Suddenly Luca realised that he was only moments from being plunged into a wormhole mouth himself, and his heart hammered.

Blue-violet fire flared, and the yacht shuddered. Fragments of the Interface’s exotic matter framework were already hitting the yacht’s hull. That grey-gold sheet dissolved into fragments of light that fled from a vanishing point directly before him. This was radiation generated by the unravelling of stressed spacetime, deep in the throat of the flaw. For the first time since they had left Earth there was a genuine sensation of speed, of limitless, uncontrollable velocity, and the yacht seemed a fragile, vulnerable thing around him, a flower petal in a thunderstorm.

Luca gripped a rail. Aware of Teel at his side he tried not to cower, to hide his head from the stretched sky which poured down over him.

After a few days of hyperdrive hops and falls through branching wormholes, they reached the Orion Line. This was the innermost section of the Galactic spiral arm which contained Earth’s sun. They emerged at a new clustering of wormhole Interfaces, a huge interchange that dwarfed the port at Saturn, carrying the commerce of mankind across thousands of light years.

Here they transferred to a Spline, a living thing transformed into a Navy warship. In the increasingly dangerous regions into which they would now venture, such protection was necessary.

Before they resumed their journey to the centre they took dinner, just the three of them, in a transparent blister set on the Spline’s outer hull. At their small table they were served, not by automata but by humans, Navy ratings who hovered with cutlery, plates, dishes, even a kind of wine. It was a surreal experience for Luca, for all around the table, outside the blister’s glimmering walls, the Spline’s epidermis stretched away like the surface of a fleshy moon, and beyond its close horizon wormhole mouths glimmered like raindrops.

Commissary Dolo seemed slightly drunk. He was holding forth about the history of the Orion Line. ‘Do you know the geography of the Galaxy, Novice? Look over there.’ He pointed with his fork. ‘That’s the Sagittarius Arm, the next spiral arm in from ours. The Silver Ghosts strove for centuries to keep us out of those lanes of stars.’ He talked on about the epochal defeat of the Ghosts and the thunderous Expansion since, and how the great agencies of the Coalition, the Navy, the Commission, the Guards, the Academies and the rest, had worked together to achieve those victories - and how officials like the Surveyor of Revenues and the Auditor-General laboured to maintain the mighty economic machine that fuelled the endless war - and, of course, how his own department within the Commission, the Office of Doctrinal Responsibility, oversaw the rest. He made it sound as if the conquest of the Galaxy was an exercise in paperwork.

As the Commissary talked, when he thought Dolo wasn’t watching him, Luca studied Teel.