The Long War

snow. The detail of the forest flickered – once a tremendous, evidently recent crater appeared right under the prow of the Zheng He , before being whipped away like a stage prop – and occasionally a world flared, or darkened, and Jacques knew that the ships’ systems would be recording yet another Joker.
    Chen joined them, and grasped the polished wooden rail that ran before the window. ‘You might want to hold on.’
    Behind them, the trolls began to sing ‘Eight Miles High’.
    The stepping rate increased. To Jacques the passage of the worlds was suddenly visually uncomfortable, as if a strobe light were flashing in his face at increasing frequency. He tried to focus on the position of the morning sun, which remained constant in the multiple skies, but masks of cloud flashed across its face, and the sky flickered white, grey, blue. They all grabbed the rail now, even Roberta. Jacques thought he heard a thrumming of engines, and he sensed the airships driving forward even as they stepped. He could see the silvery hulk of the Liu Yang flex, a mighty plastic fish swimming through the flickering light of world after world.
    Behind them, a crew member threw up.
    ‘It will pass,’ Yue-Sai said. ‘We have all been tested for a tendency to epilepsy, and the nausea medication has been carefully applied. The discomfort will pass in a moment . . .’
    Faster and faster the stepping came, faster and faster the weather systems flickered past their view. Jacques forced himself to keep watching, and focused on the rail in his hands, the vibrations of the ship’s engines transmitted through the floor under his feet.
    And then the flickering seemed to fade away, the worlds merging into a kind of continuous blur. The sun, paler than usual, hung in its patient station, in an apparently cloudless sky that took on a deep blue colour, like early twilight. The landscape below was misty and vague, the shapes of the hills grey and dim, littered with patches of forest that seemed to grow, shiver, pass away. The river that had been writhing jerkily across the landscape now spread out, as if flooding a wide band of ground with a silvery grey, and the ocean coast too became a broad blur, the boundary between land and sea uncertain.
    ‘We have passed the flicker fusion threshold,’ Roberta murmured.
    ‘Yes!’ Chen cried. ‘We are now travelling at our peak rate, an astounding fifty worlds per second – worlds passing faster than the refresh frames in a digital screen, faster than your eye can follow. At such a rate we could traverse the great treks of the first pioneers of the Long Earth in little more than half an hour. At such a rate, if we kept it up, we could traverse more than four million worlds per day .’
    Jacques asked, ‘But we’re moving laterally too, right? Why’s that?’
    ‘Continental drift,’ Roberta said immediately.
    Chen nodded approvingly. ‘Correct. On Datum Earth the continents drift with time. The rate is something like an inch per year. Thanks to those cumulative effects there is also some drift as you move stepwise. So we move laterally, the great engines working to keep us over the heart of the tectonic plate on which South China rides. Sooner that than get lost altogether.’ He winked at Jacques. ‘Our Chinese airship technology has, incidentally, also set airspeed records.’ He checked his watch. ‘Now if you will excuse me I have engineers who need praising, or calming down, or both. Duty calls . . .’
    Jacques noticed that the lower digits on the Earth counter mounted on the wall of the deck had become a blur, like the worlds they were tracking, while higher, grander, slower-changing digits marked the tremendous strides they were making, off into the unknown.
    The trolls, meanwhile, sang on.

42
    V IGNETTES FROM THE continuing mission of Captain Maggie Kauffman, as the summer wore on across the Long Earth:
    The voyage of the USS Benjamin Franklin progressed in a rather disorderly, zigzagging way. The colonists of the Long Earth didn’t organize themselves consciously, either geographically or stepwise, and yet a kind of organization was emerging nevertheless, Maggie noticed, with clusters of homesteads growing up in neighbouring worlds. Gerry Hemingway of Science was developing a mathematical model of this, of a percolation of mankind into the Long Earth which resulted in a distribution that he described as ‘on the edge of chaos’. Maggie, wearily, thought that summed it up