He tried to explain what had happened. Their ship had been hit by a beam of lased gravity waves, that had come from outside the Galaxy. It seemed that the Snowmen, the builders of the ’Flake, had been able to manipulate something humans called Mach’s principle. Mach, or Mar-que, it was a name all but lost in the Qax Extirpation.

Kapur said, ‘You are embedded in a universe of matter. That matter tugs at you with gravity fields - but the fields surround you uniformly; they are equal in all directions, isotropic and timeless. The Snowmen had a way of making the field . . . unequal.’

‘How?’

Kapur laughed uneasily. ‘We still don’t know. I guess you learn a lot in thirteen billion years.

‘It has taken twenty-two years for the Academies to figure out how to deal with the Snowflake. For deal with it we must, of course. Its stubborn, defiant existence is not a direct threat to us, but it is a challenge to the logic of our ideology.’ Now he smiled, remembering. ‘After our failed mission we corresponded, Mace and I. I followed Mace’s career with a certain pride. Do you think it’s getting hot?’

‘Sir—’

‘When I was assigned to this second assault on the Snowflake, Mace was seconded to accompany me. He had risen to lieutenant. It galled him to have to become a wetback.’

‘Sir. Lieutenant Mace is dead.’

Kapur drifted to a halt, and sighed. ‘Ah. Then knowing me did him little good in the end. What a pity it ends like this.’

Gently Mari pulled the broken body from Kapur’s back. Kapur didn’t resist; he drifted to the wall, running his fingers over its moist surface. Mari pulled the cloak off Mace’s inert body, but it had been used up by its efforts to keep Mace alive.

She was surprised to learn of a friendship between a straight-and-true Navy man and a domehead. And then Kapur had attempted to haul his friend along with him, even though it must have been obvious that Mace couldn’t survive - even though Kapur, as their passenger Academician, would have been in his rights to demand that the rest of them carry him along.

People always surprised you. Especially those without military training and the proper orientation. But then, she had never gotten to know any domeheads before, not before this disaster, today.

She shoved the body back the way they had come, up into the darkness. When she was done she was sweating. Maybe it was getting hotter in here, as they penetrated deeper into the core of the Spline. ‘It’s done, sir. Now we have to—’

There was a flash of light from deeper inside the tunnel. And now came a high-pitched, animal scream.

Mari shoved Kapur out of the way and hurled herself down the tunnel.