New Notes Celebrate Scotland's Bridges|
January 14, 2008
It was no mere scriptwriter's fancy the Capt. James T. Kirk's chief engineer on the S.S. Enterprise waxed prosaic in a Scottish brogue. The Scots have long enjoyed reputations as serious engineers whether of a mechanical or civil bent. And, it is highly appropriate that the backs of the entire new 2007 series Bank of Scotland issues pay homage to some of the more notable engineering achievements of the Land of the Mountain and the Flood.
From Brig o' Doon to Kessock
The new series starts with historic Brig o' Doon on the £5. This elegant, single arch, stone bridge was built back in the 14th century. It spans the Doon River near Alloway in South Ayrshire. The note's design also features that archetypal Scots poet, Rabbie Burns, who sang the bridge's praises in his epic poem "Tam O'Shanter."
Burns' claims a literary connection with the bank. In 1786 he penned his poetic social commentary "Lines on a Banknote" on the reverse of a Bank of Scotland one-guinea issue. Words from his original hand-written poem appear as an underprint on the new note's back.
Harry Potter fanatics will be delighted with the new £10 note. It shows the quarter-mile-long Glenfinnan Viaduct, part of the West Highland Railway line. At the time of its construction between 1897 and 1901, it was one of the largest concrete projects ever undertaken, standing over 100 feet at its highest point.
To the right of the viaduct on the £10 vignette is the tower at the head of Lock Shiel that commemorates the Jacobite rebellion of 1745. It was at Glenfinnan that Bonnie Prince Charlie launched his unsuccessful campaign to win back the Scottish throne.
The Forth Bridge on the new £20 will be instantly recognizable to many readers. It was built between 1883 and 1890 to carry the North British Railway 1-1/2 miles across the Firth of Forth from North to South Queensferry. Three iconic, 340-foot-high, cantilever towers bear the tracks 150 feet above the Forth. Over 50,000 tons of steel were used in its monumental construction that cost 57 lives.
A more recent structure, the Kessock Bridge, appears on the £100. This cable-stayed road bridge spans the Moray and Beauly Firths. Built between 1976 and 1982 its four towers support 64 spiral-strand steel cables. The design was deliberately chosen as best able to cope with not just savage seas and strong winds, but also earthquakes. The bridge straddles Scotland's massive Great Glen Fault.
But bridges are little more than ways across a gap. The back of the £20 features something very special - The Falkirk Wheel, the world's only rotating boat lift. It represents the culmination of several hundred years of Scots engineering genius.
The lift was built in the late 1990s as the centerpiece of a multi-million dollar millennium project to reconnect the Forth and Clyde Canal with the Union Canal. The aim was to restore a waterway that had once provided the principal commercial link between the cities of Glasgow and Edinburgh. When the canal system was superseded by railways prior to World War II, the entire waterway fell into disuse and decay. Parts were filled in and housing estates built upon the recovered land.
The two canals met at Falkirk where they were separated by a 115-foot difference in vertical height. The original solution was to link them via a flight of 11 locks over a distance of just under a mile. By 1933 the 11 locks had been dismantled and in-filled. The problem that British Waterways faced in the 1990s was how to re-establish the link. The Falkirk Wheel provided the prize-winning revolutionary solution.
Archimedes in Motion
The wheel lift consists of two diametrically opposed, water-filled caissons, each of which can contain up to 80,000 gallons and four 66-foot-long barges. When the lock gates close, the caissons rotate about a central axis such that when the gates re-open, the boats can sail out, having been moved 115 feet iivertically.
For those who have forgotten their high school physics, Archimedes insists that the mass of a boat displaces a proportional volume of water. Consequently, the total weight of each caisson will always be the same whether it is filled with just water or with 600 tons of barges. Both sides of the wheel are always in balance.
The upshot is that the entire 600-ton mass of water and steel requires the input of just 1.5 kilowatts to rotate it through 180 degrees in less than four minutes.
The 1,200 tons of steel used for the wheel was preassembled in Derbyshire to ensure the final fit would be glitch-free. It was then dismantled and transported in 35 truck loads to Falkirk in the summer of 2001 to be re-assembled.
To cope with the constantly changing immense stresses on the structure during rotation, all steel sections are bolted together with more than 15,000 bolts.
Cost of the Wheel was £17.5 million. It was opened May 24, 2002, by Queen Elizabeth II as part of her Golden Jubilee celebrations.
The Falkirk Wheel is a stunning piece of working sculpture. It combines both function and design. The arches over the aqueduct add drama. They form a complete circle with their reflection in the canal and generate the feeling of a entering a tunnel, an image clearly evoked in the design of the back of the new £20 note.
Remarkably, the upper canal ends literally in mid-air. Boat travelers speak of the sense of sailing off the edge into the spectacular Scottish scenery beyond.
The Wheel is a unique engineering project and a modern engineering wonder. Put it on your list of "Things To Do," for the next time you visit Bonnie Scotland. Try Web site www.thefalkirkwheel.co.uk a'fore ye go. And for those who are thinking of taking a turn, in 2006 it cost adults £8 and kids £4 for the ride.
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