Chapter Eight
Kevin had made his way back to the Mainland in a daze, guided over the causeway by Ricard. His head was swirling with thoughts and ideas on how to solve the engineering problems he was now just beginning to grasp. He made his way through the non-existent border formalities as enforced, for want of a better word, by the Mainland Guardians. He then half-heartedly waved farewell to Ricard, being at some subconscious level aware that he did not want either to confuse or embarrass the man by offering to shake his hand again.
He tracked down his car in the car park, climbed into the Volvo and made his way back to his flat on complete autopilot. The journey, which in reality must have taken several hours, seemed to pass in a flash. He parked up, managing to find a spot only a few steps from his residence, and got out. He felt uncomfortable and ached in several places; belatedly, he realised that he had probably not moved more than minimal amounts while driving the car, so that after his energetic morning walking the old bridge and causeways, all his joints had stiffened.
On arriving at his flat, he dumped his coat and baggage unceremoniously just inside the door, then dug out his laptop computer from its bag and slumped at his desk. He looked around at the room, collecting his thoughts.
Kevin owned a small mid-terrace ground floor flat in a South Manchester neighbourhood which until fairly recently had been very run down and even unsafe after dark, but was now well down the road towards gentrification. The building had been extensively refurbished by an energetic and reasonably imaginative developer, and now boasted a total of four rooms. The kitchen was small and well-equipped, but with a level of cleanliness and tidiness that suggested either obsessive housekeeping or, more accurately in Kevin’s case, an occasional and erratic approach to home cooking. The small but well-equipped bathroom was similarly uncluttered and the bedroom was just large enough for a double bed and a couple of wardrobes.
The living room was indeed where Kevin really lived. More of a study than a lounge, it had a large and comfortable sofa, a decent-sized desk set into the bay window, and a couple of occasional tables undecorated except for reading lamps. Apart from the window and door areas, the walls were entirely covered with bookcases, purchased in flat-pack form and now filled with an eclectic mixture of textbooks, technical journals, reference works, classic novels, crime thrillers and whodunits, collected over many years and ordered carefully on the shelves.
After a few moments staring into space, Kevin opened the lid of the computer and started making himself notes. He knew he would have to work these up into a more formal report for his management eventually. For now, though, he jotted down his thoughts and impressions, trying to get as much as possible written down while it was still fresh in his mind, together with the inferences he had drawn almost without conscious effort during the long drive back.
Firstly, Kevin reviewed and summarised what he knew of the design specifications for the New Bridge. It was to be wide enough for a single line of vehicles to pass in either direction, with space for a footpath on either side of the carriageway. The obvious conclusion was that the planners still expected many people to cross on foot, although the extra width would remove the bottleneck which wheeled vehicles suffered on the old bridge.
There was no need for central barriers, implying that they were not expecting high-speed traffic of any kind. There were no rail tracks or anything other than a smooth surface across the entire road deck. There was a requirement for railings on each side, running the entire length of the bridge. These were specified to be unusually high and strong, and therefore heavy, adding the weight and cost of the project. They did make it, Kevin realised, effectively impossible to get off the bridge by any means except at the ends.
Curiously, one of the concerns expressed during the meeting was that steel would be a major construction material for the New Bridge. Kevin had proposed that a conventional approach of steel and steel reinforced concrete should be used for the Mainland side. This caused a lot of debate, but he had insisted that the use of any other material would be hugely more expensive. He had found this all rather strange, especially given Bret’s remarks earlier about this material not being useful for reinforcement on the Island side of the Old Bridge.
He got up and paced the flat, suddenly feeling incredibly hungry. He realised that he had not eaten anything today apart from a snack breakfast on the road, and the hot chocolate on Lyndesfarne. Time to eat, Kevin thought, collecting his coat from the heap beside the door, and setting off down the street to the take-away Chinese restaurant on the corner.
On entering the shop, he was greeted from behind the counter in a familiar fashion by a teenage girl of obviously Chinese genetic background. She had a Manchester accent so thick that even Kevin, who had been resident in this area since he was a student, found it hard to interpret her words. This girl seemed to be behind the counter on all of Kevin’s irregular visits. Her parents, who worked almost unseen in the kitchen beyond, were first generation immigrants and, he suspected, uncomfortable speaking English. Kevin wondered what it would be like for a person visiting this country from Lyndesfarne, for whom not only the language and culture would be entirely alien, but also the functional behaviour of even the most mundane of everyday items around them.
He shook his head, and then studied the menu attached to the wall. The Chinese girl looked on disinterestedly, working hard on perfecting the “cool” pose affected by teenagers everywhere. Kevin made his choice, and ordered and paid for his food. The girl scurried off to convey his order; the sudden increase in cooking noises and the tantalising smells emerging from the kitchen confirmed its receipt.
After the usual few minutes hanging around, a Chinese man Kevin knew to be the girl’s father emerged clutching a plastic carrier bag containing several cartons already showing signs of leakage. Kevin took the bag, nodded his thanks to the chef, and walked rapidly back to his flat. He poured his sweet-and-sour chicken and rice into a bowl and attacked it ravenously with a fork – he had never bothered learning how to use chopsticks – before returning to his desk.
One of the more alarming pieces of information that Bret had conveyed during the morning’s conversations was that the Old Bridge had collapsed while it was being built. The implication was that the design had been finally got right by trial and error. Short of sabotage, which Kevin discounted immediately, the only other possibility was that the two worlds had moved relative to each other. This seemed unlikely, he thought, and the intermediate zone was obviously stable. The Old Bridge had now been in position for several hundred years, and showed no signs of movement or cracking. Nor did it show any signs of being repaired after any such damage; Kevin had carefully checked for this during his earlier inspection of the bridge.
The thought of trial and error design was anathema to Kevin, and indeed to any reasonable modern engineering approach. There would have to be a huge investment in time and money in the New Bridge, and it really did have to be right first time. As a matter of course, he would use computer modelling during the design of the bridge, or at least his half of it. This was the conventional approach for bridges of all sorts in Kevin's world.
He got up and stretched, suddenly feeling very tired, and wandered into the kitchen for a drink. The strongly flavoured Chinese food had made him thirsty, and he opened and drank from a bottle of mineral water from the fridge. In his by-now near somnambulant state, he wondered dimly how the complexities of bridge design would be handled on Lyndesfarne. Did they have anything like computers, he thought, or could they solve hard problems in some other way?
“I’ll worry about that tomorrow,” he said to himself.
Over the next few weeks, Kevin wrestled repeatedly with this and many other issues in the bridge design. He spent a considerable amount of time with Bret, as the two of them converged on a joint design for the project.
They had already concluded that in effect two bridges were required. On the Mainland side, the solution alr
eady envisaged by Kevin would be a cable-stay bridge, consisting of a single steel re-enforced concrete support tower with steel-reinforced concrete roadbed, and with high tensile steel support cables. Bret proposed a superficially similar approach, with a tower and roadway, although Kevin was completely confused about the “tension distribution sails” that Bret described to him.
The key problem that Kevin and Bret were trying to solve was how to link the technological and magical sections of the New Bridge and indeed develop a complete design for the bridge as a whole. They were under instruction to keep the true nature of the project from the bulk of the design teams on either side, and so this particular part of the solution they were forced to tackle almost unaided. As far as the rest of the teams were concerned, the bridge design for the opposite side was a mirror image of the one they were responsible for completing.
To join the two parts, Bret and Kevin considered building a physical model of the New Bridge, to ensure that it would work as they hoped. Ironically, the only place that such a model could actually behave correctly was right in the centre of the Old Bridge. To be realistic, it would have to be a very large construction, extending out of the overlap zone into the areas where the rules of just one world applied. It would therefore have to be many feet across. Kevin was not absolutely sure that the Old Bridge could stand the weight of such a model; Bret agreed and they reluctantly dropped the idea.
For the join, they had considered two kinds of approaches. The first was distinctly low-tech: use traditional building materials and architectures for the overlap zone, building the joining section in stone or even wood. Kevin’s engineering sensibilities were appalled at the thought of a primitive stone arch featuring in his solution. Besides, it would mean that the flat road bed which was supposed to aid the smooth flow of traffic would be disrupted. The use of wood was also fraught with difficulties. It needed a lot of maintenance, and the bracing structures which would be required would be awkward, even cumbersome, to construct.
The other approach involved the use of a laminate – a multi-layer sandwich of thin layers of materials from either world. There would need to be alternating layers of steel reinforced concrete and the self-amalgamating building material from Lyndesfarne. When Bret first started describing this material, Kevin was fascinated. He had asked what the material was, and Bret had answered with a polysyllabic word he completely failed to catch. Apparently, the phrase was translated as “Construction Stone”. It could be made almost weightless when manufactured, for ease of transport, but was quite weak in this state. When required, however, it could be transmuted irreversibly to a heavier and much stronger form, as well as seamlessly amalgamating with itself.
Kevin suggested that the layers would be constructed over a wooden scaffolding framework, with the layer of concrete first. He was fairly certain that the concrete would retain its shape even under the rules of Lyndesfarne, even if it was not very strong, and it would support the construction stone if it failed to amalgamate properly. Once both materials had reverted to their final state, almost any variation of the strength of the materials could be compensated for across the overlap zone.
As a matter of course, Kevin performed extensive simulations of the New Bridge, using the computers in the Manchester office. To do this, he had to engage the help of several of his colleagues in order to build the complex software models. These computer-based models accurately predicted the stresses and deformations under both normal and abnormal load conditions, including high winds and unusual traffic densities.
Privately, Kevin also carried out some simulations based on his best understanding of the Lyndesfarne view of physics and the properties of materials. He discovered that there appeared to be a coherent set of physical rules which operated in Lyndesfarne which were for some reason just different from those of the world where Kevin originated. He did this behind-the-scenes programming work – “skunk-works” was the phrase that he had heard used to describe this kind of activity – using his own laptop and only in the evenings. After all, he remarked to himself, I don’t have much else to do.
There was no need in the plan for him to worry about the Lyndesfarne part of the bridge. The results of obviously detailed calculations were made available to him by Bret and the Island design team, but he could not explain how these calculations had been carried out. He told no-one about his own computer models, not even Bret. It also allowed him to imagine that he had discovered something about the Lyndesfarne world that was not known about already.
Based on these two simulations, Kevin had finally built a model of the intermediate area – the zone where the rules of neither world were entirely to be relied upon, but where it seemed there was a smooth transition from the rules of one universe to the other. Although this simulated description was not as detailed as the other two computer models, it did allow him to speculate on what would happen in the overlap, and give him a high degree of confidence in the solution he and Bret were proposing.