He got out his tinder box--a miner is never without one--and lighted a precious bit of candle he carried in a division of it just for a moment, for he must not waste it.
The light revealed a vault without any window or other opening than the door.

It was very old and much neglected.

The mortar had vanished from between the stones, and it was half filled with a heap of all sorts of rubbish, beaten down in the middle, but looser at the sides; it sloped from the door to the foot of the opposite wall: evidently for a long time the vault had been left open, and every sort of refuse thrown into it.

A single minute served for the survey, so little was there to note.
Meantime, down in the angle between the back wall and the base of the heap Lina was scratching furiously with all the eighteen great strong claws of her mighty feet.
'Ah, ha!' said Curdie to himself, catching sight of her, 'if only they will leave us long enough to ourselves!' With that he ran to the door, to see if there was any fastening on the inside.

There was none: in all its long history it never had had one.
But a few blows of the right sort, now from the one, now from the other end of his mattock, were as good as any bolt, for they so ruined the lock that no key could ever turn in it again.