Each night they heard long convoys of transports arriving, but it seemed they were always short of everything, and the quarter­masters shrugged their shoulders. ‘If I had it I would give it to you.’

Even Orugi lost his temper. ‘Throne above! How can we hold out without powercells?’

The orders for each day were for the Cadians to hold every inch of ground with their blood. As the Cadian lines were thinned and reduced, the gaps were filled out with fresh Rakallion and Drookian reinforcements.

Bit by bit the Imperials were forced to give ground under a relentless bombardment and repeated assaults. They pulled back, trench-line by trench-line, until, after three days of furious fighting, the Cadians were pulled back to hastily laid out defensive lines that ran roughly parallel to the rockcrete contours of the hexa­gonal fortress behind.

Cadian engineers had been preparing this line of defence ever since the traitors started landing. And the wheelhouse was one of the strongpoints.

It was where Ostanko’s First Company had managed to break into the generatoriums in the bowels of the island, and so take down the void shields, but the Adeptus Mechanicus repair teams had long since cleared away any traitor dead.

The ceremonial arch of the wheelhouse’s entrance displayed an aquila held aloft in the hands of two sober-looking Guardsmen in archaic Rakallion greatcoats. The doors had been removed, and now the archway stood open to the wind.

Minka inspected the rest of the building as her troops made themselves as comfortable as possible. Baine was frying slab, Karni was boiling up a pot of recaff and Asko had pooled all their lho and was rolling sticks with the paper he had left.

The wheelhouse had once powered a giant air-conveyor between the two islands, and while the massive wheels were still there, the steel cables had been cut and now the waist-thick ropes of plaited steel trailed out into no-man’s-land and down into the water.

The wheelhouse roof had been hit. It had partially caved in, as had the walls, but the more the place had been pounded the stronger it became, defensively.

Their orders were to hold ground and minimise casualties.

‘No counter-attacks,’ Sparker ordered. Minka hated passing that order on.

The Cadians looked crestfallen. ‘We just sit here? We’re not pushing back?’ Baine said.

‘You’re welcome to go yourself,’ she told him, ‘just don’t let anyone catch you.’

The traitors came in under cover of darkness. Minka was lying in a low dug-out, Allun next to her. He spotted them first and pointed. Minka saw the dark shapes scurrying forward.

Firing started immediately. Minka had scavenged a carbine, which she now slid into her shoulder and bent to fire. After an hour she had to slam in a fresh powercell.

Mortar rounds started to fall among them. One landed so close it showered them in flakboard and masonry debris.