This was a decisive and most welcome but still insufficient improvement, it was felt, for it restricted the reach of these constructions to the height of a single tree and thus to the necessarily limited length of its trunk. Since the width of certain abysses inconveniently exceeded the size of the oldest oaks, a way of multiplying those dimensions was the next step. This was accomplished through the invention of pilings, designed to support a bridge over water. The piling was first perfected with heaps of rocks tumbled into rivers large or small, followed by stakes driven in a circle into this foundation to make a kind of caisson, itself then filled with boulders. Such supports, placed at intervals across a body of water, permitted folks to line up tree trunks to their heart’s content. Now that’s progress.
Sometimes, however, up in the colder northern regions, few trees were available. There people turned, for lack of wood, to stone slabs hewn as best they could, until they realized that this substitute material was in fact preferable, much more solid and durable, and put it to general use. But sometimes as well, in the torrid south, few stones were available amid all the sand, so bricks were invented and used first to build temples and palaces, ramparts and ziggurats, and then — quite naturally — bridges. Recourse to brick now offering increased stability and implying new methods of construction, people wound up inventing the arch, some seven thousand years before Gluck. The arch is certainly the best thing we came up with, the thing that would change everything, an invention with which we were by no means finished for there are a few others like that, along the lines of the wheel.
As the first suspension bridges were appearing, along with pontoon bridges made of sampans or barrels lined up and bound together, we began to refine our choice of materials depending on their range of qualities. In the wood department, obviously oak was admirably suited for substructures, alder made excellent posts, while cedar and cypress were best employed in surface construction. As for stone, since tuff had a tendency to disintegrate, travertine burned easily, and marble often had to be imported from far away, a great step was taken with the recourse to mortar. At that point the hardest part was done — and in large part by Rome, until its empire collapsed and the barbarians arrived who, not building anything, destroyed everything they could.
Around 1000 we returned to constructing major roadways, streets, and bridges, all undertaken by a monastic order anxious to rediscover and develop the art of Roman architects. These Bridgebuilding Brotherhoods1 did not, however, offer much in the way of technical innovation, beyond modifying the form of the arch, from the semicircle to the basket handle and on to voussoirs,2 while awaiting the Renaissance and the invention of the lattice girder — a structure with a long span composed of compressed elements under tension, a novelty that would also shake things up considerably. After which the serious and methodical leading lights of the Enlightenment would thoroughly reconsider all these acquisitions, before the dawn of a new age of metal.
Helped along by the Industrial Revolution, wood and stone gave way to cast iron. Yet cast iron, ironically, is fragile, tires quickly, and the whole thing ends up cracking, breaking, collapsing over precipices in one catastrophe after another, the worst tragedies in the entire history of bridges until we finally decided to invent steeclass="underline" robust, resistant, ductile steel. Then came the bright idea of mixing gravel, water, sand, and cement to create concrete, which is a lot less costly than everything else, hard as stone although just as fragile but which comes into its own when reinforced by steel, the two of them now inseparable from then on and voilà.
Thanks to these new materials we began to build new suspension bridges, as in the olden days, except that we dropped the ropes and lianas for helically wound cables or parallel strand cables, sheathed in nylon to avoid corrosion. Attached to pylons by these cables or by heavy rust-proof chains, these suspension bridges were in line to become the longest in the world, their load-bearing capacity allowing them to cross the deepest valleys, the widest estuaries, the mightiest rivers. And while folks were at it, for shorter spans, they thought up the cable-stayed bridge, on which a series of inclined cables supports the weight of the deck, running directly to the pylons in either the harp or the fan design.
At the same time, old models were rethought: cantilever bridges, drawbridges, footbridges and other viaducts and we didn’t stop until we’d perfected all that, as much as we could, on an Earth given to quaking a thousand times a day, as everyone knows.
•••
Having sketched out this first outline of his project and developed it as much as he could, alone in his room, Gluck felt the need to refine, illustrate, and clarify it by going to see these bridges in situ and while he was at it, to finally get out and about. That was three years ago, but for the moment, the rain has calmed down a tad just as he was leaving Spring Hill. Now he will follow the directional arrows that, via Brooksville and Clermont, will guide him to Orlando.
So this is not his first trip, and he has taken a lot of them since he decided to travel the world. These journeys, however, were not begun solely to take his mind off his bereavement: that kind of travel usually goes nowhere, beyond making you go around in circles, for the air’s no better far away, you don’t feel any freer or more in control or perkier there and there’s no end to it. It’s even a stretch to tell yourself that you’re somewhere far away: for a heady few minutes you see or think you see new things with a fresh eye yet it’s a trap, a misunderstanding, because it’s not so much a place you’re discovering as it is a name you’re visiting instead. You feel proud above all about inhabiting it, about tramping around the exotic syllables of this name rather than the panoramas of the place itself, which to be honest swiftly becomes a backwater like any other where you soon think of nothing but going back to the old one, home, when you know perfectly well besides that it’s no better there so in short — what was the point.
You should not bestir yourself, therefore, without a goal, an axis, a heading, an idée fixe, otherwise you’re better off staying inside your own place looking out. Well, since the only constant thread in Gluck’s ideas had always been bridges, it was the project of seeing them that had gotten him going. Bolstered by all his experience, having read all the books, he had therefore decided to visit the greatest possible number of these bridges existent in the world, ideally even all of them although that would be difficult. The bridges, but also of course everything around them and all they overlook: since the type and style of a bridge vary according to the nature of the obstacle it must traverse, the study of that obstacle and its surroundings ought always to be part of the exploration.