As we fell I had heard his weapon rattle on the floor above, knocked from his grasp, but as we reached the well's floor he had already gripped us with a half-dozen pseudopod-arms that formed themselves lightning-like out of the shapeless mass of flesh that was his body. Then we were plunging about the floor of the well in a mad, weird battle, as silent as it was deadly.

The thing could not cry out for help, but for the moment it seemed to us that alone it might conquer us, its suddenly formed arms coiling swiftly about us, great tentacles of muscle that were like to have choked us in the first moment of combat. Strike and grasp as we would there seemed no vulnerable spot on the creature's slippery body, and weary as we were the outcome of the struggle was for a time extremely doubtful. I heard Sar Than utter a strangled cry as a thick arm noosed itself about his body, felt another striving for a hold on my own head, and then saw Jor Dahat suddenly grasp two of the slippery arms and literally tear the thing's shapeless body into half with those two holds. There was a soft ripping sound and then the creature had slumped to the floor, a limp mass of dead flesh.

A moment we stared breathlessly at each other over the dead thing, then without speaking sprang to the wall, where Jor Dahat braced himself to repeat our former procedure. In a moment he had raised the Arcturian above him, and within another moment Sar Than was raising me likewise until I had again gained a grip on the rim of the shaft above. A fierce struggling effort and I had pulled myself up to the floor of the dim-lit corridor, where I lay panting for a moment, then leapt to my feet and over to the recess in the wall from which I had seen the flexible ladder taken. A moment I pawed frantically in the recess, then uttered a sob as my fingers encountered the cold metal of the ladder. It was but the work of an instant to lower it into the well for my two companions to climb up, and then we gazed tensely about us.

The long, dim-lit corridor was quite empty for the moment, though away down its length we glimpsed the square of white light that marked the point where it debouched into the great caverns. That was our path, we knew; so down the corridor we ran, between the rows of those shaft-cells on either side, until we were just passing between the last two of those shafts and were reaching the point where the corridor narrowed once more. And then we suddenly stopped short, stood motionless; for, not a hundred yards ahead, a double file of the nebula guards had suddenly issued from a door in the corridor's wall, and were gliding straight down its length toward us!

V

For a single moment death stared us in the face, and we stood there stupefied with terror. As yet the guards approaching us seemed not to have glimpsed us, owing to the corridor's dim light, but with every moment they were drawing nearer and it was but a matter of seconds before we would be seen and slain. Then, before we had recovered from our stupefaction, Sar Than had jerked us sidewise toward one of the last shaft-cells in the floor that we had just passed.

"Down here!" he cried, pointing into its dark depths. "Down here until they pass!"

In a flash we saw that his idea was indeed our last chance, and at once lowered ourselves over the dark shaft's rim, hanging from its edge with hands gripped on that edge.

We had not been too soon; for a few seconds later there came the rustling sound of the guards passing above, gliding down the corridor past our place of concealment. As they glided by we hung in an agony of suspense, hoping against hope that they would not glimpse our hands on the pit's rim, or notice the absence of the creature left to guard us. There was a long, tense minute of waiting, and then they were past. We hung for a few moments longer, with aching muscles, then drew ourselves up to the corridor's floor once more and started down its length toward the square of white brilliance in the distance.

Down the dim-lit corridor we ran, past open doors in its walls through which we glimpsed great halls and branching passageways, all seeming for the moment deserted. A few moments later we had reached the corridor's end, and were peering out into the gigantic, white-lit space that lay beyond, a space alive and clamorous with the same multifarious activity as when we had come through it. To venture out into that great place of humming machines and thronging nebula-creatures was to court instant death, we knew, yet it must be crossed to gain the single shaft that led upward. Then, while we still hesitated, I uttered a whispered exclamation and pointed to something in the shadows beside us, something big and round that lay just inside the broad corridor's dusk, and that gleamed faintly in the dim light. In a moment we were beside it, and found it to be one of the great turtle-machines that swarmed across the floors of the vast caverns beyond us, though this one was unoccupied, its round door open to expose the hollow interior of the dome.