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James Green (engineer)
Encyclopedia
James Green was a noted civil engineer
and canal
engineer, who was particularly active in the South West of England
, where he pioneered the building of tub boat
canals, and inventive solutions for coping with hilly terrain, which included tub boat lift
s and inclined planes
. Although dismissed from two schemes within days of each other, as a result of construction problems, his contribution as a civil engineer was great.
, the son of an engineering family. He learned much from his father, by whom he was employed until the age of 20. He then worked with John Rennie on a number of projects around the country, until 1808, when he moved to Devon
, and established a base at Exeter
. He submitted plans for the rebuilding of Fenny Bridges, in East Devon, which had collapsed only 18 months after their previous reconstruction. The plans were accepted, and Green became the Bridge Surveyor for the County of Devon. By 1818 he had been promoted to Surveyor of Bridges and Buildings for the county, and held this position until 1841. These official duties did not prevent him from involvement in many private projects.
His initial involvement with canals in the West Country
included his appointment as engineer for the Braunton Canal and drainage scheme
and the Exeter and Crediton Canal. This project started in 1810, and was abandoned in its early stages, and was never completed. He was also involved with extending and enlarging the Exeter Ship Canal
, a project which started in 1820 and lasted for seven years.
s, which were fairly small and capable of transporting between five and eight tons of goods, and rather than using conventional locks to alter the level of the canal, advocated the use of vertical lifts
and inclined planes
.
s, which were located near the top of the planes. The sixth one, at Hobbacott, was 935 ft long (285 m) and raised the canal by 225 ft (68.6 m). It was powered by a system of buckets which descended and ascended in a pair of wells. Each bucket was capable of holding 15 tons of water, and they were attached to either end of a chain, which passed over a drum. The buckets were arranged so that when one was at the top of its well, the other was at the bottom. The top bucket was charged with water, and its weight then caused it to descend, raising the other bucket and a tub boat at the same time. When it reached the bottom, the water was automatically discharged, and ran along an adit
to empty into the bottom level of the canal. The process was quick and efficient, raising a tub boat in about four minutes, which was half the time required when the standby 16 hp steam engine
had to be used.
Green took his inspiration for the methods of operating the planes from the work of Robert Fulton
, but brought his own engineering skills to make a workable system.
Green's next assignment was more ambitious. He was engineer for the Somerset section of the Grand Western Canal. The Devon
section had been built as part of a proposed scheme to link the Bristol Channel
to Exeter
, but the scheme had foundered due to lack of finances, and the section near Tiverton was isolated, with the link to Taunton
never having been built. In 1829, Green again proposed a tub-boat canal with inclined planes, but by 1830, this had been altered to seven vertical boat lift
s and one inclined plane. Green acknowledged the ideas of Dr James Anderson of Edinburgh, who had proposed vertical boat lifts in 1796, but also noted that the proposals required interpretation in order to make them workable. Various prototypes had been built around the country, but none had proved successful.
There were delays in the commissioning of the boat lifts, as Green struggled with the engineering problems. The lift consisted of two chambers, each holding a caisson, which was joined to the other by chains which passed over a series of wheels. Since a boat displaces its own weight of water, a caisson with a boat in it balances one with no boat in it. In order to make the system work, the top caisson was filled with about 2 inches (5 cm) of water more than the bottom one, and motion was provided by the extra weight of water, which was about a ton. The difficulties arose when the descending caisson reached the water in the bottom chamber. Anderson had suggested that the water level should be lower than the level of the canal, so that the caisson could sink low enough for the boat to float out. Green had not implemented this, and ultimately the problem was solved by constructing what amounted to a lock at the bottom, so that the boat floated out into the lock and descended the last 3 ft (0.9 m) as it would in a conventional lock.
The inclined plane was more problematical. Green seems to have made an error in calculation, which resulted in the buckets being much too small. On the Bude Canal, he had used a 15 ton bucket to raise a five ton boat. Here he had designed a 10 ton bucket, and the loaded boats weighed about 8 tons. Commissioning tests indicated that a bucket capable of holding 25 tons of water would be needed, but the shafts were not big enough. The novel power source had to be abandoned, to be replaced by a steam engine
. Green was dismissed in January 1836.
, but Green had to admit that he could not complete the inclines, as he had underestimated the cost of their construction by a huge margin. He was dismissed from the project on 30 January 1836, just three days after his dismissal from the Grand Western project.
and the Newport Docks
, and working on the South Devon Railway
. He remained responsible for hundreds of structures in Devon until he was 60, and died, aged 68, in 1849. At the time of his death his son Joseph D. Green was resident engineer at Bristol docks.
Green had a prodigious workload for much of his career as an engineer, and it is not surprising that some mistakes were made. Nevertheless he made a huge contribution to civil engineering in South West England
.
Civil engineer
A civil engineer is a person who practices civil engineering; the application of planning, designing, constructing, maintaining, and operating infrastructures while protecting the public and environmental health, as well as improving existing infrastructures that have been neglected.Originally, a...
and canal
Canal
Canals are man-made channels for water. There are two types of canal:#Waterways: navigable transportation canals used for carrying ships and boats shipping goods and conveying people, further subdivided into two kinds:...
engineer, who was particularly active in the South West of England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
, where he pioneered the building of tub boat
Tub boat
A tub boat was a type of unpowered cargo boat used on a number of the early English and German canals. The English boats were typically long and wide and generally carried to of cargo, though some extra deep ones could carry up to . They are also called compartment boats or container boats.The...
canals, and inventive solutions for coping with hilly terrain, which included tub boat lift
Tub boat lift
A tub boat lift is a type of boat lift designed to lift tub boats between different elevations of a canal. Tub boats are small boats used to transport coal and other minerals, sometimes working singly, sometimes in long trains. A tub boat lift lifts the boat out of the water...
s and inclined planes
Canal inclined plane
An inclined plane is a system used on some canals for raising boats between different water levels. Boats may be conveyed afloat, in caissons, or may be carried in cradles or slings. It can be considered as a specialised type of cable railway....
. Although dismissed from two schemes within days of each other, as a result of construction problems, his contribution as a civil engineer was great.
Early career
James Green was born in BirminghamBirmingham
Birmingham is a city and metropolitan borough in the West Midlands of England. It is the most populous British city outside the capital London, with a population of 1,036,900 , and lies at the heart of the West Midlands conurbation, the second most populous urban area in the United Kingdom with a...
, the son of an engineering family. He learned much from his father, by whom he was employed until the age of 20. He then worked with John Rennie on a number of projects around the country, until 1808, when he moved to Devon
Devon
Devon is a large county in southwestern England. The county is sometimes referred to as Devonshire, although the term is rarely used inside the county itself as the county has never been officially "shired", it often indicates a traditional or historical context.The county shares borders with...
, and established a base at Exeter
Exeter
Exeter is a historic city in Devon, England. It lies within the ceremonial county of Devon, of which it is the county town as well as the home of Devon County Council. Currently the administrative area has the status of a non-metropolitan district, and is therefore under the administration of the...
. He submitted plans for the rebuilding of Fenny Bridges, in East Devon, which had collapsed only 18 months after their previous reconstruction. The plans were accepted, and Green became the Bridge Surveyor for the County of Devon. By 1818 he had been promoted to Surveyor of Bridges and Buildings for the county, and held this position until 1841. These official duties did not prevent him from involvement in many private projects.
His initial involvement with canals in the West Country
West Country
The West Country is an informal term for the area of south western England roughly corresponding to the modern South West England government region. It is often defined to encompass the historic counties of Cornwall, Devon, Dorset and Somerset and the City of Bristol, while the counties of...
included his appointment as engineer for the Braunton Canal and drainage scheme
Braunton Canal
The Braunton Canal is a cut made to straighten the course of the upper section of the River Caen, known as Braunton Pill, and to provide a new quay for the village of Braunton in North Devon, England...
and the Exeter and Crediton Canal. This project started in 1810, and was abandoned in its early stages, and was never completed. He was also involved with extending and enlarging the Exeter Ship Canal
Exeter Canal
The Exeter Ship Canal, sometimes just called the Exeter Canal, downstream of Exeter, Devon, England was built in the 1560s which means it pre-dates the "canal mania" period and is one of the oldest artificial waterways in the UK.-History:...
, a project which started in 1820 and lasted for seven years.
Tub boats and inclined planes
James Green brought his own individual style to canal building. He was faced with the engineering problems of building canals in hilly terrain, where the water supply was limited. His solution was to advocate the use of tub boatTub boat
A tub boat was a type of unpowered cargo boat used on a number of the early English and German canals. The English boats were typically long and wide and generally carried to of cargo, though some extra deep ones could carry up to . They are also called compartment boats or container boats.The...
s, which were fairly small and capable of transporting between five and eight tons of goods, and rather than using conventional locks to alter the level of the canal, advocated the use of vertical lifts
Tub boat lift
A tub boat lift is a type of boat lift designed to lift tub boats between different elevations of a canal. Tub boats are small boats used to transport coal and other minerals, sometimes working singly, sometimes in long trains. A tub boat lift lifts the boat out of the water...
and inclined planes
Canal inclined plane
An inclined plane is a system used on some canals for raising boats between different water levels. Boats may be conveyed afloat, in caissons, or may be carried in cradles or slings. It can be considered as a specialised type of cable railway....
.
The Bude Canal
The first project that used this approach was the Bude Canal, for which he presented a report in 1818, and then acted as engineer from 1819 to 1825. The plans included three conventional locks and six inclined planes. Five of the planes were powered by water wheelWater wheel
A water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power. A water wheel consists of a large wooden or metal wheel, with a number of blades or buckets arranged on the outside rim forming the driving surface...
s, which were located near the top of the planes. The sixth one, at Hobbacott, was 935 ft long (285 m) and raised the canal by 225 ft (68.6 m). It was powered by a system of buckets which descended and ascended in a pair of wells. Each bucket was capable of holding 15 tons of water, and they were attached to either end of a chain, which passed over a drum. The buckets were arranged so that when one was at the top of its well, the other was at the bottom. The top bucket was charged with water, and its weight then caused it to descend, raising the other bucket and a tub boat at the same time. When it reached the bottom, the water was automatically discharged, and ran along an adit
Adit
An adit is an entrance to an underground mine which is horizontal or nearly horizontal, by which the mine can be entered, drained of water, and ventilated.-Construction:...
to empty into the bottom level of the canal. The process was quick and efficient, raising a tub boat in about four minutes, which was half the time required when the standby 16 hp steam engine
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...
had to be used.
Green took his inspiration for the methods of operating the planes from the work of Robert Fulton
Robert Fulton
Robert Fulton was an American engineer and inventor who is widely credited with developing the first commercially successful steamboat...
, but brought his own engineering skills to make a workable system.
The Grand Western Canal
Devon
Devon is a large county in southwestern England. The county is sometimes referred to as Devonshire, although the term is rarely used inside the county itself as the county has never been officially "shired", it often indicates a traditional or historical context.The county shares borders with...
section had been built as part of a proposed scheme to link the Bristol Channel
Bristol Channel
The Bristol Channel is a major inlet in the island of Great Britain, separating South Wales from Devon and Somerset in South West England. It extends from the lower estuary of the River Severn to the North Atlantic Ocean...
to Exeter
Exeter
Exeter is a historic city in Devon, England. It lies within the ceremonial county of Devon, of which it is the county town as well as the home of Devon County Council. Currently the administrative area has the status of a non-metropolitan district, and is therefore under the administration of the...
, but the scheme had foundered due to lack of finances, and the section near Tiverton was isolated, with the link to Taunton
Taunton
Taunton is the county town of Somerset, England. The town, including its suburbs, had an estimated population of 61,400 in 2001. It is the largest town in the shire county of Somerset....
never having been built. In 1829, Green again proposed a tub-boat canal with inclined planes, but by 1830, this had been altered to seven vertical boat lift
Boat lift
A boat lift, ship lift, or lift lock is a machine for transporting boats between water at two different elevations, and is an alternative to the canal lock and the canal inclined plane....
s and one inclined plane. Green acknowledged the ideas of Dr James Anderson of Edinburgh, who had proposed vertical boat lifts in 1796, but also noted that the proposals required interpretation in order to make them workable. Various prototypes had been built around the country, but none had proved successful.
There were delays in the commissioning of the boat lifts, as Green struggled with the engineering problems. The lift consisted of two chambers, each holding a caisson, which was joined to the other by chains which passed over a series of wheels. Since a boat displaces its own weight of water, a caisson with a boat in it balances one with no boat in it. In order to make the system work, the top caisson was filled with about 2 inches (5 cm) of water more than the bottom one, and motion was provided by the extra weight of water, which was about a ton. The difficulties arose when the descending caisson reached the water in the bottom chamber. Anderson had suggested that the water level should be lower than the level of the canal, so that the caisson could sink low enough for the boat to float out. Green had not implemented this, and ultimately the problem was solved by constructing what amounted to a lock at the bottom, so that the boat floated out into the lock and descended the last 3 ft (0.9 m) as it would in a conventional lock.
The inclined plane was more problematical. Green seems to have made an error in calculation, which resulted in the buckets being much too small. On the Bude Canal, he had used a 15 ton bucket to raise a five ton boat. Here he had designed a 10 ton bucket, and the loaded boats weighed about 8 tons. Commissioning tests indicated that a bucket capable of holding 25 tons of water would be needed, but the shafts were not big enough. The novel power source had to be abandoned, to be replaced by a steam engine
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...
. Green was dismissed in January 1836.
The Kidwelly and Llanelly Canal
Green was also involved in the extension of the Kidwelly and Llanelly Canal from 1833. Once again, he advocated a tub-boat canal, this time with three inclined planes: two twin-track inclines, which were counter-balanced, and a third, single-track incline, which required power. Ultimately, the power was supplied by a water wheelWater wheel
A water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power. A water wheel consists of a large wooden or metal wheel, with a number of blades or buckets arranged on the outside rim forming the driving surface...
, but Green had to admit that he could not complete the inclines, as he had underestimated the cost of their construction by a huge margin. He was dismissed from the project on 30 January 1836, just three days after his dismissal from the Grand Western project.
Final Days
The Grand Western and the Kidwelly and Llanelly Canal were the last canal projects that Green was involved in. He remained a prominent engineer, acting as a consultant for the Bristol DocksBristol Harbour
Bristol Harbour is the harbour in the city of Bristol, England. The harbour covers an area of . It has existed since the 13th century but was developed into its current form in the early 19th century by installing lock gates on a tidal stretch of the River Avon in the centre of the city and...
and the Newport Docks
Newport Docks
Newport Docks is the collective name for a series of docks in the city of Newport, South Wales.-Background:Newport was a small fishing port and market town until the coming of the industrial age at the beginning of the 19th century...
, and working on the South Devon Railway
South Devon Railway
South Devon Railway could mean:* South Devon Railway Company - the company that built the railway from Exeter to Plymouth* South Devon Railway Trust - the heritage railway from Totnes to BuckfastleighOther heritage railways in South Devon include:...
. He remained responsible for hundreds of structures in Devon until he was 60, and died, aged 68, in 1849. At the time of his death his son Joseph D. Green was resident engineer at Bristol docks.
Green had a prodigious workload for much of his career as an engineer, and it is not surprising that some mistakes were made. Nevertheless he made a huge contribution to civil engineering in South West England
South West England
South West England is one of the regions of England defined by the Government of the United Kingdom for statistical and other purposes. It is the largest such region in area, covering and comprising Bristol, Gloucestershire, Somerset, Dorset, Wiltshire, Devon, Cornwall and the Isles of Scilly. ...
.
See also
- Canals of the United KingdomCanals of the United KingdomThe canals of the United Kingdom are a major part of the network of inland waterways in the United Kingdom. They have a colourful history, from use for irrigation and transport, through becoming the focus of the Industrial Revolution, to today's role for recreational boating...
- History of the British canal systemHistory of the British canal systemThe British canal system of water transport played a vital role in the United Kingdom's Industrial Revolution at a time when roads were only just emerging from the medieval mud and long trains of pack horses were the only means of "mass" transit by road of raw materials and finished products The...