of cloud by day, red and black smoke, and pillars of fire by night.
Now we run it off in pipes, and burn it to heat the blast, and the
top is shut by a cone. You'll be interested in that cone."

"But every now and then," said Raut, "you get a burst of fire
and smoke up there."

"The cone's not fixed, it's hung by a chain from a lever, and
balanced by an equipoise. You shall see it nearer. Else, of
course, there'd be no way of getting fuel into the thing. Every
now and then the cone dips, and out comes the flare."

"I see," said Raut. He looked over his shoulder. "The moon
gets brighter," he said.

"Come along," said Horrocks abruptly, gripping his shoulder
again, and moving him suddenly towards the railway crossing. And
then came one of those swift incidents, vivid, but so rapid that
they leave one doubtful and reeling. Halfway across, Horrocks'
hand suddenly clenched upon him like a vice, and swung him backward
and through a half-turn, so that he looked up the line. And there
a chain of lamp-lit carriage-windows telescoped swiftly as it came
towards them, and the red and yellow lights of an engine grew
larger and larger, rushing down upon them. As he grasped what this
meant, he turned his face to Horrocks, and pushed with all
his strength against the arm that held him back between the rails.
The struggle did not last a moment. Just as certain as it was that
Horrocks held him there, so certain was it that he had been
violently lugged out of danger.