CHAPTER 8
Grand Selector Flaccus hammered the notice onto the refectory door and strode away officiously. Lambs no more, the first-years gathered round to read it. Torbidda’s eyes dropped to the final condition: Designs to be submitted anonymously. Influence could get you into the Guild Halls, but the annual competition was to ensure that all Apprentice Candidates were engineers of genuine ability.
‘How come the second-years aren’t interested? They’re the only ones eligible.’
‘They read it last year,’ said Leto. ‘The challenge is always the same.’
That made sense; the commission that had brought Bernoulli to fame was the audacious one-span bridge that remained the city’s main entry point. There was nowhere to hide on a bridge. Designing one was the purest test of an engineer.
Torbidda and Leto were still discussing it when Agrippina sat down beside them. She tilted her head to the notice. ‘They say you’re an excellent draftsman.’
‘Not bad,’ said Torbidda. ‘What do you have in mind?’
‘I’m a better anatomist than an architect.’ She smiled in embarrassment. ‘Something lofty and grand, I suppose.’
‘That won’t get you noticed,’ said Leto. ‘That’s what you want, right?’
‘Who are you again?’ Agrippina said archly. ‘Oh yes, the Spinther boy. A mediocre engineer trading on his family name. Mind your own business.’ In the Halls’ hothouse rivalry, everyone kept abreast of their fellows’ talent.
‘Down, girl,’ said Torbidda. ‘Don’t be offended by her country manners, Leto.’
‘Oh, I’m not. I know my limitations. As do you, Signorina, otherwise you wouldn’t have asked Torbidda’s help.’
‘Torbidda’s help,’ she replied, then softened. ‘Oh all right, I’ll bite. How do I get noticed?’
‘Say you design a great bridge. What good is it? The last thing this city needs is another bridge.’
‘So?’
‘So I grew up in a legion camp, and a better bridge is exactly what the legions needs. Momentum’s the key thing in any campaign, but if you think Etruria is bad, look at a map of Europa: rivers, rivers and more rivers. You know what’s involved in building a pontoon bridge? Tying boats together, making it level so carts can cross, keeping it stable so the animals don’t take fright – all that fuss, and Madonna help you if a storm hits. And then you have to dismantle the bloody thing. Design a bridge with practical military application and they won’t just make you Candidate, they’ll throw you a Triumph.’
After a pause, Agrippina smiled. ‘Not a bad idea, Spinther. I’ll keep you close when I wear the red.’
Leto gave a courtly bow. ‘I should be honoured.’
Torbidda said, ‘Well then, for starters it’ll need to be quick to assemble and disassemble …’
For the next few days they met in Drawing Hall to discuss ideas; working closely for the first time with Agrippina, Torbidda at last understood what was meant by the old saw, ‘Sober as an Anatomist’. She was practical as sinew and bone, and got quickly to the nub of engineering problems. Working beside first-years lacking his grasp of Wave Theory, Torbidda was used to stopping to explain himself. Collaborating with someone with an understanding equal to his was novel and fun. Both had initially thought of a portable, pre-fabricated truss bridge, but they rejected it because of the lifting equipment needed – and because both felt that something more ingenious was required.
Agrippina finished outlining her new idea and said, ‘Got anything better?’
Torbidda shyly showed his sketches. The idea had struck him during Ballistics: the arches of a bridge could be drawn by the arced path of a disc skimming across water, the supporting pillars forming wherever the disc hits the water. A stable surface, say tightly bound logs, could be rapidly unrolled and fastened to the arches before the army marched over.
Agrippina studied the sketches for a long time. She looked up at last, and said flatly, ‘A bridge that makes itself.’
‘Exactly!’ Torbidda said excitedly, ‘and it can be swiftly dismantled when the last solider crosses. One could bridge any distance of water, simply by shooting the disc further and—’
‘Torbidda, Torbidda, even if that were possible,’ she cut him off, ‘we don’t have the ability to make something like this.’
‘We don’t have to build it. You’re just trying to get noticed.’
Agrippina made a face. ‘The Apprentices won’t be impressed with a clever design if the theory’s unsound.’
‘It’s sound. Remember the first week I was here you sent me to Flaccus’ office?’
‘You sure can hold a grudge.’
‘You’ve seen that egg on his desk? It was designed by Bernoulli’s grandson. They say he showed potential.’
Agrippina’s lip curled. ‘That burn-out—. Yes, I’ve seen the egg. It transmits a phased current that repels pseudonaiades – nothing special.’
‘No, but think about how it works: by inducing density in water. Take that a step further and you could create a temporary structure, like foundations. Why not? Everyday ice is just one type of water polymorph. There’s no reason that we couldn’t create a more stable crystal structure.’
Agrippina shook her head. ‘Ice is weak, but that’s precisely why it forms. Ice, rivers, bones; nature always finds the quickest way. At low temperatures, controlled conditions, your polymorph would hold for a few seconds, maybe, but in the real world, in running water with applied pressure, forget it. Military engineering isn’t the rarefied theory of the Guild Halls. It’s more like politics: the art of the possible.’
‘But—’
‘And, as for bridge itself,’ she continued, ‘well, it’s very elegant, but the ballistics idea is pure fancy; no cannon’s that accurate, that consistent. So you’re left with a bridge that has the same limitation as all “self-supporting” structures – it can’t support itself until it’s complete. A marching army doesn’t have time to build elaborate formwork. Aside from practicalities, considerations of speed rule it out.’
Torbidda disagreed, but he could tell Agrippina was getting frustrated so he turned back to her plan of a parabolic swing-bridge. It had two fulcrums – that was what made it original; once it swung to the other side of a river and the army had crossed, it could be detached from its first base and swung across, disassembled and packed up again. It required a rope-and-pulley system and it had a limited span, but it would obviously work and it could be quickly transported.
‘Well,’ Torbidda sighed, ‘it’s practical.’
Those with families to visit took advantage of the brief end-of-year break. Torbidda spent the time in the Drawing Hall. Agrippina had remained intent on her swing-bridge and he had drawn it up handsomely, but his original idea kept going round in his head. It was foolish to devote more time to it, but Agrippina’s lack of imagination irked and he wanted to prove her wrong. An idea with merit had merit; it was an intellectual problem, nothing more. Her dismissal of the ballistics aspect stemmed from poor understanding; much error could be eliminated with more precise cannons.
But her criticism of the foundations was sound. He decided they would work better if they grew up instead of down: the moment that the disc connected with the water surface, it would send a powerful signal down to the bedrock, which would form a seed crystal of super-cooled ice, which would prompt a phase-transition to a crystal lattice in the water around it. The problem was to prevent that nucleation from dissipating randomly. Agrippina’s words came back to him: Nature always finds the quickest way. The water through which the initial signalburst travelled would be affected by its passage, if only temporarily, so all that was required was to make this dissipate slowly. That done, the column of super-cooled water above the seed would be the path of least resistance. The whole process would happen quickly, making rows of ice-trees appear in the wake of the disc skipping over the water.
He got up to stretch his legs and looked at the strange warped reflections in the great mirrors. The evening sun made the wrought-iron leaves of the windows look autumnal and fragile. He thought of the year, the struggles, violence and cruelty and the lessons learned, and he admitted to himself something that he could no longer deny: his mother had not betrayed him. He had betrayed himself – and that betrayal had begun before he could walk, from the time his hands could manipulate tools: fixing broken things, improving and making queer machines, the babble of numbers that grew louder every year; the comical patterns in the footsteps of a lame neighbour, the guilty rhythm of the midnight doorknocker, the sombre ratio of coloured leaves falling among the dead ones. He was as far beyond the other Cadets as they were beyond other children. Problems that stumped them, he solved effortlessly; his destruction of Four had merely been the first example.
‘Knew I’d find you here.’
‘Spinther! What news?’
They embraced in the warm reflection of the mirrors. After Leto filled him in on city gossip, the Bocca della Verità’s latest slanders, and developments on the Europan front, they discussed their electives. Torbidda had decided on Architecture, believing the mother of all arts would bring him closest to Bernoulli. Leto chose Military Applications for the same reason. The dark star they revolved around had mastered all arts.
They looked at their reflections, which curved round the edges as if they repelled each other, seeing the distance travelled in a year. Torbidda was taller now, and though Leto’s uniform was newer they might have been doubles.
Leto ran his finger round the mirror’s rim, producing an ethereal wavering note. ‘Perfect.’
Torbidda looked closer, and his reflection became distended, a vision of himself as a man. ‘No, there’s a flaw in it – see? There. Likely the alloy cooled unevenly. It’s subtle, but it distorts the light. It wouldn’t have been apparent before it was polished.’
‘I still think it’s beautiful.’
Torbidda silently smiled. Leto could never be a Candidate. The mirror was a weapon; its function was not to be beautiful, its function was to kill.
‘Come on, or we’ll be late for the shearing.’
When he saw the new first-years assembled, naked and shivering, Torbidda could hardly believe that he had once been such a lamb. It was more than another life; it was another person. In truth, he had not survived; the excess had been ground and cut away, leaving a brute, uncuttable stone. The coming year must polish it.