"We're falling!" I gripped him. "Get below. Come with us."

But he jerked away from me. "Falling?"

A steward came running. "Falling? My God!"

Snap swung at them. "Get ahead of us! The manual controls—our only chance—we need all you men at the compressor pumps!"

But it was instinct to try and get on deck, as though here below we were rats caught in a trap. The men tore away from us and ran. Their shouts of panic resounded through the dim, blue lit corridors.

Coniston came lurching from the control room. "I say—falling! Haljan, my God, look!"

Hahn was sprawled at the gravity plate switchboard. Sprawled, head down. Dead. Killed? Or a suicide?

I bent over him. His hands gripped the main switch. He had ripped it loose. And his left hand had reached and broken the fragile line of tubes that intensified the current of the pneumatic plate-shifters. A suicide? With his last frenzy, determined to kill us all? Why?

Then I saw that Hahn had been killed! Not a suicide! In his hand he gripped a small segment of black fabric, a piece torn from an invisible cloak!

Snap was rigging the hand compressors. If he could get the pressure back in the tanks....