, a little bitterness in his tone.

"Ruth, I think I'm going to save you all." Cliff looked into the
girl's face for a moment. "Please stand back twenty-five yards," he
repeated.

Kay took Ruth by the arm and drew her back. The crowd moved back,
their pressure moving back the vast multitudes behind them. The vast
mob was almost packed into the quarter of the Golgotha; there was
scarcely room to move.

Kay saw Cliff press the lever.

* * * * *

Slowly the giant top began to whirl. Faster ... faster.... Now it was
revolving so fast that it had become totally invisible. But Cliff was
almost surrounded by the wall of jelly. Only his back could be seen,
and then space was narrowing fast.

Kay gripped Ruth's arm tightly. He held his breath. The crowd, of whom
only a small part knew what was taking place, was screaming with
terror as the mass of jelly on the other side pressed them inexorably
backward. And Cliff had almost vanished. Would the machine work? Was
it possible that the psenium emanations would succeed where the
Millikan rays, the W-ray had failed?

Then of a sudden the air grew dark as night. Kay began to sneeze. He
gasped for air. He was choking. He could see nothing, and he strained
Ruth to him convulsively, while the terrified multitudes behind him
set up a last wail of despair.

He could see nothing, and he stood with the ax ready for the onset of
the monsters, more terrible now, in their invisibility, than before.
Then of a sudden there sounded subterranean rumblings. The ground
seemed to open almost under Kay's feet.

He leaped back, dragging Ruth with him. Slowly the dust was settling,
the darkness lessening. A faint, luminous glow overhead revealed the
sun. Kay was aware that Cliff had swung the top, so that the psenium
rays were being brought to bear upon the second mass of the monsters
on the other side.

The sun vanished in appalling blackness. Again the dust-choked air was
almost unbreathable. The shrieks of the crowd died away in wheezing
gasps; and then a wilder clamor began.

"The earthquake! The earthquake!" a girl was shrilling. "God help us
all!"

Kay stood still, clutching Ruth tightly in his arms. He dared not
stir, for all the world seemed to be dissolving into chaos.

* * * * *

Slowly the dust began to settle again. Perhaps five minutes passed
before the sunbeams began to struggle through. A cloud of grey dust
s