Though exhausted, she kept working. There was so much to do. By ten o'clock that night Tiaan knew that the new crystal had the same properties as the last three. Would it fail the same way? Her body felt all hot and cold, her arms twitchy. Such were the effects of working with hedrons, and they were not always benign. Artisans had been known to die at their benches, burnt black inside or their brains boiled in their heads. It was called anthracism and everyone lived in terror of it. Tiaan's head was throbbing. Time to stop.

Depressed and hungry, she blew out her lantern and trudged off through the labyrinth of the manufactory, with its hundreds of compartmentalised work spaces. Each was crammed with workers, mostly women, making the individual pieces of the clankers that were so vital to the war. Such colossal labour it was that in a year the manufactory, with its thousand workers, its tar-fired furnaces going non-stop, could turn out only twelve clankers. The enemy could destroy a clanker in a few minutes.

Tiaan's room was tiny, but at least she had one. Most of the workers slept in dormitories where privacy was unknown. She climbed into bed but could not stop thinking. The war was delicately poised; it could go either way. Or so they were told. The failure of a few clankers could lose an entire army, and that could lose the war. And everything depended on controllers and the hedrons that were the core of them, the only way a human mind could shape and focus the power of the field to control such a massive object as a clanker.

The lyrinx were more than the equal of humans, in every respect. Only clankers could make the difference. Without them, humanity was doomed… Tiaan slept badly and not for long. Her head was full of brilliant, chopped-up images – crystal dreams. She always had them after work. These ones were about dead soldiers all lying in a row, covered in sheets to conceal their horrible mutilation. Long before a weak autumnal sun skidded over the mountains to blink at the fog and furnace fume, she was back at her bench.