Sums, sums. How much mass had there been aboard the damn thing? Water; gas-giant atmosphere, highly pressurised. About four thousand cubic kilometres of water alone; four gigatonnes. Compress it, alter it, transmute it, convert it into the ultra dense exotic materials that comprised an engine capable of reaching out and down to the energy grid that underlay the universe and pushing against it . . . ample, ample, more than enough. It would take months, even years to build that sort of extra engine capacity ... or only days, if you’d spent, say, the last few decades preparing the ground.

Dear holy shit, if it was all engine even the superlifter wouldn’t be able to keep up with it. The average Plate class could sustain about one hundred and four kilolights more or less indefinitely; a good Range class, which was what the Yawning Angel had always been proud to count itself as, could easily beat that by forty kilolights. A Cliff class superlifter was ninety per cent engine; faster even than a Rapid Offensive Unit in short bursts. The Charitable View could hit two-twenty-one flat out, but that was only supposed to be for an hour or two at a time; that was chase speed, catch-up speed, not something it could maintain for long.

The figure the Yawning Angel was looking at was the thick end of two-thirty-three, if the Sleeper Service’s engineering space had been packed with engine too.

The Charitable View’s tone had already turned from one of amusement to amazement, then bewilderment. Now it was plain peevish. The Sleeper Service was topping the two-fifteen mark and showing no signs of slowing down. The superlifter would have to break away within minutes if it didn’t top-out soon. It asked for instructions.

The Yawning Angel, still accelerating for all its worth, determined to track and follow for as long as it could or until it was asked to give up the chase, told its offspring craft not to exceed its design parameters, not to risk damage.

The Sleeper Service went on accelerating. The superlifter Charitable View gave up the chase at two-twenty. It settled back to a less frenetic two hundred, dropping back all the time; even so it was still not a speed it could maintain for more than a few hours.

The Yawning Angel topped out at one forty-six.

The Sleeper Service finally hit cruise at around two-thirty-three and a half, disappearing ahead into the depths of galactic space. The superlifter reported this but sounded like it couldn’t believe it.

The Yawning Angel watched the other GSV race away into the everlasting night between the stars, a sense of hopelessness, of defeat, settling over it.