Ahead of us marched a rampart of coppery cliffs rising, like all these mountainous walls we had seen, into the immensities of haze.

Something long drifting in my subconsciousness turned to startled realization.

The speed of the shell was slackening! The aperture containing the ionizing mechanism was still open; I glanced within, The whirling ball of fire was not dimmed, but its coruscations, instead of pouring down through the cylinder, swirled and eddied and shot back as though trying to re-enter their source.
Rador nodded grimly.
"The Shadow takes its toll," he said.
We topped a rise--Larry gripped my arm.
"Look!" he cried, and pointed.

Far, far behind us, so far that the road was but a glistening thread, a score of shining points came speeding.
"Lugur and his men," said Rador.
"Can't you step on her ?" asked Larry.
"Step on her ?" repeated the green dwarf, puzzled.
"Give her more speed; push her," explained O'Keefe.
Rador looked about him.

The coppery ramparts were close, not more than three or four miles distant; in front of us the plain lifted in a long rolling swell, and up this the _corial_ essayed to go--with a terrifying lessening of speed.