Then he, too, relaxed on the hard rock and sank into heavy sleep.
Of course a hard rock must be selected, such as granite or trap rock.
They put the flint on a hard rock and struck it with a heavy blow.
There was also a hard rock, not far from our lodgings, split through.
Slowly, with powerful blows, he bores a hole in the hard rock.
The ground now was hard rock, not ...