Upon their tops spun gigantic wheels.

Out of the centers of these wheels shot the radiant lances, hosts of spears of intensest violet light.

The radiance they volleyed was not continuous; it was broken, so that the javelin rays shot out in rhythmic flights, each flying fast upon the shafts of the others.
It was their impact that sent forth the thunderous drumming.

They struck and splintered against the walls, dropping from them in great gouts of molten flame.

It was as though before they broke they pierced the wall, the Monster's side, bled fire.
With the crashing of broadsides of massed batteries the sledges smashed down upon the bristling attackers.