i
The making of the great Roman roads was the one great initiative in the story of English communications: it originated all that followed, and there was no new real development, no essentially new departure between the planning of that military scheme and the coming of the railway. It can only be compared to what the future may have to show if we find ourselves able to reform our roads as they should be reformed for the new conditions of modern travel, and even this change would not be anything like as great as the change made by the throwing of those great highways to stand for ever across a country which had hitherto been half barbarous.
[The Roman Road had a structure and character of its own] which it has retained to the present day, so that even where it was only the straightening and the strengthening of an old trackway upon which it was founded it would follow the mark of the Roman engineers throughout all that remained of its course. It was essentially a piece of building, and in this the Roman Road differed from every other form of communication before the modern railways. It had to be of this kind on account of two things which the Roman military engineers particularly desired to serve, both of them connected with the military character of the west. First, they wanted a platform, raised, as a rule, above the surrounding country, so that troops passing along it should be the less liable to attack: so that a view could be had from it over the immediate surroundings, which were cleared: and so that any sudden stroke against a marching column could be checked. The raising of the way had other objects, of course—it kept the surface dry, for instance—but the main object was that of security upon the march, and the same object was one of the reasons for making the roads as a rule in straight lengths or limbs, sometimes two, three, or even four days’ march in extent. A road was planned without windings, so as to be safer from ambush and surprise, and where it had coupled to its straightness its elevation above the surrounding country the chance of ambush or surprise was almost eliminated.
Part II, Sketch IV, The ROMAN ROAD SCHEME
But the habit the Roman military engineers had of driving their roads in these great straight limbs, which are still so clearly marked, served many other purposes besides this military one of which I speak. It has been condemned as a waste of effort, for it is clear that a winding road, avoiding steep gradients and turning difficulties of marsh or wood, requires less effort to construct, mile for mile, than an artificially straight one; and that even when you have allowed for the extra length of a winding road, the formula of least effort will never give you a long straight. But your straight road has the great advantage of rapid planning.
The Roman engineers, especially in the north—that is, in Belgium, Gaul, and in Britain—were working under campaign conditions, or in countries but recently occupied. They were under an imperative necessity of providing good communications as quickly as possible, and for that object the straight road was obviously the best. Once you had determined the two points which you had to join, you established a track between them and carried it over all but the worst obstacles, taking all but the worst gradients. If you met marsh, you built a causeway; whenever you came to a river crossing, you threw your bridge; when you came to a sharp, narrow ridge you made a cutting. All that meant labour, but as in any case you were intending to make a great built, constructed, raised structure along the whole trajectory the extra labour involved in a straight trace was not proportionally as heavy as it would be for one of our ephemeral modern roads. In other words, the Roman engineers set out upon a plan necessarily expensive. They set out to make a great public monument, as it were; and the extra expense of its straightness did not weigh in the bill.