prototype natural stepper, but there were phobics on his mother’s side – those unable to step at all, such as his notorious uncle, whose name he’d taken. Rod himself was somewhere near typical. With a Stepper box, Rod could step maybe three or four times a minute, but he’d be hit by nausea each time, and needed treatments to control the reaction. Luckily for him, by the time he was trying to fulfil his boyhood dream of flying the twains – the great stepwise-bound freight-carrying airships – the anti-nausea drugs had reached a pinnacle of effectiveness, and steps coming every few seconds, or even faster, were manageable.
This self-medication went unremarked by Joshua. Although he did wonder if the modern treatments still turned your piss blue.
The cabin windows were big and generous, and as the ground opened up beneath him Joshua was able to see the scattered lights of Reboot, and the neighbouring farms and shepherds’ shelters. But they hadn’t risen far before the settlement was lost in the continent-spanning forest, a deep green-black sea on this moonless night. ‘Makes you think how few we are, on worlds like this, even after all these years. And after all the breeding we’ve done.’
Rod grunted. ‘To me and my buddies this is normal. A planet’s not supposed to glow in the dark.’ He stowed away the pharma kit. ‘So you ready?’
‘Let’s go.’
Rod tapped a corner of another of his glowing screens.
The first step was a faint jolt, like a bump in the road– and suddenly they were in a rainstorm – and out of it with the second step.
After that, worlds flapped past Joshua’s view, one after another, variations on a theme of black, with not a light to be seen on the ground below. From the beginning the stepping was faster than Joshua’s heartbeat, which was a little disconcerting, like too-fast music. But as the step rate increased the inevitable juddering sensation soon smoothed out, to be masked, in fact, by the faint vibrations of the smooth-running engines as the plane settled into its run, heading generally geographic west, towards the heart of the continent and the footprints of Wisconsin, even as the stepping continued.
‘Nice machine,’ Joshua said.
‘Sure. “Wicked.”’
‘I won’t ask how much you paid to use it. Or how you earned the money in the first place, living the way you do.’
‘I’m making my living my own way, which you know nothing about. Look, here I am for you, just as you asked. You wanted us to spend time. Fine. This ride is my gift to you, Dad. Happy birthday, OK? But why the hell are you doing this?’
‘Why the hell not? I’m fifty. I’ve spent my life wandering the Long Earth. Why not cross a hundred thousand worlds in a day? Why not mark it with a stunt like this, while I still can?’
‘I hate to tell you, but I’m pretty sure it’s not a speed record.’
Joshua shrugged. ‘I don’t care about comparisons. I never much cared what other people thought of me, as long as they left me alone.’
‘Well, maybe you should care, Dad. I mean, like Mom said, you could have marked your birthday with something which wouldn’t have involved you being out here all alone.’
‘Like what? A barbecue?’ Joshua looked at his son sideways. Rod’s face was softly illuminated by the glow of the control tablets. ‘Now you sound like your mother. Or your grandfather. Once Danwas going to be a twain driver. Now here’s Rod the comber, who knows it all.’
Rod replied irritably, ‘I wanted to fly twains when I was a little boy, for God’s sake. And I got to do it, for a while. But there aren’t the opportunities now – you know that.’
It was true enough. Twains still flew locally, especially across the more industrialized Low Earths, but the big Datum–Valhalla route, a ‘Long Mississippi’ that had spanned a million worlds with a bridge of trade and cultural exchange, had withered after the Datum Earth had been effectively knocked out by