Steely determination: How Scottish engineers changed the world

There is much discussion about the new Forth crossing, paricularly about how much Scottish steel is to be used in its construction.

While the arguments rage over the origin of the actual material to be used, it shouldn’t be forgotten that Scotland has done more than simply provide iron and muscle for such large civil engineering projects.

Thomas Telford could arguably be called the father of modern engineering. Born in 1757 into a farming family in Dumfriesshire, he was apprenticed to a stonemason at the age of 14, and some of his work can still be seen at the bridge at Langholm crossing the River Esk.

In 1782, he moved to London where he met renowned architects Robert Adam and Sir Willaim Chambers. He helped in the building of additions to Somerset House, before moving to Portsmouth dockyard, specialising in building projects.

Five years later, he was given the opportunity to make his mark on the country when his patron, William Pulteney, secured him the post of Surveyor of Public Works in Shropshire.

In 1790 he designed a bridge carrying the London-Holyhead road over the River Severn at Montford, the first of some 40 bridges he built in Shropshire, including major crossings of the Severn at Buildwas, and Bridgnorth.

The bridge at Buildwas was Telford’s first iron bridge. Although influenced by Abraham Darby’s bridge at Ironbridge, Telford felt it was over-designed, and many of the component parts were poorly cast.

By contrast, his bridge was 30 ft wider in span and half the weight, although it now no longer exists. He was one of the first engineers to test his materials thoroughly before construction. As his engineering prowess grew, Telford was to return to this material repeatedly.

More bridges, aquaducts and canals helped raise Telford’s profile, until in 1801 he devised a masterplan to improve communications in the Highlands, a massive project that was to last some 20 years.

It included the building of the Caledonian Canal along the Great Glen and redesign of sections of the Crinan Canal, some 920 miles of new roads, more than a thousand new bridges (including the Craigellachie Bridge), numerous harbour improvements and 32 new churches.

Telford also undertook highway works in the Lowlands, including 184 miles of new roads and numerous bridges, ranging from a 112 ft span stone bridge across the Dee at Tongueland in Kirkcudbright to the 129 ft tall Cartland Crags bridge near Lanark and the Menai Bridge in Wales.

In 1820, Telford was appointed the first president of the recently-formed Institution of Civil Engineers, a post he held until his death in 1834.

The Scotish farming community seems an unlikely source for engineering genius, but Sir William Fairbairn, born in Kelso in 1789, forged a similar path to greatness as Telford.

Fairbairn showed an early talent for mechanical engineering and served as an apprentice millwright in Newcastle upon Tyne where he befriended George Stephenson. In 1817, he launched his mill-machinery business with James Lillie as Fairbairn and Lillie Engine Makers.

Fairbairn was a life-long learner and joined the Institution of Civil Engineers in 1830.

In the 1840s, when Robert Stephenson, the son of his youthful friend George, was trying to develop a way of crossing the Menai Strait, he was instrumental in ensuring the latest technology and designs were used.

Tube bridge designs ultimately proved far too costly a concept for widespread use owing to the sheer mass and cost of wrought iron needed. Fairbairn himself developed wrought iron trough bridges which used some of the ideas he had developed in the tubular bridge.

His innovation knew no bounds, and Fairbairn conducted some of the first serious studies of the effects of repeated loading of wrought and cast iron girders, showing that fracture could occur by crack growth from incipient defects, a problem now known as fatigue. He built large-scale testing apparatus for the studies, and was partly funded by the Board of Trade.

Another Scot, James Nasmyth, would also prove to be instrumental in this field.

The son of Edinburgh artist Alexander Nasmyth, James had a mechanical mind and in 1825, at the age of 17, he built his first steam engine.

After apprenticing as an engineer and draughtsman, Nasmyith opened the Bridgewater Foundry in Manchester in 1834 with his partner Holbrook Gaskell.

Up to 1843, Nasmyth, Gaskell & Co. concentrated on producing a wide range of machine tools in large numbers.

But the most important of the machines the firm made was the steam hammer.

In 1837 the Great Western Steam Company was experiencing many problems forging the paddle shaft of the SS Great Britain; when even the largest hammer was tilted to its full height its range was so small that if a really large piece of work were placed on the anvil, the hammer had no room to fall,

Nasmyth thought the matter over and seeing the obvious defects of the tilt-hammer (it delivered every blow with the same force) sketched out his idea for the first steam hammer, which could deliver blows of varying degrees of force.

Nasmyth’s design proved invaluable during the Industrial Revolution, and by 1856 a total of 490 hammers had been produced which were sold across Europe to Russia, India and even Australia.

In memory of his renowned contribution to the discipline of mechanical engineering, the Department of Mechanical Engineering building at Heriot-Watt University is called the James Nasmyth Building.

While we may now face a debate as to who will provide the steel for any bridges in Scotland, it’s safe to say, without Scots, may we not be building any bridges at all.