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35-585: The development of docks on both sides of the river around the Isle of Dogs indicated that a river crossing of some kind was needed. A tunnel from Rotherhithe to Limehouse was suggested in about 1803 in which the Nothumbrian engineer Robert Vazie became involved. An Act of Parliament was obtained on 12 July 1805 which enabled the Thames Archway Company to start construction. The idea

70-461: A bi-directional system since the year 2000 permitting boats to transfer between the tidal Bow Creek and Limehouse Cut. Bow Locks permits transfer near top of tide whether it be neap or spring. Generally inbounds enter on the rise and outbounds on the fall. In practical use, the operation of Bow Locks is tightly controlled by the duty lock-keeper as every tide is different. William Jessop William Jessop (23 January 1745 – 18 November 1814)

105-625: A form of paralysis, and 1805 marked the end of his active career. He died at his home, Butterley Hall , on 18 November 1814. His son Josias became a successful engineer in his own right. Jessop was in the unusual position of bridging the gap between the canal engineers and the railway engineers who came later. His name did not gain the lasting fame that it deserved because of his modesty. Indeed some of his works have been wrongly attributed to engineers who acted as his assistants. Unlike some engineers, such as George Stephenson , Jessop did not stoop to undignified wrangles with fellow professionals. He

140-434: A large tidal range. The tide must rise sufficiently to give them a clear passage over the raised sill. In 1775 Hull's Old Dock was opened. This was the first commercial floating dock, isolated by a lock rather than a single lock gate. This allowed the dock's water level to be maintained and, more importantly, it increased the time for which tidal access was possible. However the lock was only 121 ft long and this limited

175-623: A number of years before beginning to work as an engineer in his own right. He assisted Smeaton with the Calder and Hebble and the Aire and Calder navigations in Yorkshire. The first major work that Jessop is known to have carried out was the Grand Canal of Ireland . This had begun as a Government project in 1753, and it had taken seventeen years to build fourteen miles (21 km) of canal from

210-619: A pilot. Floating docks are generally maintained at a level at least as high as the highest tide. Apart from any considerations of navigation, lock gates are usually arranged as a chevron. and can only hold back higher water in one direction, which must always be from within the dock. A small but significant example of this is the locking system on the River Darent in Dartford, now in restoration and which were fully operational between 1899 and 1983. Maintaining this higher level requires

245-541: A shaft 12.8 metres (42 ft) deep and money was running out. In 1807 the directors of the company brought in Richard Trevithick who agreed to take the driftway across the river for a success fee of £1,000. Employing Cornish miners to dig and a 30-horsepower steam engine to pump, he eventually succeeded in making the driftway 313 metres (1,027 ft) from the Rotherhithe shaft: he had tunnelled under

280-461: A single lock gate isolating them from the tidal water. The gates were opened during the last hour [or two] of the rising tide, giving a short window of opportunity to let ships in on the rise and releasing outgoing ships while the tide was on the turn. The gates were closed at top of tide to maintain levels within the dock. Although this short opening period may have seemed disruptive, any attempt at longer opening might allow dock water-level to fall with

315-607: A supply of water. In some cases this is available from a river flowing into the harbour. This was the case for Bristol, at least initially, with the River Frome . Where there was no such river source, a mechanical pumping, or impounding , station was constructed. Liverpool's northern docks were served by one at Huskisson Dock and one on the opposite side of the Mersey for Wallasey Dock . Bow Locks in East London has used

350-461: Is impracticable". About 40 years later Marc Isambard Brunel and Isambard Kingdom Brunel built the Thames Tunnel about half a mile (0.80 km) upstream. Floating dock (impounded) A floating dock , floating harbour or wet dock is a dock alongside a tidal waterway which maintains a 'constant' level, despite the changing tides. At the most basic level, a floating dock

385-530: Is isolated from tidal water by a lock gate , at least, although in many dock systems the entrance is more complex than this. The first wet dock was Howland Great Wet Dock or Greenland Dock, built in London at the end of the 17th century. This was not a commercial dock and had no warehouses, but was intended solely for ship replenishment and refitting. In 1715 the first commercial wet dock, Liverpool 's Old Dock , opened. Early docks were of simple construction:

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420-522: The Chat Moss bog with the Liverpool and Manchester Railway . The canal was carried over the bog on a high embankment. Jessop also identified sources of water and built reservoirs , so that the canal was in no danger of running dry. Having seen to all of the important details Jessop returned to England, leaving a deputy in charge to complete the canal. This was finally done in 1805. It seems that Jessop

455-597: The Dublin end. In 1772 a private company was formed to complete the canal, and consulted John Smeaton. Smeaton sent Jessop to take control of the project as principal engineer. Jessop re-surveyed the proposed line of the canal and carried the canal over the River Liffey , via the Leinster Aqueduct. He also drove the canal across the great Bog of Allen , a feat comparable with George Stephenson 's crossing of

490-585: The Thames at Brentford , a length of ninety miles. Jessop was appointed Chief Engineer to the Canal Company in 1793. The canal was especially difficult to plan because, whereas other canals tended to follow river valleys and only crossed a watershed when unavoidable, the new canal had to cross the rivers Ouse, Nene and others. An aqueduct was built at Wolverton to carry the canal across the Ouse valley. Whilst

525-468: The ebbing tide thus interfering with the wharf-side level of every ship in the basin. A half tide dock is a partially tidal dock. They need have no gate, but as the tide ebbs a raised sill or weir on the floor of the dock prevents the level dropping below a certain point, meaning that the ships in the dock remain afloat, although they still fall with the first ebb of the tide. Half tide docks were only useful for ships of shallow draught, in areas with

560-533: The lighthouse burnt down. John Smeaton , a leading civil engineer , drew up plans for a new stone lighthouse and Josias became responsible for the overseeing the building work. The two men became close friends, and when Josias died in 1761, two years after the completion of the lighthouse, William Jessop was taken on as a pupil by Smeaton (who also acted as Jessop's guardian), working on various canal schemes in Yorkshire . Jessop worked as Smeaton's assistant for

595-470: The Chief Engineer for the docks, with Ralph Walker as his assistant. In 1799 separate proposals were put forward for a canal from London to Portsmouth and for a tramway carrying horse-drawn carriages over the same route. The first part of the proposed Surrey Iron Railway was to be from Wandsworth to Croydon , and Jessop was asked for his opinion on the two opposing schemes. He declared that

630-518: The Thames, albeit only beyond the low-water mark. This was the first time that anyone had made a tunnel pass underneath the actual water of any river. However, it remained to complete the excavation under the high-water mark, and this Trevithick was unable to do, owing to breakthroughs of quicksand. The failure of the Thames Archway project led engineers to conclude that "an underground tunnel

665-489: The first industrialised ports, Liverpool was at the forefront of dock development from the early 18th century. A network of inter-linked docks developed along the length of the River Mersey shoreline. These were floating docks, with access through a number of tidal basins and half tide docks . Ships could move through the interlinked docks 24 hours a day without moving into the tidal River Mersey, which would necessitate

700-408: The harbour and the river, the intention was that the basin would itself be used as an entrance lock: rather than locking each ship through one-by-one, ships could wait for the tide inside the basin and then the outer lock gates could both be opened allowing all to leave and arrive together. For a port with such a convoluted and tide-dependent approach as Bristol's, any easing of access was valuable. As

735-421: The harbour now need never be connected directly to the tidal waters, its water level could be held constant, without even the small variation of the hours around high tide. At Bristol, Jessop controlled the height of the harbour water by a broad weir , built as a dam across the previous route of the river. Levels were maintained by the flow of the small River Frome which still flowed into the harbour. As one of

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770-724: The next phase was authorized for a line from Croydon via Merstham to Godstone in Surrey. Jessop was again appointed Chief Engineer, with his son Josias as his assistant. The line reached Merstham but was never continued to Godstone. The total distance of the tramway from Wandsworth was 18 miles (29 km). The tramway was eventually overtaken by the advent of steam locomotives. From 1784 to 1805 Jessop lived in Newark in Nottinghamshire, where he twice served as town mayor. In his later life, Jessop became increasingly inflicted by

805-564: The number of ships passing through it. One of the first large fully floating docks was that of Bristol's Floating Harbour , built in 1809 to a plan by William Jessop . This involved the diversion of the River Avon (Bristol) away from its previous route through the harbour and into a new channel at the New Cut . Entrance to the harbour was now gained through an entrance basin, at what is now Cumberland Basin . Although linked by locks to

840-553: The post of engineer to the Lancaster Canal Company, an appointment that helped to establish Rennie's reputation. When Jessop was consulting engineer to the Ellesmere Canal Company, in 1793, the company appointed the relatively unknown Thomas Telford as resident engineer. Telford had no previous experience as a designer of canals, but with Jessop's advice and guidance, Telford made a success of

875-669: The project. He supported Telford, even when the Company thought that the latter's designs for aqueducts were too ambitious. In 1789 Jessop was appointed chief engineer to the Cromford Canal Company. The proposed canal was intended to carry limestone, coal and iron ore from the Derwent and upper Erewash valleys and join the nearby Erewash Canal. The important features of this canal are the Derwent Viaduct, which

910-735: The surface to build it. Jessop built the Butterley Reservoir above the tunnel, extending for 50 acres (20 ha). In 1790 Jessop founded, jointly with partners Benjamin Outram , Francis Beresford and John Wright, the Butterley Iron Works in Derbyshire to manufacture (amongst other things) cast-iron edge rails – a design Jessop had used successfully on a horse-drawn railway scheme for coal wagons between Nanpantan and Loughborough , Leicestershire (1789). Outram

945-533: The three-arch stone aqueduct was being built, a set of nine temporary locks were used to carry the canal down one side of the valley and up the other. The aqueduct failed in 1808, and was replaced by an iron one in 1811, the iron trough design sharing a similar structure to Longdon-on-Tern Aqueduct and the Pontcysyllte Aqueduct built by Thomas Telford . It is known as the Cosgrove aqueduct and

980-645: The tramway was a better scheme, as a canal would require too much water and would unduly reduce the supply in the River Wandle . It was agreed to build a tramway from Wandsworth to Croydon, as well a building a basin at Wandsworth. Jessop was appointed Chief Engineer of the project in 1801. In 1802 the Wandsworth Basin and the line were completed. There seems to be doubt as to the gauge of the line with some estimates stating 4 ft 2 in (1.27 m) and others stating 4 ft 8½ in. In 1803,

1015-685: Was a single span viaduct carrying the canal over the River Derwent , and the Butterley Tunnel (formerly the Ripley Tunnel). In 1793, the Derwent Viaduct partially collapsed, and Jessop shouldered the blame, saying that he had not made the front walls strong enough. He had the viaduct repaired and strengthened at his own expense. The Butterley Tunnel was 2,966 yards (2712m) long, 9 ft (2.7 m) wide and 8 ft (2.4 m) high and required thirty-three shafts to be sunk from

1050-621: Was an English civil engineer , best known for his work on canals , harbours and early railways in the late 18th and early 19th centuries. Jessop was born in Devonport, Devon , the son of Josias Jessop, a foreman shipwright in the Naval Dockyard. Josias Jessop was responsible for the repair and maintenance of Rudyerd's Tower, a wooden lighthouse on the Eddystone Rock . He carried out this task for twenty years until 1755, when

1085-469: Was closely involved with the canal in Ireland until about 1787, after which time, other work flowed in. Jessop was a very modest man, who did not seek self-aggrandizement . Unlike other engineers, he was not jealous of rising young engineers, but rather encouraged them. He would also recommend another engineer if he was too busy to be able to undertake a commission himself. He recommended John Rennie for

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1120-505: Was completed. The Grand Junction Canal was enormously important in encouraging trade between London and the Midlands. The West India Docks , built on the Isle of Dogs , was the first large wet docks built in the Port of London . Between 1800 and 1802 a wet dock area of 295 acres (1.19 km ) was created with a depth of 24 ft (7.3 m), and accommodating 600 ships. Jessop was

1155-521: Was concerned with the production of ironwork and equipment for Jessop's engineering projects. The Oxford Canal had been built by James Brindley and carried coal to large parts of southern England. However it did not provide a sufficiently direct route between the Midlands and London. As a result, a new canal was proposed to run from the Oxford Canal at Braunston , near Rugby , and to end at

1190-456: Was designed and built by Benjamin Bevan . Two tunnels also had to be built, at Braunston and Blisworth . The Blisworth Tunnel caused great problems, and was unfinished when the rest of the canal was ready. In fact Jessop considered abandoning it and using locks to carry the canal over the ridge. Jessop's temporary solution was a railway line laid over the ridge to carry traffic until the tunnel

1225-417: Was to bore a pilot tunnel or 'driftway' starting from a shaft to be sunk in Rotherhithe (i.e. from the south bank). The driftway was supposed to drain the surrounding bedrock and then be enlarged into a full, brick-arched tunnel which would accommodate two-way vehicular traffic. Unfortunately the firm strata anticipated were mostly sand and gravel with pockets of quicksand . After a year Vazie had only driven

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