slowly up against the prop that upheld the roof.

He raised his keen knife.

She recoiled. The prop, none too strong, suddenly gave way under
her weight.

The whole roof of the chamber fell with a crash, earth and stone
overwhelming Elaine and her assailant.

. . . . . . .

By this time Joshua had left the house and had gone out into the
garden to get something to pry open the fireplace door.

Of a sudden, to his utter amazement, a few feet from him, it
seemed as if the very earth sank in his garden, leaving a yawning
chasm.

He looked, unable to make it out.

Before his very eyes a strange figure, the figure of Long Sin in
his oxygen helmet, appeared, struggling up, as if by magic from
the very earth, shaking the debris off himself, as a dog would
shake off the water after a plunge in a pond.

Long Sin was gone in a moment.

Then again the earth began to move. A paw appeared, then a sharp
black nose, and a moment later, Rusty, too, dug himself out.