[CHAPTER VI]
LONDON BRIDGE
We come next to the consideration of the bridge. It is not a little remarkable that of the three great buildings belonging to Roman London—Citadel, Wall, and Bridge—not one should be so much as mentioned, save incidentally. One would think that the building of a bridge across a broad tidal river was an engineering feat worthy of admiration and of record. It was not so; we merely discover that a bridge existed; we are not told when it was erected, or what kind of bridge it was. Although it is certain that the people of southern Britannia possessed many arts and carried on commerce and lived with some show of civilisation—“people,” it has been remarked, “who possess mints and coin money do not live in huts of wattle and daub,”—yet there is nothing to show that they could build bridges. The Romans could and did. The names of stations in Britain show that they bridged many rivers—Pontes, Ad Pontium, Tripontium, Pons Ælii, for instance. The date of the construction of the first bridge across the Thames is nowhere recorded. We have seen that it has been hastily conjectured from a passage in Dion Cassius that a bridge existed over the Thames at the time of the invasion of Aulus Plautius.
We have already considered this passage. It may be permitted in addition to remark: (1) That the author had evidently an imperfect acquaintance with the topography, or he would not have spoken of the mouth of the Thames being so near London. (2) That he had heard the country described, very justly, as marshes. (3) That the marshes extended the whole way from Richmond to Tilbury. (4) That there could not have been a bridge across a tidal river of sufficient breadth for the whole of this distance. Whatever was existing in London at that time, whether the copia mercatorum mentioned by the Roman historian was really found there, or whether there was a ferry across, it is certain that the people frequenting London could not build bridges except of the elementary kind made of flat stones, such as are found over the narrow and shallow streams of Dartmoor. Guest considers that the marshes were those of the river Lea in the east of London; and certainly they are broad enough to bring an enemy into trouble; and higher up the stream is narrow enough for a bridge of rude construction. He says:—
“When the Romans came down the Watling Street to the neighbourhood of London, they saw before them a wide expanse of marsh and mudbank, which twice every day assumed the character of an estuary, sufficiently large to excuse, if not to justify, the statement in Dio, that the river there emptied itself into the ocean. No dykes then retained the water within certain limits. One arm of the great wash stretched northwards, up the valley of the Lea, and the other westward, down the valley of the Thames. The individual character of the rivers was lost; the Romans saw only one sheet of water before them, and they gave it the name of the river which mainly contributed to form it. When they stated that they crossed the Thames, they merely meant that they crossed the northern arm of the great lake which spread out its waters before them, and on either hand.”
There are, however, certain considerations which point in a different direction. We have already seen that the chief highway of traffic, the only communication between the north and the south, lay along what was afterwards Watling Street; that it passed down the Edgware Road, along Park Lane, stopping short of the marsh which covered the Green Park as far as Thorney Island; that a ford, perhaps left uncovered at low tide, led over the marsh to the island; that on the other side of the island (which is Westminster) there was another ford across the river to the renewal of the road—at Stangate—on the south side. Formerly this was part of the high road; the pack-mules and the slaves crossed every day at low tide. The water, which is now confined between two perpendicular walls, was then distributed at high tide over the immense marsh which begins below Richmond and extends to the coasts of Essex. The embankment of the river for business purposes in the City and the building of the bridge deepened and scoured the channel, so that the ford only became available afterwards in dry seasons, though up to the time of Queen Elizabeth it was still fordable after a drought. This ford seems to answer all the requirements of the narrative; it is just the place where troops, ignorant of the way, would step aside into deep water and so fall into difficulties. It is also the place where the army, following the road, would arrive at the river.
In considering the early history of the City, we must remember not only the connection of Westminster with this ford, but also the great and important fact of the trade which was carried on up and down the road over Thorney, making the place a busy centre of traffic before there was a Port of London at all. Whether the Port of London existed when the Romans began their occupation has been questioned. To me it is quite plain that it did. If there was no Port of London, then the merchandise intended for all the country inland was taken by river to Thorney. This much is certain, that the Romans established themselves in a fort on the east of the Walbrook. The building of this fort could not be undertaken until the position of the place and the navigation of the river were well known, because all the stone must have been brought by water. We will suppose, then, that an ordinary camp occupied this site before the fort was built. If we now consult the map we observe that the position, though it guarded the river, was isolated with respect to the way of trade and to the way of war.
It was therefore imperative to acquire the means of communication with that way. Had the Romans been unable to acquire that communication, the Roman settlement overhanging Walbrook would never have been built. In other words, the situation demanded a bridge, and a bridge was built. The date of the first London bridge is that of the first Roman occupation of London, i.e. the period immediately following the massacre under Boadicea.
What kind of bridge was built? First, we must remember that to build a bridge of stone over a broad and deep tidal estuary was a work which had never yet been attempted anywhere in the Empire. Certainly among the people of London there were none who would venture to attempt so great a work, while I do not believe that the military engineers themselves would attempt it. Next, it was a work which would certainly take a great deal of time; later on, for instance, the first stone bridge took thirty years to accomplish. Thirdly, it would be a costly work.
The answer must be sought in the bridges built by the Romans in other places about the same time. Two of these especially may be chosen. They are (1) the bridge over the Rhine constructed by Julius Cæsar in ten days, and (2) the Roman bridge over the same river at Mayence, of which a model exists in the museum of that town.
There can be no doubt that this bridge at London was, to begin with, a wooden bridge. The reasons for this conclusion are, briefly, as follows:—