56-580: The Somerset Coal Canal (originally known as the Somersetshire Coal Canal ) was a narrow canal in England, built around 1800. Its route began in basins at Paulton and Timsbury , ran to nearby Camerton , over two aqueducts at Dunkerton , through a tunnel at Combe Hay , then via Midford and Monkton Combe to Limpley Stoke where it joined the Kennet and Avon Canal . This link gave
112-415: A Boulton & Watt Steam Pumping Station, capable of lifting 5,000 tons of water in 12 hours, were built to the latest design with metal plate clad wooden gates. The two images show a spillway drain from c. 1796 (uncovered in 2009–10) at Upper Midford , a location where a caisson to take the canal from the 180 ft (55 m) level to the 134 ft (41 m) level at Midford Aqueduct
168-410: A rack-and-pinion , removable weights or a small winch could overcome inertia and move the caissons. In a practical demonstration at Hampstead Road Congreve later elected to deploy an air compressor releasing into one caisson, estimating that one man could achieve raising and lowering in three minutes—the company's enabling act did not permit the installation of stationary steam engines . However it
224-573: A Mile to pay for Half a Mile, and of a Ton as a Quarter of a Ton; Rates for Wharfage to be determined by the Company. In addition to the above Rates, One Shilling per Ton is paid on all Goods to the Lock Fund, which also receives Three Farthings per Ton from the Coal Canal company. The boats were weighed at Midford, where a weigh house was built in 1831. Boats were floated into a one-ended lock,
280-409: A balance (or geometrical) lift without payment, on condition that if successful they were to have £17,300 and a royalty of 4 pence per ton of goods passed. The design of the caisson lock at Combe Hay was not a success: on 15 February 1798 the first descent failed. Mr Weldon (the inventor) made one successful descent on 7 June and said "I will undertake to pass 1,500 tons of goods through
336-526: A little loss of water when operating compared with a conventional boat lock. The caisson lock was first demonstrated at Oakengates on a now lost section of the Shropshire Canal in 1792, where its inventor, Robert Weldon (b:?1754, d:1810) built a half-scale model. He claimed that his design would solve the problem of water supply in dry seasons or at greater elevations, be cheaper than building aqueducts or tunnels, and be quicker to operate than
392-488: A longer alignment up the slope was constructed, with a Boulton & Watt Steam Pumping Station, capable of lifting 5,000 tons of water in 12 hours, used to recirculate the water. In April 1815 the Regents Canal Company built a double caisson lock (or "hydro-pneumatic lock" ) at the site of the present-day Hampstead Road Lock , north London. The designer was military engineer William Congreve . Here
448-492: A lower level at this point. The Lock Fund created in 1802 was to have paid for the construction of the locks, but because there was little regular traffic on the branch, the company built one lock, an aqueduct over the Midford Brook, and a short tramway to bridge the gap. This contributed to the economic failure of the branch, and its replacement by a tramway in 1815. The tramway was laid along the former canal's towpath. It
504-485: A navigable Canal, with certain Railways and Stone Roads, from several Collieries in the county of Somerset, to communicate with the intended Kennet and Avon Canal, in the parish of Bradford, in the county of Wilts " of 1794, and further detailed surveys were carried out by Robert Whitworth and John Sutcliffe, who was then appointed as chief engineer. In May 1795, tenders were invited for the first section to be built from
560-479: A retaining wall was discovered in the south embankment continuing for about 100 m (110 yd), possibly built as a repair to a weak section of canal banking. Vertical infills of white clay have been used along this wall. The canal has been studied for many years with exploration and restoration work being undertaken in Wellow and elsewhere. Particular effort, so far unsuccessful, has been put into trying to find
616-471: The Somerset coalfield (which at its peak contained 80 collieries) access east toward London. The longest arm was 10.6 miles (17.1 km) long with 23 locks . From Midford an arm also ran via Writhlington to Radstock , with a tunnel at Wellow . A feature of the canal was the variety of methods used at Combe Hay to overcome height differences between the upper and lower reaches: initially by
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#1732772257534672-488: The submerged, sealed box (the " caisson ", from the French for "large chest" ) being heavily ballasted to achieve neutral buoyancy , so it was never possible in ordinary operation to lift it to water level to allow a descending boat to float in. Instead, a masonry chamber (" cistern ") was built with walls higher than the water level in the top pound and itself filled completely with water, so that even at its upper position
728-405: The 1870s when the decline in output of coal from the various Somerset coalpits, along with competition from the railways, dramatically reduced the canal's profitability. When the main pump at Dunkerton failed it was not replaced and there was not sufficient water for continual operation of the locks. The canal went into liquidation in 1894; it closed in 1898 and was finally abandoned in 1904 when it
784-400: The 1960s. It may no longer be feasible to reinstate the original locks 16, 17, 18 and 19 structures for this section. At Upper Midford the canal is blocked entirely at the accommodation bridge by the 40-foot (12 m) high embankment of the railway that crosses it. Most of the canal features along the entire route are on private land but the towpath survives in places as a right of way, while
840-659: The 60 ft (18 m) deep pool of water, which never left the lock. The box was demonstrated to the Prince Regent (later George IV ), but had engineering problems and was never successful commercially or built elsewhere. It was temporarily replaced with an inclined plane by Benjamin Outram who had successfully installed inclined planes at the Peak Forest Canal in Derbyshire, whilst 22 locks and
896-526: The Wikimedia System Administrators, please include the details below. Request from 172.68.168.133 via cp1102 cp1102, Varnish XID 549101070 Upstream caches: cp1102 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 05:37:37 GMT Caisson lock The caisson lock is a type of canal lock in which a narrowboat is floated into a sealed watertight box and raised or lowered between two different canal water levels. It
952-406: The box remained below the surface. The May 1799 test, above, occurred when a party of investors was aboard the vessel and they nearly suffocated before they could be freed. Work on the second lock was suspended (the third lock had not been started) and early in the following year an inclined plane , to carry boats’ cargoes in wheeled tubs, was built instead. Eventually a flight of nineteen locks on
1008-650: The building of a flight of 19 locks to replace it, the use of which would incur an additional toll of one shilling per ton on all traffic. This was vigorously opposed by the owners of the Kennet and Avon Canal and the Wilts and Berks Canal , on the grounds that the price of coal to their customers would be too high. After negotiation, the company obtained a new act of Parliament, the Somersetshire Coal Canal Navigation Act 1802 ( 42 Geo. 3 . c. xxxv), on 30 April 1802, which authorised
1064-465: The canal joins the Kennet and Avon at Dundas Aqueduct was restored during the 1980s and is now a thriving marina with moorings. Excavations of the old stop lock (at the junction with the Kennet and Avon Canal ) showed that this had originally been a broad (14 feet, 4.3 m) lock that at some point was narrowed to 7 feet (2.1 m) by moving the lock wall. Work started in 2013 to reveal and excavate
1120-572: The canal lies in a largely agricultural area, dotted with small villages linked by minor roads. Several stretches of the Paulton and Timsbury basins branch are easily visible, and various stretches and features were surveyed in 2014. Full restoration of the entire length from Paulton to Dundas is being explored. Four locks on the original canal route at Combe Hay have been buried; one by a 20-foot (6 m) railway embankment, and three overfilled by 10 to 20 feet (3–6 m) with building waste since
1176-504: The canal route from Limpley Stoke to Camerton, where it joined the existing 1882 branch line from Hallatrow to Camerton. This opened in 1910 for passenger and goods traffic, closed for the First World War , re-opened after the war, ran for passengers only for two more years in the mid-1920s and finally closed to all traffic in the 1950s. The line was used in the 1950s Ealing comedy film The Titfield Thunderbolt . The route of
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#17327722575341232-413: The company substituted conventional locks. A patent granted to Jonathan Brownill, a cutler from Sheffield, on 1 May 1828, while in principle operating as an open-air balance lock , was described as using three caissons . The main caisson was connected by ropes passing over grooved pulleys to two smaller, counterbalancing caissons. Brownill's innovation was to place wedges ("inclined planes") opposite
1288-462: The direction of John Rennie who presented the report on 14 October 1793 estimating the cost of construction of the canal at £80,000. Smith, who also worked at the Mearns Pit at High Littleton , made the original observations leading to his important stratification theory by observing the dips in the geological strata through which the canal was cut. Smith became Surveyor to the company, but
1344-559: The drydock next to the eastern Paulton Basin. This drydock appears to be the largest drydock anywhere on the canal system in England, being about 30 feet (9.1 m) wide and 83 feet (25 m) long, large enough for three full-length narrowboats to be worked on at the same time. The drainage culvert at the southeast corner of the drydock was rebuilt in December 2013, and the drydock itself completely excavated in April 2014. The entrance to
1400-490: The drydock, at the western end, was surmounted by a bridge, partially demolished in 2002 but rebuilt during 2014. Excavations began in May 2014 at Terminus Bridge; the abutments were found to be in poor condition; an earth bund between the abutments carried the public footpath and stopped the water draining from the Paulton and Timsbury Basins. A new earth bund was installed about 25 m (27 yd) west of Terminus Bridge to stop
1456-628: The formation of a separate body called "The Lock Fund of the Somerset Coal Canal Company", with powers to raise the sum of £45,000. The money was raised by the Kennet and Avon, the Wilts and Berks and the Somerset Coal Canal each contributing £15,000, and the one shilling surcharge was to be levied until the capital had been repaid, after which it would cease. The act set the tonnage rates to be charged: Fractions of
1512-500: The fuel that powered the nearby city of Bath. By the 1880s, coal production declined as the various pits either ran out of coal or were flooded and then closed. In 1896 the main pump at Dunkerton, which maintained the canal water level, failed. The resultant lowering in level meant that only small loads could be transported, which reduced revenue, thus the canal company could not afford a replacement pump. The canal became disused after 1898 and officially closed in 1902, being sold off to
1568-483: The gate closed and the water drained. This left the boat resting on a cradle suspended by angled rods attached to a beam which took the weight of the boat. One-pound weights were then added to a pan, with one pound being equivalent to one hundredweight (112 pounds or 51 kilograms), until the system was in equilibrium, then the weight was recorded. The weigh house at Midford was one of only four known to have been built in England and Wales. The canal opened in 1805 and
1624-447: The later railway between Midford to Wellow has been surfaced to form part of National Cycle Route 24 . It has been proposed that a statue, commissioned by Sustrans , of William Smith , the father of English Geology, will be sited next to the path on the line of the canal commemorating his work as its surveyor and his recognition of the significance of rock strata. The 1 ⁄ 4 -mile (400 m) stretch at Brassknocker Basin where
1680-427: The latter caisson, which accordingly rose as the first sank. A connecting underwater chain passing through rollers, while not in itself doing any work, controlled the relative positions. Boats were admitted through double gates; the inside ones on the caisson "adjusted to fit close [ sic ] to those of the outer". Congreve's patent then envisaged that having achieved "absolute equipoise" ( neutral buoyancy )
1736-426: The lock in 12 hrs". Tenders were invited on 28 June for further constructions. Two more attempts to use the lock took place on 11 April and 2 May, but only the latter was successful. By 22 August 1799 the second rebuilding of the caisson had been abandoned. It was replaced by three locks and an inclined plane trackway, but the trackway was not successful either, and the company proposed to raise more money to finance
Somerset Coal Canal - Misplaced Pages Continue
1792-512: The meadow terminus by tramways; this required the construction of three tramway bridges over the Cam brook. A further bridge at Upper Radford was required over the canal; at this point tramways connected the Withy Mills and Radford workings. The course of the Cam brook was modified at various places to protect the canal from erosion. In 1799 William Whitmore and his partner, Norton, offered to build
1848-456: The meadows near Goosehard (or Gooseyard) near Paulton to Hopyard in the parish of Camerton. In June 1795 a contractor, Houghton & Son from Shropshire, started the terminus at Paulton meadows using local labour. This first section of the canal was completed on Monday 1 October 1798; the first load of coal carried on the canal was delivered to Bath via Dunkerton. Some 14 collieries at Timsbury and Paulton were connected to their respective basins in
1904-465: The mills along it had water rights. Each narrow boat travelling through the series of locks (22 of them each 6 ft (1.8 m) deep) with a 25-ton load of coal caused 85 tons of water to be discharged into the brook below the locks. As a result, the canal was designed with all 22 locks in one flight near Combe Hay and a pumping engine to raise water from the Cam; this was the first canal to depend entirely on pumping. A potential solution to
1960-400: The motivation was, principally, water supply problems but also to effect a quicker passage of vessels, as those going in opposite directions could pass in the lock. The caissons—always submerged, as at Combe Hay —were without bottoms and were arranged so that their sides dropped into deep underwater channels formed by "minor walls" inside the main walls. The vertical movement of the two caissons
2016-413: The number of surface locks his design could replace. He patented his invention as the 'Hydrostatick Caisson Lock'. The full-sized box, or "trunk", would probably have displaced about 270 tonnes and weighed about 170 tonnes, including the water in it, so about 100 tonnes of ballast would have been needed to give neutral buoyancy . The box would have needed to be strong enough to withstand
2072-426: The pressure of 50 ft (15 m) of water i.e. about 22 psi (150 kPa) gauge pressure at the bottom of the chamber. The first lock was completed in 1797 under Weldon's supervision. The device was demonstrated to the Prince Regent (later George IV ), but was found to suffer from various engineering problems, possibly caused by the soft fuller's earth rock stratum in the area. The system depended on
2128-893: The site of the second and third caisson locks at Combe Hay. In October 2006 a grant of £20,000 was obtained from the Heritage Lottery Fund , by the Somersetshire Coal Canal Society in association with Bath & North East Somerset Council and the Avon Industrial Buildings Trust to carry out a technical study on one of the locks and associated structures at Combe Hay. Many of the locks and associated workings are listed buildings . Download coordinates as: 51°20′02″N 2°24′32″W / 51.334°N 2.409°W / 51.334; -2.409 Paulton Too Many Requests If you report this error to
2184-503: The tramroads which served Old Grove, Prior's, Tyning and Hayeswood pits, with a branch line to Amesbury and Mearns pits. Parts of this line were still in use in 1873, probably all carrying horse-drawn wagons of coal. Tramroads on the southern side of the Paulton basin served Brittens, Littleborrok, Paulton Ham, Paulton Hill, Simons Hill terminating at Salisbury Colliery. In addition the Paulton Foundry used this line. The entire line
2240-484: The tramway. It finally closed in 1874 with the Somerset and Dorset Railway 's extension to Bath , built along its route from Radstock to Midford. Another branch line was constructed in 1882 from Hallatrow to Camerton, running alongside the canal for the last 1 + 1 ⁄ 2 miles (2 km) of its route. The Great Western Railway built a railway line (the Bristol and North Somerset Railway ) over some parts of
2296-446: The use of caisson locks ; when this method failed an inclined plane trackway; and finally a flight of 22 conventional locks . The Radstock arm was never commercially successful and was replaced first with a tramway in 1815 and later incorporated into the Somerset and Dorset Joint Railway . The Paulton route flourished for nearly 100 years and was very profitable, carrying high tonnages of coal for many decades; this canal helped carry
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2352-480: The various railway companies who were expanding their networks. In September 2014, restoration work began on the canal section from Paulton to Radford, with the aim of restoring the entire canal to navigation in the future. The largest canal drydock in England has been revealed at Paulton; culverts and bridges nearby are being reinstated or rebuilt; and about 2 ⁄ 3 mile (1 km) of canal from Paulton to Radford has been in water since mid-2015. In 1763 coal
2408-403: The villages of Paulton and Timsbury was the terminus of the northern branch of the Somerset Coal Canal and was a central point for at least 15 collieries around Paulton , Timsbury and High Littleton , which were connected to the canal by tramroads. Timsbury basin was some 600 ft (180 m) to the west of Paulton basin. On the northern side of Timsbury basin was the terminus for
2464-466: The water and allow work to continue on the bridge. During excavations a drainage culvert was discovered about 20 m (22 yd) west of Terminus bridge. Work resumed in September and November 2014 to batter and reshape the canal embankments. Excess topsoil was removed and the towpath reinstated on the stretch to the east from Terminus bridge for about 200 m (220 yd). On the same stretch
2520-409: The water supply problem was the use of caisson locks as proposed by Robert Weldon , three of which could replace the 22 conventional locks, because it wasted no water, but the technology had only been tried in a one-third scale prototype. Each lock was 80 ft (24 m) long and 60 ft (18 m) deep and contained a closed wooden box which could take a barge. This box moved up and down in
2576-542: Was discovered in Radstock and mining began in the area, but transport was a major problem because of the poor state of the roads. This cost and the potential for cheaper delivery of coal from south Wales via the Monmouthshire Canal led to the proposal for a canal which could transport the coal to Bath and Wiltshire . Initial surveys were conducted during 1793 by William Jessop and William Smith under
2632-585: Was dismissed in April 1799, apparently because he had used his position as surveyor to buy a local house at advantageous terms. He then set himself up in a private practice in Bath but was re-engaged by the company in 1811, to provide advice when repairs became necessary to the canal bed. The canal was authorised by an act of Parliament , the Somersetshire Coal Canal Act 1794 ( 34 Geo. 3 . c. 86), entitled "An Act for making and maintaining
2688-524: Was disused by 1871 as were the collieries it served. The area has been designated as an 'area of special architectural or historic interest, the character or appearance of which it is desirable to preserve or enhance' under section 69 of the Planning (Listed Buildings and Conservation Areas) Act 1990 . The first railway to affect the canal was the Bristol and North Somerset Railway 's Frome to Radstock line completed in 1854 which took traffic away from
2744-406: Was effected by a balance pipe ("the channel of communication") passing under the lock floor between the two caisson chambers (but with a slight upturn to reach above the water levels), so that causing an increase of water level in one caisson ("the water of compression") displaced air through the pipe, thus forcing a corresponding decrease in the water level in the other. This increased the buoyancy of
2800-457: Was found the fastest overall time was six minutes and that the effort required rendered the operator "incapable of further exertion". Furthermore, as the operation of the device depended upon air pressure inside the caissons (whether the means of moving them was by varying this air pressure or otherwise) when contractor Henry Maudslay delivered them and they were found to leak air, the scheme failed. In 1818, after many unsuccessful repair attempts,
2856-439: Was invented in the late 18th century as a solution to the problem posed by the excessive demand for water when conventional locks were used to raise and lower canal boats through large height differences. Such locks, each of which would only raise and lower boats through small height differences of a few feet, would not suffice when large height differences had to be tackled nor when water was in short supply. The caisson (or caisoon)
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#17327722575342912-683: Was proposed. Each caisson would have had such a drain for maintenance purposes over the exit arch made to the same dimensions. The following extract from the Bath Herald newspaper provides the details of the chosen sites: 14 Jun 1798 Travel: Somerset coal canal – caisson cisterns to be formed at Combe Hay & nr. Midford. Sealed proposals reqd. on embanking & excavation with the masonry; or each separately – send to sub-committee, Waldegrave Arms, Radstock 20 Jul Plans & specs. on appl. For further Newspaper articles see s:Bath Georgian Newspaper - Somerset Coal Canal located between
2968-402: Was single-line with passing places every 600 yards (550 m), and was originally laid using cast iron plates on stone block sleepers, but was relaid using wrought iron plates. Data from Jim Shead's Waterways Information. The fall over the route is 135 ft (41 m), which meant problems with supplying adequate water. The Cam brook was an inadequate source of water above Camerton, and
3024-645: Was sold to the Great Western Railway for £2,000, and used as a branch of the Bristol and North Somerset Railway. The closure caused problems across the Somerset coalfield especially to the pits along the Paulton branch, which had relied on the canal for transportation. When the Radstock branch was constructed, it was intended to link it to the main line of the Paulton branch at Midford, which was at
3080-453: Was thought to be one solution, although it transpired that the technology of the day was not capable of achieving this type of construction economically. It was designed primarily as a water-saving measure, and also was an attempt to minimise construction costs compared with other engineering solutions of the time. In use it was capable of replacing up to seven conventional locks. Other design benefits were speed of boat descent/ascent, and only
3136-468: Was used for passenger traffic as well as coal. In 1814 the Benedictine monks who came to Downside Abbey are said to have used the canal for the last stage of their journey. Another cargo carried by the canal was limestone from Combe Down . The peak level of cargo carried was in 1838 at 138,403 tons resulting in over £17,000 of tolls being paid. Cargoes of over 100,000 tons were common until
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