The eurypterid soldiers march into battle like scuttling tanks, weapons mounted on their curving backs. Their heads are hooded with instruments, goggles over their stalked eyes like periscopes. Or else they control great machines that tear up the land with barbed legs or tracks, stopping every time they crest a rise to unleash a storm of fire or poison or sheer explosive force. They are in the air too, monstrous zeppelins raining murder upon the cowering peasants of the other side. They cruise the seas in segmented submarines that grapple with steel claws and tear each other apart. The warrior elite are no longer Those Who Fight, but Those Who Command. Everyone fights.

Should we visit this world now, however, that is not what we would see. Their Great War To End All Wars was fought and lost long ago, before our earliest ancestors came down from the trees.

But they are still there, those sentient descendants of sea scorpions. They live on the beaches, mostly. Most continental interiors are still too damaged for habitation—haunts of chemical weapons, radiation or plagues. The great hulks of their war machines lie rusting, and nobody is left in the world who recalls what they were.

The remaining eurypterids hunt what prey remains; they fish the oceans they didn’t taint with their long-ago war; they beat tools out of the wreckage of the past. And when one community meets another, they fight. Despite all that went before, they have not learned.

And who knows what happens next, because we cannot see the future. Who knows if they have a future, or if the whole cycle will start again, the most dismal repetition of history. Perhaps next time there will be no survivors at all.

4.

I

Alison had asked Julian over for dinner, which in practice meant him turning up with two bags of groceries and cooking for the pair of them. Alison herself bounced between the poles of greasy takeouts and salads so plain they’d make a diet plan wince. It wasn’t that she couldn’t cook but, postdivorce, she couldn’t be bothered with the fuss.

Josie was at one of her monthly writers’ groups and Julian had a minder in for John, along with an optimistic thought that he might be back first and thereby be clear of hard looks and awkward questions. When Alison called him, though, rather than him just turning up on spec, it meant she had something she needed to get off her chest. They were each other’s crutch, and he was aware that if work knew just how much they saw each other out of hours then eyebrows might be raised. It would be easier if Alison visited him occasionally, even though there seemed no real chance of Josie warming to her. Alison didn’t like getting out of the house much, though. And they couldn’t talk shop properly with Josie and John around. Or that’s what he told himself.