ut Marines, their own heads
might have been turned at the discovery of this sudden materialization
of a building out of nothingness.

Being Marines, they only grinned sheepishly, and followed along the
corridor.

* * * * *

The first human being they saw was one of the guards, in a black
tunic. He was leaning against a wall, and he was a human being no
longer. He looked as if he was asleep, but he was stone dead, with a
placid look on his face.

Two more dead guards lay across each other, with smiles on their
faces: and there was a workman in a blue blouse who had been in a
tremendous hurry to get somewhere, from his appearance, and had never
got there. He had fallen asleep instead, and never wakened.

Dick found a stairway and led the way up. He thought it ran up to the
laboratory, but, instead, the room into which he emerged was the
ante-room of the Invisible Emperor's audience hall. Six dead guards
lay in a heap in front of the curtain, and they had died as
unconcerned as their fellows, to judge by the pacific expressions on
their faces.

Dick passed through into the throne room. The Marines, behind him, for
the first time uttered exclamations of awe--of pity.

The terrific scene that met Dick's eyes would be burned into his brain
till his last day.

Upon his throne, head flung back, sat the Invisible Emperor, his
features set in a sardonic leer of death. And all about him, some
sitting, some lying, supporting one another, were his court, officers
in black uniforms with the silver braid, and women in court dress. And
all were dead too. But they had not known they had died. They had
fallen asleep--upon the instant that their own volatile gas reached
them.

* * * * *

"I guess that's the explanation, sir," said old Luke Evans. "Those
devils made the whirlwind and charged it with the gas. But when you
reversed that lever, you reversed the process. Instead of projecting
the force outwardly, you made a suction, and every atom of the gas
that hadn't travelled beyond the radius came rushing back and filled
the building. If we'd entered a half-hour later, we'd have been dead
ones ourselves, but the gas was volatile enough to disperse through
the chinks and crannies. Anyway, it's all over now."

Yes, it was all over, Dick thought, as he sat in his deck chair upon
the cruiser that was bearing him northward. The menace to world
government had been des