‘What the fuck was that?’ Polly managed, recovering her breath after landing on her back on the unforgiving ground.

Well, as about the nearest thing to an expert in temporal travel we have here, I have to say I haven’t a clue.

Polly looked around, then hugged her arms close around her body. ‘I thought it was your expert opinion that it was supposed to be warmer before that last ice age.’

Sorry, but there were more than one of them. You got a few in the Pleistocene age, but I thought you were beyond them, then some in the Carboniferous… Let’s just hope you’ve not gone that far yet. This is probably just some sort of hiccup: a bad winter, maybe a bad millennium. You’ve been covering millions of years, remember.

Polly tried not to think too much about that. Absentmindedly she opened her coat and removed from her hip bag a remaining lump of eohippus meat, and methodically devoured it.

‘Any idea at all what period this is?’ she asked.

None whatsoever. The thing that manifested around you might have altered the circumstances, and your previous time-jumps have been too out of kilter for me to easily work out a curve. I would guess you’re getting pretty near to dinosaur country, though.

Polly grunted an acknowledgement and continued eating as she stared about her. ‘Perhaps I’m just in the Arctic here—you said my position in space seems to be changing as well.’

I don’t think there was an Arctic, as we know it. I’m not sure, but I think that, in the region of time we should be entering, even the poles weren’t frozen over.

Polly nodded and started walking towards some nearby trees, since there she might find some shelter from the cold, and might even be able to get a fire going. At the forest edge she found it heavy going, as the snow had drifted thickly against boulders and fallen trunks. Eventually she reached a clearing and scanned the surrounding vegetation.

Looks like bamboo over there. That’s odd.

Polly immediately spotted what Nandru was referring to: the segmented trees spearing up like telegraph poles. Below these she discovered mounds of dry tendrils—light as balsa and only the thickness of her finger, segmented like the trunks they had dropped from. These fragments ignited easily and they burnt with a smell of pine. Polly was quickly able to build up a big fire, since it was apparent that every tree here was dead and their wood freeze-dried. It rapidly made the transition from campfire to bonfire: flames roaring up from the plentiful fuel. Polly sat on a nearby stump to soak up the heat. Scraping up handfuls of melting snow, she quenched her thirst. Then she noticed a strange regularity to the stump, and abruptly stood and stepped away. The fire’s heat continued to melt the snow and reveal what lay underneath it.

It was soon revealed as the head and forelimbs of some huge creature. The beaked head was covered by a large bony shield adorned with three lethal-looking horns.

Triceratops. Polly had seen enough films to recognize it.

‘I bet dinosaur meat tastes like chicken,’ she said, trying find some levity to quell the panic growing inside her.

Sixty-five million years.

Polly was appalled; she almost instinctively reached out to shift, and again found that glassy cage materializing around her. The shift this time was brief and the grey was suddenly displaced by a subliminal glimpse of burning jungle, furnace red, choking smoke and hot ash below a cyanosis sky. Intense heat washed over her, flames clawing in through the glassy structure around her, before she shifted again just to stay alive. Again jungle: cycads and tree ferns and horsetails, huge, strangely shaped trees which were mostly trunk and bole, with a minimal head of greenery. As the cage disappeared, smoke dissipated around her—having been transported through with her. She collapsed on her knees, coughing desperately.

It brought the atmosphere of that last place along with it. It’s almost as if the scale has conceded to your needs, so it can get on with its own journey without you fighting to control it.

That was not Polly’s most exigent concern at that moment.

You know, I think you just witnessed the dinosaur extinction.

Polly knew that. Her concern was that she was on the side of it she would rather not be.

Panicked by her discovery of the frozen triceratops, the girl shifted back beyond the vorpal sensor, and Silleck did not know if she survived the meteorite impact and firestorm that had preceded that killing winter and placed a full point at the end of the dinosaur aeons—that mercy killing of the diseased and dying populations of the great beasts. This, as Silleck knew, ended another of those long-drawn-out evolutionary wars between the large animals of Earth and their constant viral killers. Only humans had survived such a conflict, just.

Silleck now drew herself back down the aeons to where Sauros settled into the soft ground of the Jurassic. The city’s bones were still creaking, and the inner sphere had not yet turned to bring the floors level, but already Engineer Goron had abandoned his station to head for his customary place at the viewing windows. But the interface technicians remained where they were: Sauros, though slowly building up its energy reserves after such a journey, was still vulnerable to attack.

Silleck scanned the nearby slope, where the city was multiplied to infinity in all its incarnations, as if sitting between two facing mirrors. She scanned up and down time as far as she could without using sensors dropped in other ages, but there seemed no danger. Then she pushed her awareness downtime to a vorpal sensor often visited by her fellow technicians, to a brief period at the end of the Triassic and somewhat downslope, which had been named by them ‘the boneyard’.

Here there was some wrinkle in time that many torbearers missed. But it was a trap for many others, which killed their momentum should they fall into it. Thus they were caught for many days and without nutrition became the food for their own parasitic tors. Many of them were starving and half-dead when they arrived, and found no succour in this barren place. Silleck gazed down at the hot dry landscape, where human bones had been cleaned by grave beetles and small vulpine pterosaurs. She chose one scattering of bones and tracked it slowly back in time, seeing it reform, become fleshed and reinflate with moisture, and the brief instant when the tor reappeared enclosing the arm it had later torn away and disappeared with.

The man, who wore a turban and sarong, had walked for many days following a half-seen figure, before just giving up and sitting down to die. The figure, Silleck discovered, was an Australian aborigine, who survived and prospered in this arid hell, before being again taken away by his tor. There were other scatterings of bones, and other desiccated corpses. But it was all too grim, and the interface technician took herself back to one of the furthest sensors resting in the Permian epoch, where she knew another torbearer had been observed, but even as her awareness arrived in this sensor she began to pick up the waves of disturbance travelling uptime and upslope, through interspace, and knew that something was coming.

Gazing across the waves to where the plesiosaurs were mating — rolling in the sea, their great flukes arcing up fountains of water, their long necks slamming against the surface, and then rising and intertwining—Tack found he had acquired a deep and secure certainty about so many things. Foremost was the conviction that Cowl had to die, there was no question of that, and any of the wretched Umbrathane who got in his way should be eliminated as well. Raising his gaze to the dome enclosing the aquapark, and to the hard starlight beyond, he felt impatient to be on his way. At the sound of someone stepping onto the viewing deck behind him, he turned whip fast.