The sound of welding-hot iron is unmistakable; almost a crackle, almost a smacking of lips, against a background of hissing. Ziani took the rake from someone's hand and gently opened a window in the roof of shining coals. Almost immediately a spark shot up, bright as a star, burst and went out. He could hear the hiss but not the crackle. The problem was the thickness of the staves. Welding thin pieces was easy enough, so long as you didn't let them get too hot and burn; but thick pieces like these had to be welding-hot all the way through, or else the seam would be weak and false. The biggest risk lay in waiting too long once the sparks began to fly, burning the outside while waiting for the inside to run. Then there was dirt, rust or scale in the seam, which would stop the edges merging into one piece-the flux was meant to guard against that, but if you waited too long the flux would burn away, scale would start to form. Pull the staves out too soon, before the melt started, and you could hammer as hard as you liked and nothing would happen. He felt the skin on his forehead burn, and his eyes were bleached from staring into the painful brightness of the fire, but he found he couldn't move away, not until the moment came…
(It was yes, then. He took it calmly, with resignation, putting the implications away at the back of his mind for later.)
Seven plump white sparks soared up out of the fire, and the crackle was like snapping twigs. "Now," he heard himself yell. He felt a hammer-shaft in the palm of his hand-someone must've put it there-as the two staves rose up from the glowing heap, white as the moon. As they moved through the air towards the mandrel, he noted dispassionately the slimy, wet look of the surfaces where the iron was softening into liquid. Everything was perfect as the staves slid gently on to the mandrel and the edges to be welded nudged together and touched, needing only his gentle strokes, his caress, to join them inseparably for ever.
I know how to do this, he thought as he lifted the hammer; not a prayer or an exhortation, a simple fact. He struck, and a shower of burning white stars, droplets of molten iron, shot up in front of his eyes like a fountain. He felt some of them on his cheeks, his wrists, the backs of his hands, melting his skin as he struck again, patting and squidging the wet staves together like a potter moulding clay. There were good smiths, excellent smiths, who never managed to learn the knack of the forge-weld, lacking the touch, the passion, the love. One blow slightly too hard would spring the joint before it had a chance to form; slightly too soft and the skin on the wet surfaces wouldn't burst and open up to each other. The sparks scattered and buzzed round him like furious bees, sweat flowed down his forehead and the bridge of his nose-one drop on the seam could ruin it, but he didn't dare wipe his face or move his head at all-while his arm rose and fell, his wrist delivering the delicate pecks, like kisses. People who believed in gods reckoned that a creator made the world. For a short while Ziani was prepared to believe in something like that; a god who gripped the Earth in mighty tongs, lifted it white hot out of the sun and joined its seams with careful, passionate taps, filling the night sky with sparks, somehow made sense; and whether he made it as a paradise for the righteous or a trap or a weapon had no bearing on the holiness of the moment when the edges fused into a seam, and the mountains sank hissing into the sea.
"Well?" Daurenja's chin was on his shoulder. "Has it taken?"
He didn't know; unbelievably, he wasn't even looking. "Too late now if it hasn't," he shouted back. "You'd better look for yourself, I can hardly see."
Which was true enough. He closed his eyes, but the all-consuming white glare was still there. "It looks fine," Daurenja yelled in his ear. "It's taken, we're all right."
Ziani opened his eyes, but he couldn't see anything. "Good," he said. "Now for the tricky bit. Get the mandrel in the fire, quick, before it takes cold."
The tricky bit; because to weld on the remaining five staves and close up the final seam, they had to keep the piece he'd just welded at or just under welding heat for the rest of the procedure; and that, as far as Ziani knew, was impossible. Someone was pouring water over his head and shoulders; someone else was binding strips of soaking wet cloth round his forearms. They'd lifted the two staves he'd already joined off the mandrel and nestled them back into the fire, a little further out towards the edge, while the next stave was buried deep in the heart of the coals, close to the mouths of the four air-tubes. His forehead was already dry again. Someone took the hammer from his hand and quenched it in the water-filled trench. It hissed, and a round ball of steam drifted upwards.
As he listened for the iron, he allowed his mind to wander. He tried to picture the City-the factory, his home, the Guild school, the house where he'd been born-but the light was too bright. So he searched in it for the faces of his wife and daughter, and found he couldn't quite form their shapes. They were two white pools, two pieces at welding heat, but however hard he tried (though the edges were clean as arrow blades and he was using blood as a flux), nothing he could do was quite enough to form a seam. Right at the heart of the fire was a cold spot. No matter how forcefully the bellows blew (they were piling on the charcoal, they were throwing on cartloads of sawn timber, wrecked wagons, smashed arrows, dead horses, dead men, whole cities, and each breath of the bellows bathed the fuel in white light and burned it away), still the cold spot was there, in his house, in her eyes, the night they came to search for the illegal mechanical doll. He could see it clearly now that the light had bleached his mind. He could see the door opening, the faces of strangers, a cold draught blowing into the warm house, lamplight on a halberd blade. I don't understand, she says; Ziani, what are they talking about, I don't understand. He understands, of course; he's guilty, he shares a truth with the strangers but not with his wife. He looks at her, sees fear and confusion and a refusal to believe, but something else as well, a cold spot. But it's a totally new procedure, an innovation, an abomination, and so he has no frame of reference, not until now, when he sees the same flaw in the white iron, and the two moments touch and weld…
He was hammering. The sparks lashed his face like rain, and he couldn't tell for certain whether the salt he could taste as he licked his lips was sweat or tears or just the last of the salt bacon. But somehow the cold spot had collapsed; he pecked at the growing seam and watched the shadow inside the translucent iron wince, as liquid metal flowed from one piece into another. "It's taken," Daurenja howled, and quietly, in the back of his mind, Ziani agreed. Not a thunderbolt or a sudden stab of understanding; it was more that, when he probed the thought, like a man with toothache feeling with his tongue, he knew that he could no longer believe in what he used to believe. The cold spot was still there, as thought cooled and it became too late to make it good.
It was her, the cold spot said. She told…
The hissing again, like the voices of other people who knew something he didn't. Sparks; he could smell his own hair burning. "Now," he called out without even needing to look; and they dragged out the two pieces; seven eighths of a cylinder, and the missing eighth stave. There were a dozen men straining on the tongs now, staggering under the weight of the blurred white shape as they slid it over the mandrel like a sleeve and Daurenja laid the eighth stave gently on top. Two seams to make in one heat, there wouldn't be time. He worked them alternately, hardly thinking about what he was doing, going by the feel of the soft iron under the hammer, since he could no longer see. His face was raw from the heat, even the hammer's wooden handle was too hot to grip. His throat and lungs were burning, he was drowning in heat and light, but all he could think about was the cold spot, the flaw in everything. It was her, she told them; in which case…