Friday, 27 May 2011

Old Wearmouth Bridge (NZ397575)

  

It is difficult to believe that the River Wear at Sunderland was not bridged until the 1790s. Wearside’s growing wealth was, of course, based upon shipbuilding and the export of coal – and the tall-ships of the day needed lofty access to the river’s lower reaches. Any such bridge would have to arch high above the river, and stone – the commonly-used material of the day for such projects – would surely be too expensive for such an exercise. After all, the river valley was wide (250ft) and fairly deep at this point. But the need was becoming pressing by the end of the eighteenth century and something had to be done.

Sunderland’s current Wearmouth Bridge is familiar to us all nowadays, of course; but its predecessor, the extraordinary ‘Iron Bridge’, had an unlikely link with an internationally famous historical hero. Thomas Paine, author of the seminal The Rights of Man, is the chap in question. Paine’s writings would help shape the post-revolutionary development of both France and the United States in the 1780s and 90s, but he had many other interests, too – among them, inventing. And though it has been the cause of much controversy over the years, it seems that it was a design formed originally by Paine in 1787 for a bridge over the Schuylkill River in Pennsylvania which eventually found physical form over the dear old River Wear.

The story is complex and unclear, but it is now generally accepted that the original ‘Iron Bridge’ at Sunderland, built during 1793-96, was based, at least loosely, on Paine’s original ‘American’ model. For reasons of finance, it seems, the US scheme never came to fruition, the half-finished, British-built bridge, finding itself being shipped north by its Rotherham constructors to form the basis of Sunderland’s brand-new industrial wonder.

Local MPs, Rowland Burdon and Ralph Milbanke, were the driving forces behind the scheme. After much research, both wood and stone were discarded as possible building materials; then, somehow, Paine’s iron-bridge design seems to have risen to the top of the pile. The world’s first-ever such effort, the famous ‘Ironbridge’ at Coalbrookdale, had been completed as recently as 1779 – but this famous gap measured only half of that to be bridged at Sunderland. Nevertheless, Burdon, Milbanke and their team (including, notably, engineer Thomas Wilson) bravely went for it, and gave the Walker Ironworks in Rotherham the go-ahead to start (or, perhaps, continue) the manufacturing process.

In the meantime, huge abutments were raised on the north and south banks of the Wear (completed in 1795), then two enormous wooden scaffolds were erected in the river to take the weight of the iron arches during construction. Six iron ribs were swiftly lifted into place to form the skeleton of the bridge, after which a further year was spent on applying the finishing touches. The new erection, at the time justly considered one of the wonders of the world and built at a cost of some £30-40,000, was finally opened on 9th August 1796. It was the largest single-span iron bridge on the planet, and over 80,000 folk turned up to witness the occasion.

Linking Bishopwearmouth and Monkwearmouth in this way proved to be the making of Sunderland, which flourished thereafter. It was a magnificence piece of engineering and much lauded in its day; but its design was flawed. As early as 1805, repairs were deemed necessary when the heat of the sun caused the cross-tubes which held the ribs together to loosen. And so the remedial work continued, until, in 1857, the famous Robert Stephenson took it upon himself to oversee extensive restructuring. The bridge was stripped back to its bare ribs, new iron-work added, and the abutments were raised to straighten out the lop-sidedness of the structure and to iron out the bridge’s distinctive hump. The result was a neater, simpler affair and bore the inscription, in Latin, “Do not despair, have faith in God.” It was re-opened in March 1859.

The volume of traffic over the fine old structure, however, continued to escalate, until it was decided to replace the bridge completely in the 1920s. But that, as they say, is another story.

Note:

The illustration shows a somewhat stylised engraving of the original Wearmouth Bridge, depicted prior to Robert Stephenson’s alterations. In reality, the bridge was a little lower and more elongated.

 
[ the above article is a slightly abridged version of the article which first appeared in Volume 2 of Aspects of North-East History – see www.lulu.com/historymick ]





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