A book of bridges

by Walter Shaw Sparrow

THE BRIDGE OVER THE MAIN AT WÜRZBURG IN BAVARIA (1474-1607)

Here is an old defensive bridge that does not resemble a common man-at-arms: in him there is a fine courtesy, as of a knight long used to the etiquette of tournaments; but yet the technical inspiration is rather inferior to that in his great rival, the Moselle Bridge at Coblentz, built in 1344, by the Elector Baudouin, and charmed with a mellow grace that imparts a rare distinction to the vigour of fourteen bold arches. The Moselle Bridge is 1100 ft. long, or ninety-five longer than London Bridge. There is but one fault, and this one fault belongs to the Middle Ages: the ten piers obstruct the river too much, and two or three of them might have been omitted without harm to any strategic consideration.

In the Middle Ages almost everything was looked at from the standpoints of attack and defence. Bridges as well as soldiers needed armour, so their gateways and towers were built in a military fashion, and at times curious traps were devised along the footways. For example, consult the “Pacata Hibernia,” and you will find an engraving of Askeaton Bridge, [112] with a sort of hangman’s trapdoor at each end of the footway. In 1586, or thereabouts, Askeaton Bridge had another peculiarity: a castle stood close to it on an island in the river; and between the castle and the bridge was a fortified platform with two gateways.

It happened often, in mediæval times, that one arch was a drawbridge. Take Old London Bridge as an example. One of her twenty arches—the thirteenth from the City end—was a toll-gate for merchant shipping, and a drawbridge to gap off enemies from the town. It served this latter purpose in 1553, when Sir Thomas Wyatt and his insurgents tried to enter London. Everybody knew which was the movable arch, because it was connected in all popular talk with the tower that rose beside it, a terrible and gruesome tower, for on its summit executioners displayed the heads of decapitated persons, who ranged from common bandits to the great Sir Thomas More.

Some defensive bridges in Old England had an important look as late as the reign of George III. This applies to the Welsh Bridge at Shrewsbury, which had a noble tower at the entrance that looked towards Wales. Perhaps it belonged to the reign of Edward I, as a statue of Llewellyn was placed over one of the arches. At the present time our fortified bridges are minor specimens. The “auld brig” over the Forth at Stirling, once “the key of the Highlands,” is the most interesting architecturally. He still retains a defensive gateway at each end, and his four arches, now closed to traffic, have a bold and pleasant rhythm. They date from the last years of the fourteenth century. From this century also Warkworth Bridge comes to us; it is a smaller structure, with a triangular recess at each side, projecting from the parapet into the central pier. The gate-tower is at some little distance from the abutment; it has a low and narrow archway under which carters swear unhopefully, believing that their wagons will stick fast. A person who was present on the occasion told M. J. J. Jusserand that a gipsy’s caravan, not long ago, was stopped at the tower on Warkworth Bridge, and waited there while the pavement was being hollowed out to make the passage deep enough for a safe journey.

The pier midstream is triangular, and almost as sharp as an arrow-head. This shape is very common in mediæval cutwaters, but it belongs to a technical routine which cannot be regarded as practical. Floods cannot eddy around the flat surfaces of a triangle; they are cut into waves that soon break with an increasing force against the piers and spandrils. On the other hand, when a cutwater is shaped like a Gothic drop arch, or like a tierce-point arch, it meets the current with a much bolder wedge of stone, whose curved sides are better playgrounds for water in spate. Cutwaters of this improved sort are uncommon in mediæval bridges, but some are to be found in French work of the Limousin.

Viollet-le-Duc was the first critic who called attention to this technical matter, and no pontist should fail to note how cutwaters are designed. For example, in a bird’s-eye view of the bridge at Avignon the buttressed piers jut out on each side beyond the narrow footway, looking like boats that support a long line of planks; and I have no doubt that Saint Bénézet had in mind this figure of boats when he planned his roadway over “the arrowy Rhône.” It is far from my wish to compare the little Warkworth Bridge with this French masterpiece, but let us note in its cutwaters a similar character.

Again, when you remember that Warkworth Bridge belongs to the fourteenth century, do you not expect to find in it the pointed vault, whose lighter grace is among the most beautiful things both in Eastern and in mediæval architecture? Yet the two ribbed arches are segments of circles. For many a generation Northern England has been famed for three things—a long-headed thrift, a discontent that is said to be a Radical in politics, and a stubborn hatred for any new knowledge that attacks the dull mimicry of customs. It is to Lancashire, for instance, that you must go if you wish to study in old packhorse bridges the retention of Romanesque forms. A considerable number are described popularly as Roman bridges, probably because they are found on the old pilgrim ways, which, after the Reformation, were scorned as Roman Catholic.