an unusually large mass of rocks was thrown out, and the column of fire and smoke ascended nearly to the hovering craft. A moment later came an explosion, louder than any that had preceeded. "We'd better be going up; hadn't we, Tom?" his chum asked.
"A little, yes, but not too far. I want to get as many near views as I can."
"Bless my overshoes!" gasped Mr. Damon, as he heard Tom say that. Then he sent some of the vapor from the generating machine into the gas bag, and the Flyer arose slightly.
Ned looked in the direction of the town, but could not see it, on account of the haze. Then he directed his attention to the terrifying sight below him.
"It's a good thing it isn't very near the city," he said to Tom, who was engaged in watching the automatic apparatus of the camera, to see when he would have to put in a fresh film. "It wouldn't take much of this sort of thing to destroy a big city. But I don't see any streams of burning lava, such as they always say come out of a volcano."
"It isn't time for that yet," replied Tom. "The lava comes out last, after the top layer of stones and ashes have been blown out. They are a sort of stopper to the volcano, I guess, like the cork
