Tarka and I joked last night that were it a prison cell, our tent would break almost every human rights contravention going. The floor space we share isn't much greater than the size of a pool table. There's barely enough headroom to kneel up (I'm typing this sat cross-legged and my head is about an inch from the top of our fabric ceiling). We have no running water, no lavatory (though we do share a pee bottle at night) and if we want electricity we have to go outside to tie a solar panel to the roof.

Of course, compared to the explorers of a century ago we are soft, spoilt pansies. We have things that would have made their eyes pop out of their heads, like Velcro and vitamin pills. But certain things they wrote about still ring true, and Apsley Cherry-Garrard, in his glorious polar masterpiece The Worst Journey in the World, talked of his colleagues' decency and kindness to one another, particularly when their living conditions became barely tolerable; how they never forgot to say "please" or "thank you".

We repacked our sledges before setting off this morning and I spotted that Tarka had taken the polar bear alarm (a heavy set of metal poles with a long cord and an astonishingly loud alarm that goes off if it's yanked) out of my sledge and stashed it in his, without saying a word. It was a small gesture, but one that summed up an awful lot about him, and about life out here.