"Look at the cable!" called Stanley.
We did so. It was moving, writhing away from us over the bottom as though abruptly given life of its own. Coil after coil disappeared into the further gloom.
At length the cable was straight. The ball moved again—was dragged a few feet along the rocky floor.
Something—possessed of incredibly vast power—had seized the end of the steel cable and was reeling us in as a fisherman reels in a trout!
Slowly, unsteadily, we slid along the ocean floor. Ahead of us appeared a jagged black wall—a cliff. There was a gloomy hole at its base. Toward this we were being dragged by whatever it was that had caught the end of the cable.
Helpless, we watched ourselves engulfed by the murky den. In the beam of the searchlight we saw that the submarine cavern extended on and on for an unguessable depth. The cable, taut with the strain, stretched ahead out of sight.
Time had been lost track of during that mysterious, ominous journey. It was recalled to us by the state of the air we were breathing.
The Professor removed his mouthpiece and cast the tube aside.
"You might as well stop pumping, Martin," he said quietly. "We're done. There's no more air in the flask."