331:
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320:
296:
293:
159:
156:
88:A gate in the
15:
13:
10:
9:
6:
4:
3:
2:
3125:
3114:
3111:
3109:
3106:
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3015:
3014:
3009:
2992:
2988:
2981:
2978:
2972:
2969:
2964:
2962:0-7153-8555-0
2958:
2954:
2947:
2944:
2933:on 2013-08-10
2929:
2922:
2915:
2912:
2908:
2907:1-870002-59-8
2904:
2900:
2894:
2891:
2878:
2874:
2873:London Canals
2870:
2864:
2861:
2848:
2844:
2840:
2834:
2831:
2818:
2814:
2810:
2804:
2801:
2798:
2797:Robert Weldon
2793:
2790:
2779:on 2011-09-27
2778:
2774:
2768:
2765:
2762:
2761:0-00-713666-8
2758:
2754:
2749:
2746:
2741:
2737:
2733:
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2710:
2706:
2700:
2697:
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2644:
2640:
2636:
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2628:
2627:
2622:
2616:
2613:
2601:
2597:
2590:
2587:
2575:
2571:
2565:
2562:
2551:on 2011-07-26
2550:
2546:
2540:
2537:
2525:
2519:
2516:
2504:
2497:
2494:
2482:
2476:
2473:
2461:
2457:
2451:
2448:
2436:
2432:
2426:
2423:
2420:
2419:0-7509-2077-7
2416:
2412:
2407:
2404:
2391:
2387:
2381:
2378:
2373:
2367:
2364:
2359:
2355:
2350:
2345:
2341:
2337:
2333:
2329:
2325:
2318:
2315:
2310:
2308:9781841584034
2304:
2300:
2293:
2290:
2274:
2270:
2263:
2256:
2253:
2249:
2245:
2241:
2235:
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2220:
2213:
2207:
2204:
2198:
2195:
2191:
2187:
2183:
2177:
2174:
2168:
2165:
2161:
2155:
2152:
2147:
2145:0-8156-0139-5
2141:
2137:
2130:
2128:
2126:
2122:
2116:
2113:
2108:
2106:0-8156-0139-5
2102:
2098:
2091:
2088:
2076:
2072:
2066:
2063:
2059:
2054:
2051:
2047:
2043:
2042:
2034:
2031:
2019:
2013:
2010:
1998:
1994:
1988:
1985:
1980:
1978:0-948975-15-6
1974:
1969:
1968:
1959:
1956:
1943:
1939:
1935:
1934:"Second Lock"
1929:
1926:
1921:
1917:
1911:
1908:
1903:
1899:
1893:
1890:
1887:, p. 23.
1886:
1881:
1879:
1877:
1873:
1868:
1862:
1858:
1851:
1848:
1842:
1839:
1833:
1831:
1827:
1821:
1819:
1817:
1813:
1807:
1804:
1798:
1795:
1790:
1789:
1781:
1778:
1773:
1769:
1762:
1759:
1748:
1744:
1738:
1735:
1724:
1720:
1714:
1711:
1704:
1700:
1697:
1695:
1692:
1690:
1687:
1685:
1682:
1680:
1677:
1675:
1672:
1670:
1667:
1665:
1662:
1660:
1657:
1655:
1652:
1650:
1647:
1645:
1642:
1640:
1637:
1635:
1632:
1630:
1627:
1626:
1622:
1616:
1611:
1608:
1597:
1592:
1590:
1588:
1587:Milton Keynes
1584:
1580:
1576:
1572:
1563:
1559:
1553:Diagonal lock
1552:
1550:
1545:
1510:
1503:
1501:
1499:
1495:
1491:
1487:
1479:
1477:
1475:
1471:
1467:
1463:
1458:
1454:
1453:Robert Weldon
1448:
1439:
1432:
1430:
1428:
1424:
1416:
1411:
1409:
1407:
1399:
1394:
1392:
1390:
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1371:
1369:
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1357:
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1342:
1338:
1334:
1327:
1323:
1318:
1310:
1303:
1298:
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1278:
1274:
1269:
1265:
1261:
1257:
1253:
1246:
1242:
1238:
1230:
1223:
1221:
1219:
1214:
1210:
1205:
1198:
1194:
1187:
1185:
1183:
1179:
1175:
1170:
1168:
1167:HĂ©rault River
1164:
1163:Canal du Midi
1160:
1151:
1144:
1142:
1140:
1136:
1132:
1128:
1124:
1120:
1116:
1107:
1105:
1101:
1097:
1091:
1086:
1082:
1080:
1076:
1072:
1071:Watford Locks
1068:
1064:
1060:
1056:
1052:
1048:
1044:
1040:
1035:
1031:
1028:
1024:
1018:
1012:
1007:
1000:
998:
994:
991:
989:
981:
977:
972:
965:
963:
961:
957:
952:
950:
946:
942:
938:
933:
929:
925:
921:
917:
908:
901:
897:Special cases
896:
894:
892:
888:
884:
876:
874:
872:
868:
864:
860:
856:
848:
846:
845:
841:
832:
813:
811:
808:
803:
781:
774:
772:
768:
764:
761:
753:
751:
744:
737:
735:
733:
725:
723:
721:
717:
713:
709:
705:
697:
691:
687:
681:
676:
673:
666:
661:
658:
651:
646:
642:
635:
630:
626:
622:
618:
615:Top gates of
611:
606:
602:
598:
594:
590:
586:
579:
574:
570:
563:
558:
554:Photo gallery
553:
551:
549:
545:
541:
533:
531:
529:
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513:
510:
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502:
498:
494:
490:
486:
478:
473:
463:
459:
455:
451:
444:
441:
438:
435:
434:
433:
426:
422:
419:
415:
412:
409:A watertight
408:
407:
406:
388:
374:
360:
346:
332:
325:
317:
314:
306:
301:
294:
292:
290:
285:
283:
279:
276:(part of the
275:
271:
267:
263:
259:
255:
250:
248:
242:
237:
235:
232:
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222:
219:
215:
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207:
202:
200:
196:
192:
188:
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177:
173:
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157:
155:
153:
149:
144:
142:
138:
134:
130:
126:
122:
118:
114:
110:
103:
98:
91:
90:Hatton flight
86:
79:
75:
71:
67:
60:
56:
51:
44:
40:
35:
29:
22:
3103:Song dynasty
3052:
3018:
3010:Bibliography
2995:. Retrieved
2991:the original
2980:
2971:
2952:
2946:
2935:. Retrieved
2928:the original
2914:
2898:
2893:
2883:25 September
2881:. Retrieved
2877:the original
2872:
2863:
2851:. Retrieved
2847:the original
2842:
2833:
2821:. Retrieved
2817:the original
2812:
2803:
2792:
2781:. Retrieved
2777:the original
2767:
2748:
2731:
2725:
2713:. Retrieved
2709:the original
2699:
2690:
2681:
2672:
2663:
2630:
2624:
2615:
2603:. Retrieved
2599:
2589:
2578:. Retrieved
2573:
2564:
2553:. Retrieved
2549:the original
2539:
2528:. Retrieved
2518:
2506:. Retrieved
2496:
2484:. Retrieved
2475:
2464:. Retrieved
2459:
2450:
2439:. Retrieved
2434:
2425:
2410:
2406:
2396:21 September
2394:. Retrieved
2389:
2380:
2374:(in German).
2366:
2331:
2327:
2317:
2298:
2292:
2280:. Retrieved
2273:the original
2255:
2239:
2234:
2224:21 September
2222:. Retrieved
2218:
2206:
2197:
2181:
2176:
2167:
2159:
2154:
2135:
2119:Unrau p. 336
2115:
2096:
2090:
2079:. Retrieved
2077:. 2018-05-17
2074:
2071:"Canal Lock"
2065:
2053:
2045:
2039:
2033:
2022:. Retrieved
2012:
2000:. Retrieved
1997:Google Books
1996:
1987:
1966:
1958:
1946:. Retrieved
1942:the original
1937:
1928:
1910:
1892:
1856:
1850:
1841:
1806:
1797:
1786:
1780:
1771:
1761:
1750:. Retrieved
1746:
1737:
1726:. Retrieved
1722:
1713:
1659:Control lock
1567:
1515:
1483:
1468:; 44.1
1450:
1447:Caisson lock
1433:Caisson lock
1420:
1412:Alternatives
1403:
1395:Use of water
1381:Garston Lock
1377:
1356:Song Dynasty
1353:
1330:
1289:Irtysh River
1287:Lock on the
1275:lock on the
1266:serving the
1250:In 2016 the
1249:
1206:
1202:
1182:River Allier
1171:
1156:
1111:
1102:
1098:
1094:
1067:Foxton Locks
1036:
1032:
1026:
1022:
1019:
1016:
995:
992:
984:
966:Lock flights
953:
941:Oxford Canal
928:Panama Canal
923:
919:
915:
913:
880:
877:Fish ladders
852:
836:
806:
804:
786:
769:
765:
759:
757:
749:
729:
715:
701:
601:sluice gates
589:Eynsham Lock
585:Upper Thames
547:
543:
539:
537:
527:
521:
519:
484:
482:
461:
452:
448:
431:
424:
417:
410:
404:
312:
286:
251:
244:
239:
233:
224:
206:Song Dynasty
203:
182:
180:
145:
129:caisson lock
108:
106:
80:river, China
3057:for clarity
2334:: 291–302.
1948:4 September
1694:Water slope
1539: /
1498:Camden Lock
1349:canal locks
1277:River RhĂ´ne
1145:Round locks
1121:joined the
1079:Grand Union
951:, Germany.
891:fish ladder
855:ship canals
730:On the old
716:miter gates
597:Oxfordshire
509:Ardnacrusha
247:Grand Canal
210:Qiao Weiyue
3077:Categories
2997:6 November
2937:2015-09-06
2783:2011-08-05
2715:11 January
2580:2022-01-22
2555:2011-08-05
2530:2011-08-05
2508:23 October
2486:22 October
2466:2010-11-24
2441:2010-11-23
2190:0801853281
2081:2023-08-13
2024:2012-03-23
1752:2023-10-05
1728:2023-10-05
1705:References
1669:Hydraulics
1524:52°18′23″N
1504:Shaft lock
1464:(304
1360:West River
1341:Ptolemy II
1333:flash lock
1304:Pound lock
1293:Kazakhstan
1188:Drop locks
1108:Stop locks
937:Hillmorton
863:electrical
814:Variations
732:Erie Canal
617:Jesus Lock
548:miter sill
241:flow out.
199:flash lock
183:pound lock
158:Pound lock
135:, or on a
121:watercraft
119:and other
92:in England
72:lock near
61:in Germany
59:Heidelberg
28:Water gate
2853:6 October
2823:6 October
2740:0309-1422
2655:191374346
2250:pp. 71–72
2038:"Reach".
1699:Watermill
1527:8°55′11″E
1474:George IV
1387:, on the
1345:engineers
1199:drop lock
1180:with the
1115:Kidsgrove
1023:staircase
1013:, England
976:Caen Hill
859:hydraulic
643:, Austria
627:, England
625:Cambridge
621:River Cam
425:lock gear
423:A set of
254:Vreeswijk
172:Äänekoski
170:Canal at
133:boat lift
125:waterways
43:Marsworth
2605:30 March
2545:"Latest"
2358:55266451
2212:"p. 812"
2192:, p. 133
2184:. 1996.
1920:Archived
1902:Archived
1593:See also
1581:between
1455:for the
1326:Thatcham
1133:and the
924:twinning
916:doubling
871:capstans
234:Song Shi
221:Shen Kuo
218:polymath
214:slipways
168:Päijänne
2336:Bibcode
2282:May 24,
2219:nps.gov
1583:Bedford
1368:Jiangsu
1364:Huai'an
1285:Oskemen
1273:Bollène
1254:in the
1211:on the
1209:Dalmuir
1197:Dalmuir
1161:on the
1077:of the
1073:on the
1053:on the
1039:Bingley
1011:Bingley
988:Devizes
978:on the
949:MĂĽnster
939:on the
920:pairing
797:⁄
593:Eynsham
571:, Paris
499:on the
491:on the
411:chamber
368:11–12.
270:Italian
141:caisson
78:Yangtze
74:Yichang
3098:Rivers
3088:Canals
3025:
2959:
2905:
2759:
2738:
2653:
2647:500198
2645:
2417:
2390:ny.gov
2356:
2305:
2246:
2188:
2142:
2103:
2002:20 May
1975:
1863:
1684:Sluice
1575:Kendal
1423:Foxton
1383:, and
1339:under
1027:flight
926:. The
887:salmon
726:Paddle
698:Gates
428:pumps.
266:Bruges
191:rivers
187:canals
55:Neckar
2931:(PDF)
2924:(PDF)
2651:S2CID
2643:JSTOR
2354:S2CID
2276:(PDF)
2265:(PDF)
2215:(PDF)
1629:Canal
1362:near
1059:tides
947:near
922:, or
883:trout
760:swell
712:steel
672:canal
528:reach
523:pound
516:Pound
505:Douro
362:4–5.
340:8–9.
334:1–2.
305:gates
278:Milan
264:near
262:Damme
258:basin
195:gates
152:canal
148:river
117:ships
113:boats
3023:ISBN
2999:2016
2957:ISBN
2903:ISBN
2885:2013
2855:2006
2825:2006
2757:ISBN
2736:ISSN
2717:2011
2607:2022
2510:2007
2488:2007
2415:ISBN
2398:2018
2303:ISBN
2284:2013
2244:ISBN
2226:2018
2186:ISBN
2140:ISBN
2101:ISBN
2004:2013
1973:ISBN
1950:2006
1861:ISBN
1585:and
1218:burn
1069:and
1049:and
1041:and
1025:and
885:and
544:sill
540:cill
538:The
534:Cill
495:and
485:rise
483:The
479:Rise
418:gate
396:14.
382:13.
354:10.
189:and
131:, a
109:lock
21:Loch
2635:doi
2600:VRT
2344:doi
2332:102
1573:to
1470:psi
1466:kPa
1462:atm
1366:in
1291:in
861:or
708:elm
706:or
704:oak
623:in
587:at
530:).
390:7.
376:6.
348:3.
174:in
76:on
57:at
41:at
3079::
3051:–
2871:.
2841:.
2811:.
2734:.
2649:.
2641:.
2631:54
2629:.
2598:.
2572:.
2458:.
2433:.
2388:.
2352:.
2342:.
2330:.
2326:.
2267:.
2217:.
2124:^
2073:.
1995:.
1936:.
1875:^
1829:^
1815:^
1770:.
1745:.
1721:.
1589:.
1391:.
1351:.
1220:.
1184:.
1169:.
1081:.
990:.
918:,
758:A
595:,
591:,
520:A
416:A
201:.
181:A
115:,
107:A
3031:.
3001:.
2965:.
2940:.
2909:.
2887:.
2857:.
2827:.
2786:.
2742:.
2719:.
2657:.
2637::
2609:.
2583:.
2558:.
2533:.
2512:.
2490:.
2469:.
2444:.
2400:.
2360:.
2346::
2338::
2311:.
2286:.
2228:.
2148:.
2109:.
2084:.
2027:.
2006:.
1981:.
1952:.
1869:.
1774:.
1755:.
1731:.
799:2
795:1
792:+
790:2
603:.
30:.
23:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
