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The Early Pioneers – Bridges, Canals, Railways and Ships.�

Presented by Professor F.M. Burdekin FREng, FRS.�

On 24th October 2006�

Abstract�

The paper reviews the work of some of the engineering pioneers of the eighteenth and nineteenth centuries,�particularly comparing the achievements of Thomas Telford, George and Robert Stephenson and Marc and�Isambard Kingdom Brunel.�

The Background of World Events�

The second half of the eighteenth century and the whole of the nineteenth century were periods of great�change in the United Kingdom – the Industrial Revolution. Things were happening elsewhere in the world�as well. American Independence was declared in 1776 and the French Revolution took place between 1789�and 1799. England was at war with France between 1797 and 1815. The Crimean War took place between�1854 and 1856, the American Civil was from 1861 to 1865 and the Boer War from 1899 to 1902. Queen�Victoria reigned from 1837 to 1901 thus defining the true Victorian era.�

The British Engineers�

Prior to 1800 sources of motive power available were restricted to windmills, water wheels and low pressure�steam with a maximum power of about 50 horse power. Early steam power pre 1700 was limited to pump-�ing water. The development of the beam engine by Newcomen in 1712 led to a tier of pumps to lift 10 gal-�lons of water through a height of 153 feet. The principle of these forms of steam power was condensing low�pressure steam with a jet of cold water. Steam power was revolutionised by Watt in 1769 with a patent for a�beam engine with a separate condenser evacuated by an air pump. In 1800, Trevithick developed a double�acting high pressure steam engine for winding duties in Cornish mines and it was not until 1804 that the first�successful railway locomotive pulled a load of 10 tons over a distance of 10 miles. It was not until 1831 that�the principle of electromagnetic induction was demonstrated by Faraday.�

The era of major canal expansion in Britain was the second half of the eighteenth century and into the start�of the nineteenth century, driven by the need to transport coal and other goods in greater quantities and more�rapidly than had been possible previously. The key pioneering British Engineers involved in this were�James Brindley (1716 – 1772), John Smeaton (1724 – 1792), John Rennie (1761 – 1821), William Jessop�(1745 – 1814) and Thomas Telford (1757 – 1834). A major figure in the Manchester area, responsible for�the Manchester Ship Canal, was Edward Leader Williams. Telford also had a major influence in surveying�suitable routes for roads and arranging their construction for the London Holyhead route and throughout ma-�jor parts of Scotland.�

Railways began to become competitive from about 1825 and there was a tremendous expansion of railway�construction from the 1830s through to the end of the century. The railways became significantly faster than�the canals in delivering goods and also provided convenient means for passenger transport. The key pio-�neers in this were George Stephenson (1781 – 1848), his son Robert Stephenson (1803 – 1859), Isambard�Kingdom Brunel (1806 – 1859), Joseph Locke (1804 – 1860) and Thomas Brassey (1805 – 1870). Brassey�was the contractor who undertook many of the actual construction projects to build the railways. Brunel be-�came involved in the design and construction of very large ships in addition to his involvement in the rail-�ways.�

Canals, roads and railways all require the design and construction of bridges to provide suitable crossings.�Thus all of the engineers involved in designing the transport routes had also to design bridges.�

Basic Principles�

Canals involve channels of water and hence have to consist of series of essentially level stretches. The sim-�plest way to achieve this is for the canals to follow contours of equal height. Where the distances to achieve�this become too long or are impracticable, it may be possible to construct tunnels or cuttings to carry the ca-�nal through a hill or mountain, or aqueducts to carry the canal over a valley. If changes in level are neces-�sary, this is achieved though the use of locks in which the level within the lock is raised or lowered to match�the water level for the stretches of canal each side of the lock. It should be noted that it is necessary to ar-�range for a supply of water at different levels of a canal system to be able to top up water used in the locks�and to make up for losses.�

Although railways can operate over changes in level, such changes have to be gradual and steep gradients�must be avoided or the locomotive will not be able to pull its load up the slope and its driving wheels will�slip. It is also necessary to avoid sharp bends and changes in direction must be gradual. In a similar way to�canals, cuttings, tunnels and viaducts can be used to reduce the impact of changes in level. With railways, it�is essential that the rails themselves are well supported and fixed in position to maintain their spacing for the�wheels of the locomotive and carriages/wagons to run smoothly.�

The funding of the construction of both canals and railways was largely undertaken by private companies.�The driving force for the companies was the perceived opportunity to make money from charging for the use�of the completed asset. Each scheme required the approval of an Act of Parliament to permit the use of the�land for the proposed purpose – this was often contentious. The money was usually raised by investment by�shareholders – in the case of the railways £240 million. Most projects overran on both time and money!�

The actual construction of both canals and railways was undertaken by large groups of mobile construction�workers, known as navvies. For the London – Birmingham railway for example, 20,000 men shifted 25 mil-�lion cubic feet of earth in five years – enough to create a band of 3 ft width x 1 ft high around the earth’s�equator. A full days work involved a target for each navvy of shifting 20 tons of earth. The navvies lived in�temporary camps and had a reputation for getting drunk and fighting.�

Thomas Telford�

Thomas Telford was born in Eskdale, Scotland in 1757 as the son of a shepherd. He trained initially as a�stonemason but in 1782 he moved to London seeking work and worked on Somerset House. In 1787 he be-�came Surveyor of Public works for the County of Shropshire and became responsible for roads and canals in�the County. He became fascinated with the potential use of iron in bridges. An early example was Build-�was Bridge made of cast iron across the River Severn in 1796 (Figure 1). This bridge has been replaced�twice since that time because of ground movement. One of Telford’s most striking iron structures was the�Pontcysyllte Aqueduct carrying the Ellesmere/Llangollen Canal across the valley of the River Dee (Figure�2), built between 1795 and 1805 and still operating today, known as ‘The Ribbon in the Sky’. The canal is�carried in iron troughs on 19 cast iron arches of 45 feet (13.4 metres) span, supported on brick piers at a�height of up to 126 feet (38 metres) above the valley below.�

Telford showed his versatility in design of bridges with the Conwy and Menai suspension bridges, again�both still in existence although now bypassed to accommodate the much increased numbers and weights of�modern vehicles. Arch bridges have their main structural members in compression and hence cast iron was�suitable for these purposes, but for the critical tension elements of suspension bridges Telford had to move�to the more reliable wrought iron. The Menai Bridge was required to have a clearance height above the wa-�ter of 100 feet to allow tall ships to pass beneath. Telford’s design involved support by 16 massive chains�holding up a road length of 580 feet between the massive stone piers. Nothing approaching this scale had�been built previously. The bridge opened in 1826 and was part of the Shrewsbury to Holyhead road scheme�designed by Telford.�

After completing the Ellesmere canal, Telford moved back to Scotland where he completed the Caledonian�Canal and was responsible for development of some 1920 km of major road networks. Telford was respon-�

sible for specifying a very high quality of road manufacture involving carefully graded layers of compacted�stone of different sizes. This was more expensive that the alternative introduced by John Macadam which�used crushed stone coated with tar and did not require the same thickness layers, but Telford’s roads gave�excellent long lives. Whilst in Scotland Telford was responsible for the construction of many churches. He�also made regular visits to Sweden where he was responsible for the Gotha canal. He returned to Shropshire�in the final stages of his career where he was responsible for the Shropshire Union canal.�

Telford became one of the elder statesmen of the construction world and was elected the first President of�the Institution of Civil Engineers from 1820 until his death in 1834. He became known as the ‘Colossus of�Roads’ and was a truly great all round pioneer of engineering equally at home with roads, canals and bridges�using stone or iron as materials. He was elected a Fellow of the Royal Society in 1827.�

Figure 1 Buildwas Bridge Figure 2 Pontcysyllte Aqueduct�

The Stephensons�

George Stephenson was born in 1781. He was an inventive practical man but had little basic education. He�was responsible for development of improved miner’s safety lamps but became fascinated by steam engines�and railways. In 1823 he opened a locomotive factory in Newcastle in order to build the proposed Stockton�to Darlington railway which opened in 1825. George Stephenson was appointed Engineer to the Liverpool�to Manchester railway in 1824 and with his son Robert won the famous Rainhill trials with the Rocket loco-�motive in 1829. The Rainhill trials had criteria that the maximum weight of the locomotive was six tons on�six wheels and it was required to pull a load of 20 tons at a minimum speed of 10 mph with a steam pressure�not exceeding 50 psi. The five entrants were required to complete twenty runs of 1.5 miles length on level�track. Stephenson’s Rocket won with an average speed of 14 mph, and maximum speed of 30 mph. At the�time of subsequent trials in 1833, steam locomotives were shown to be capable of pulling 67 tons on the lev-�el, but could only pull 15 tons up a gradient of 1 in 100 and could not move up a gradient of 1 in 12.�

The Liverpool to Manchester railway created many challenges in the route to be taken in addition to the de-�sign of the locomotives. Two of the striking solutions were the construction of the Sankey Viaduct to the�North of Warrington (Figure 3) designed by Jesse Hartley, and the construction of the line over Chat Moss a�stretch of peat marsh. The original plan to drain the marsh failed. The solution adopted was to create a�floating bed of trunks, branches and brushwood, topped with soil, sand and cinders.�

George Stephenson was the founding President of the Institution of Mechanical Engineers in 1847. He died�in 1848 and was buried in Chesterfield, but was not elected to the Royal Society,�

Robert Stephenson was born in 1803 and from 1815 – 19 he attended Dr Bruce’s School in Newcastle, as�part of his father’s intent that his son would receive a better education than he had himself. In 1822 Robert�spent some time at Edinburgh University and then from 1824 to 1827 he went to Colombia. On his return,�he assisted his father with the Liverpool to Manchester railway project and was largely responsible for the�improvements to design incorporated into the steam locomotive ‘the Rocket’ that won the trials at Rainhill.�The success of the Rocket was due to the use of a multi-tube boiler with two inch diameter copper tubes to�

increase the heating surface area together with changing the inclination of the cylinders from vertical to an�angle of 350.�

One of Robert Stephenson’s major projects was the London to Birmingham railway for which he was ap-�pointed Engineer in 1833. This was a mammoth project, sometimes called the greatest public work of the�era, for the number of workmen (navvies) involved and for difficult civil engineering work, notably the Tun-�nels at Kilsby, Blisworth and Primrose Hill and the cutting at Tring. This railway cost £5.5 million com-�pared to a cost of £900,000 for the Liverpool to Manchester railway. He was also responsible for the�Chester to Holyhead railway from 1845 to 1850. A significant accident occurred with the bridge to carry the�railway over the River Dee at Chester when one of the cast iron girders broke as a train was passing and the�train fell through the bridge killing five people and causing many injuries. Stephenson had attempted to�strengthen the cast iron girders with wrought iron bars, but the post failure Royal Commission Report con-�cluded that the design was flawed and condemned use of trussed cast iron in railway bridges. The Chester�to Holyhead railway also involved the crossings of the River Conwy and the Menai Straits and Stephenson’s�novel design of wrought iron tubular box sections with the railway running inside was very successful and�applied to other projects elsewhere. The massive box girders for the Britannia Bridge at Menai were fabri-�cated alongside the straits and lifted into place by a progressive jacking operation. Advice and testing of�materials for these bridges were provided by contemporary leading engineers William Fairbairn and Eaton�Hodgkinson.�

Robert Stephenson was President of the Institution of Mechanical Engineers from 1849 to 1853 and was�elected a Fellow of the Royal Society in 1850. He was Conservative Member of Parliament for Whitby�from 1847 until his death in 1859.�

Figure 3 Sankey Railway Viaduct Figure 4 Lifting of the Menai Rail Bridge�

The Brunels�

Marc Isambard Brunel was born in France but emigrated from France to the USA in 1793 at the age of 24�under threats from the French Revolution. He came to Britain in 1799 and that same year married Sophie�Kingdom who he had met originally in Rouen. Their children were Sophia born 1802, Emma born 1804 and�Isambard Kingdom Brunel, born in 1806 in Portsmouth. Marc was a very inventive man and with the help�of Henry Maudslay produced a machine for making a new design of pulley blocks for naval applications.�He also did much in the development of saw mill machinery and for the mass production of soldiers’ boots.�The invention for which Marc Brunel is most often recognised is the ‘tunnel shield’ patented in 1818. This�device allowed workmen to operate safely removing soil underground behind and inside the shield, whilst�support for the part of the tunnel just completed was provided by brick rings immediately behind the shield.�On the basis of this device, Marc Brunel was commissioned in 1823 to build a tunnel under the River�Thames. The Thames Tunnel project was an extremely difficult one and met many problems. On one occa-�sion, the roof of the tunnel collapsed and the works were flooded with consequent injuries to a number of�the workers, including Isambard Kingdom Brunel. In the end, the Thames Tunnel at Rotherhithe was com-�pleted in 1843. Marc Brunel was elected to the Royal Society in 1814 and was knighted in 1841.�

Although Isambard had a basic education in mathematics and geometry from a very early age, his father be-�lieved that it was only in France that his son could receive a sufficiently advanced mathematical education�and so at the age of fourteen Isambard was sent to Caen College and then to Lycee Henri IV in Paris. His�father intended Isambard to go on to Ecole Polytechnique but he did not succeed in the intense competition�for entry and returned to England in 1822.�

Isambard threw himself into the Thames Tunnel project, eventually becoming Resident Engineer in 1827�and had to deal with the collapse and flooding of the tunnel on two occasions, one of which caused the�deaths of six workers with Brunel himself fortunate to escape although badly hurt. During his convales-�cence, Brunel spent time in Plymouth and in Clifton, Bristol. Whilst there in 1828 he learned of a competi-�tion to design a bridge across the gorge of the River Avon at Bristol. With the aid of his father, Isambard�put forward a series of designs for a suspension bridge with spans between 870 and 916 ft, but these were�rejected by the Committee on the advice of Thomas Telford that the maximum span should not exceed 600�ft. Telford himself put in a design involving two full height piers from the base of the gorge. Isambard put�in a modified proposal with a span of 630 ft not requiring piers and this was accepted by the Committee in�1831. In the end, the Clifton Suspension Bridge was not completed until 1864, after the death of Brunel and�used chains from another of Brunel’s bridge designs at Hungerford (Figure 5). Isambard Brunel was elected�a Fellow of the Royal Society in 1830 at the very early age of 24.�

One of Brunel’s major achievements was the construction of the Great Western Railway, eventually cover-�ing London to Bristol, Exeter, Milford Haven and Wolverhampton. This involved the design and construc-�tion of many major bridges as well as the basic track, stations and provision of locomotives and rolling�stock. Amongst the most striking of these, still in existence today, are the brickwork arch bridge across the�River Thames at Maidenhead (Figure 6), and the tubular iron Royal Albert Bridge across the River Tamar at�Saltash, Cornwall (Figure 7). The Maidenhead bridge has two flat elliptical arch spans, each of 128 ft, with�a central pier on a natural island in the river with four semi-circular arch land spans on each side. The river�spans have a height to the crown of only 24 ft 6 in., the shape being chosen to give clearance height for�masts of ships on the river without requiring a rise in level of the railway track across the bridge. Brunel’s�original design for the Saltash Bridge in 1845 was a series of timber trusses, but the Admiralty insisted on a�minimum clearance height of 100 ft. As a result, Brunel produced a new design in 1849 using a unique hy-�brid tied arch/suspension truss bridge with two main spans of 455 ft made of riveted wrought iron. The tu-�bular compression (arch) girders were elliptical tubes to improve lateral buckling stability whilst the tension�(suspension) members were chains made of links of flat wrought iron. The rail track is supported by hang-�ers from the tension chains and struts from the compression arches. The central pier was founded on mid�stream rock using a ‘Great Cylindrical’ caisson with a column of granite ashlar to a height of 96 ft above the�water. This was topped with four octagonal cast iron columns to support the ends of the main span girders�at mid stream. Many of the other bridges designed and built by Brunel for the Great Western Railway and�its extensions into Devon and South Wales were timber viaducts on masonry piers, all designed to carry a�double track railway of the broad gauge pioneered by him.�

Brunel’s other fascination was with extending transport from London by railway to cross the Atlantic Ocean�by ship to reach the United States of America. He was responsible for the design of the Great Western�(1838) as the first steamship to cross the Atlantic, the Great Britain (1845) as the first ocean steamship with�a screw propeller (Figure 8), and the Great Eastern (1858). The SS Great Western was a paddle steamer�with a wooden hull of 212 ft (65 metres) length, the SS Great Britain had an iron hull of length 320 ft (98�metres) and displacement 3550 tons converted to propeller drive during construction, whilst the SS Great�Eastern was a combined paddle/screw steamer of length 693 ft (211 metres) and displacement 22,500 tons.�The SS Great Eastern also had 5435 sq. metres of sail on six masts and five funnels (Figure 3). Although�the ship was responsible for laying the first TransAtlantic telegraph cable it was not a financial success and�was taken out of service in 1889.�

Figure 5 Clifton Bridge Figure 6 Maidenhead Bridge�

Figure 7 Saltash Bridge Figure 8 SS Great Britain�

Concluding Remarks - Comparisons and Competition between the Great Pioneers�

There was both rivalry and friendship amongst these great pioneers. Telford’s career largely pre-dated those�of the others and he was associated mainly with canals, roads and related bridges. However, as an elder�statesman, he was brought in as an adviser to the Liverpool – Manchester railway company on their concern�about the costs of George Stephenson’s design. He was also an adviser to the judging competition for the�Clifton suspension bridge and tried to have Brunel’s daring design rejected and replaced by his own more�conservative and more expensive design. The key to Telford’s successes was the ability to find and keep an�excellent team. He was meticulous and thorough and avoided conflict wherever possible. He was a superb�all round engineer.�

George Stephenson was original and innovative but not a good organiser - nevertheless he was an outstand-�ing engineer.�

Robert Stephenson, Isambard Kingdom Brunel and Joseph Locke were close contemporaries and rivals.�Stephenson and Brunel were the key figures in the ‘railway gauge’ battle where Brunel favoured the 7 ft�broad gauge to give more stability to the locomotives and rolling stock whilst Stephenson preferred the�‘standard gauge’ of 4 ft 8 inches which was eventually adopted throughout the country. Brunel supported�Stephenson when there were problems with lifting the huge box girders of the Britannia Bridge at the Menai�Straits and Stephenson supported Brunel when there were problems with the launching of the huge ship�Great Eastern. Both became seriously ill in their final years with chronic nephrytitis (Bright’s disease) and�they spent Christmas together in Egypt in 1858.�

Robert Stephenson was prepared to delegate but was pessimistic and easily discouraged. He was a humble�man but a brilliant engineer.�

Isambard Kingdom Brunel had boundless vitality and self confidence. He was an arrogant, ruthless perfec-�tionist who delegated to no-one but was an adventurous brilliant engineer.�

It is interesting to compare the final financial estates of this group of engineers. Telford left an estate of�£30,000, George Stephenson £140,000, Robert Stephenson £400,000 and I.K. Brunel £90,000. Brunel’s�estate was significantly affected by problems encountered with the construction of the huge ship Great East-�ern, where the dockyard went bankrupt and Brunel had to take over the final construction. By comparison,�Joseph Locke left an estate of £350,000 and Thomas Brassey, the contractor who actually constructed many�of the railways left £3,200,000.�

The achievements of the pioneers of engineering in the 19th century were truly astonishing.�