Next morning, when Spookie came downstairs, she found Puss purr-Miau getting ready to go. He gave her a hug and a kiss and said, “And now my dear, it’s time to say goodbye. You’ve been a splendid host, and I’ve thoroughly enjoyed my stay. But at long last I’ve found the missing piece in my puzzle, and I must be getting back to my hidden tomb in Egypt, and wait out the rest of time until I can present my report to Pharaoh.”
Spookie almost burst into tears. “You’re not going already, are you, Puss? Surely the end of the world is a long way off yet?”
“Oh no it isn’t. It’s sooner than you think. It’s just a little while before history begins all over again. The really boring bit is the 13.5 billion years I’ve got to wait until the reign of King Amasis (Life/Wealth/Health!) But I’m looking forward to them digging me up to ask me what I’ve found.”
“What have you found?”
Puss laughed. “Something so simple I can’t imagine how we time-cats have missed it the last eight times around. Our wizards have been separating uranium isotopes using fractional crystallisation, in great big square evaporation ponds in the Western Desert. It’s turning out to be a long slow business. But it’s so much quicker to cook uranium in a reactor until some of it turns to plutonium. Because plutonium is an entirely different element, so you can separate it out by simple chemistry. We Egyptians are good at chemistry. Did you know the word itself comes from Chemmis: the Black Land – another name for Egypt?”
Spookie did, as it happened. But she didn’t say anything. In fact she just stood there with her mouth hanging open, not able to utter a word.
Puss purr-Miau carried on explaining as if he hadn’t noticed.
“Plutonium is nasty stuff, but its critical mass is only a cupful. So that’s all you need to make a nuclear bomb. Whereas you need a barrowload of uranium 235. It would present us with real difficulties delivering that much uranium to Susa, the Persian capital, where King Cambyses lives. But it’s so easy to put a cupful of plutonium on the back of a camel and walk it there. So just let King Cambyses try any fancy stuff on us and there will be massive retaliation!”
He smiled. “One little thing before I go. Could you please change my batteries? I’d like a fresh set for this journey, seeing as it’s my ninth and last.”
Spookie found her voice again. “Yes–yes Puss, anything you say. But… aren’t you able to change the batteries yourself?”
“Sadly, no. When the old batteries are taken out, I simply stop dead and freeze solid. So I need someone else to do it for me.”
“Oh. Okay, I see.”
Spookie now moved with brisk determination. She went upstairs and got two new button cells. As soon she took out the old ones, the light in Puss’s eyes went out, and he became a statue once more. Spookie put the button cells on the mantelpiece, new ones as well as old, and stood deep in thought as she stared into the fire.
If Puss purr-Miau ever got back to Egypt and his hidden tomb, then Pharaoh would learn how to make a nuclear bomb to stop the Persians conquering the land. And Egypt would become a nuclear power. It would dominate the near-East indefinitely – maybe the world – maybe up to the present day. Recorded history would be all different. The Roman Empire would never have happened. There would have been no Europe as we know it – no England – and we’d all be walking around in Egyptian garb.
Worse still, she and Dyspepsia might not even get born. Come to think of it, the whole timeline of this alternative universe – just one of many – might not add up properly any longer, and the quantum space-time manifold might decohere into an utterly different universe.
All the stars would go out – pop! – the Earth itself would vanish, and Spookie and Dyspepsia would never have existed.
What had Puss said? It’s sooner than you think. He must have been talking about the end of the present timeline. Was he aware that it would all be his fault?
And yet… in herself she felt very much alive. At least, 51.05%, which was the best she ever managed. She could look out of the window and see stars. Dyspepsia had been born, and was presently in Egypt – only last night she’d spoken to her by FaceTime. Therefore Egypt had been conquered by King Cambyses, and Pharaoh hadn’t nuked the city of Susa.
All that might change, if she were to put new batteries in the Time Cat. So she didn’t. The ancient Greek who had written “do not put batteries in this cat” knew what he was on about.
Puss was now utterly immobile, and would stay that way if nobody put batteries in him. She gave him a little kiss, just below the ear, and stood him back by the fireside. Then she went upstairs and hid away the button cells, both old and new.
If you visit Spookie and Dyspepsia, you will see their lovely golden cat-statue standing by the fireside. Spookie keeps it well dusted and polished, and every now and then she gives it a sly kiss. She’s never going to part with it for as long as she lives. But she doesn’t know what’s going to happen when she and Dyspepsia are dead and gone. She can only hope that whoever owns the cat will obey the Greek instructions and not put batteries in it.
Because if they do, the Last of the Time Cats will come to life and go back to Egypt, and descend into his hidden tomb… and the world will end.