Under her touch the rock crumbled, leaving the imprint of her fingers.

In one awful instant he felt the rock under his elbow crumble, and then he fell.

The rock, locally called "water biscuits", is hard in the water but crumbles if allowed to dry out.

She moved her left aim, and as she did, rock crumbled from under her.

Of course the rock crumbles because part of it has been taken away.

The rocks across the road were already crumbling under the impact of the grenades.

And then the rock crumbled beneath her, and Kira started to slip off.

Soil, rock, and dying forest crumbled and fell away.

They had gotten food and water through into the various shelters with thin hoses but rock was still crumbling in on their tunnel efforts.

The rock crumbled under the fine red beam.