“Come on!” His voice shook. “I’ve got a good grip. Slowly and steadily. Don’t do anything suddenly.”

There was nothing else to do. Very cautiously I transferred the weight of my body on to his shoulder, then transferred my finger grip to another ridge where I had a better hold.

“I’m heaving,” I panted. “Right?”

“Yeah,” Kerman said, and I felt him brace himself.

I heaved with my arms and shoulders and slid up and on to the floor of the crevice. I lay there, panting until Kerman’s head appeared above the ledge, then I crawled forward and pulled him up beside me. We flopped down, side by side, not saying anything.

After a while I got unsteadily to my feet.

“We’re having quite a night,” I said, leaning against the crevice wall.

Kerman squinted up at me.

“Yeah,” he said. “Will I get a medal for that?”

“I’ll buy you a drink instead,” I said, drew in a deep breath, dug my shoulders into the wall and got my feet up against the opposite wall. By pressing hard with my shoulders and feet I managed to maintain a sitting position between the two walls.