Blisters like thin leeches run lengthways across the soles of my feet. In the greyness of dawn Max kisses my toes and gives me three pairs of socks to put over them. We go outside into the stillness to the line of vehicles and quads. They’re all plugged obediently into heaters to keep the oil in their engines warm. Max takes my gloved right hand between his two mittened fat pats of hands, and massages and pulls at my thumb.

‘That’s your quad thumb.’ He sticks it out. ‘It kills, the ache in it, after you’ve been heading into the wind and the cold for a while. It has to stick out from the rest of your fingers and work hard to keep pressure on the throttle. As soon as the pressure’s off, the quad stops. It’s a safety device, in case you fall off. Some people wrap rubber bands around the handlebar to keep the throttle pressed down. It can be absolute agony after a while.’

We’re sneaking away to the baby seals and an iceberg clump. We need the quads to get to them. I’ve never ridden one. We’ve got two, thanks to Wesley. He looks after the vehicles on the station.

‘Mum’s the word,’ he says to us and smiles. ‘Now I know why you were that bloody excited about the chopper, Fin.’

Max gives me a patient quad lesson and then we’re off over the frozen ocean. I’m slow and jerky until I get the hang of the throttle. My thumb begins to ache. Max keeps on zooming back to me. I accelerate over cracks in the sea ice. I become almost airborne over one. There’s a sliver of still sea beneath me.

‘Don’t look down!’ laughs Max, shouting back to me.

Suddenly, we’re among the captured blue. We ride among snaking alleys of hollows and caves and sheer walls of ice rising high. We stop the quads. The low song of wind is ghostly and faint around us as it threads among the skyscraper ice. We remove our gloves. Hold our hands to a sheer cliff of ice. It’s deeply cold and runny wet, as if the iceberg’s leaking slow water from it.

I step back into a crack. It’s been split by the tide beneath it. I drop with a yelp to my groin. Under the rock-solid surface is slush. My boot slurries in it. Max yanks me swiftly and cleanly from it.

‘We’ve all done that, sweetheart.’

I laugh nervously. ‘Well, I don’t want to do it again.’

‘You rarely do, after you’ve been in once.’