cliffs, falling toward the three over successively steeper shelves of jutting rock.

Then it turned again, at right angles, and the three found themselves at the exit of a dark gorge, little more than thirty feet high, but both narrow and long. Here the stream was almost perfectly smooth, and the thin strip of land on each side of it was covered with low shrubs. They paused and looked dubiously into the canyon. It was singularly gloomy.

"There's plenty of cover, at least," Honath said in a low voice. "But almost anything could live in a place like that."

"Nothing very big could hide in it," Alaskon pointed out. "It should be safe. Anyhow it's the only way to go."

"All right. Let's go ahead, then. But keep your head down, and be ready to jump!"

Honath lost the other two by sight as soon as they crept into the dark shrubbery, but he could hear their cautious movements nearby. Nothing else in the gorge seemed to move at all, not even the water, which flowed without a ripple over an invisible bed. There was not even any wind, for which Honath was grateful, although he had begun to develop an immunity to the motionless ground beneath them.

After a few moments, Honath heard a low whistle. Creeping sidewise toward the source of the sound, he nearly bumped into Alaskon, who was crouched beneath a thickly-spreading magnolia. An instant later, Mathilda's face peered out of the dim greenery.

"Look," Alaskon whispered. "What do you make of this?"

'This' was a hollow in the sandy soil, about four feet across and rimmed with a low parapet of earth—evidently the same earth that had been scooped out of its center. Occupying most of it were three grey, ellipsoidal objects, smooth and featureless.

"Eggs," Mathild said wonderingly.

"Obviously. But look at the size of them! Whatever laid them must be gigantic. I think we're trespassing in something's private valley."

Mathild drew in her breath. Honath thought fast, as much to prevent panic in himself as in the girl. A sharp-edged stone lying nearby provided the answer. He seized it and struck.

The outer surface of the egg was leathery rather than brittle; it tore raggedly. Deliberately, Honath bent and put his mouth to the oozing surface.

It was excellent. The flavor was decidedly stronger than that of birds' eggs, but he was far too hungry to be squeamish. After a moment's amazement, Alaskon and Mathild attacked the other two ovoids with a will. It was the first really satisfying meal they had had in Hell. When they finally moved away from the devastated nest, Honath felt better than he had since the day he was arrested.

As they moved on down the gorge, they began again to hear the roar of water, though the stream looked as placid as ever. Here, too, they saw the first sign of active life in the valley: a flight of giant dragonflies skimming over the water. The insects took fright as soon as Honath showed himself, but quickly came back, their nearly non-existent brains already convinced that there had always been men in the valley.

The roar got louder very rapidly. When the three rounded the long, gentle turn which had cut off their view from the exit, the source of the roar came into view. It was a sheet of falling water as tall as the depth of the gorge itself, which came arcing out from between two pillars of basalt and fell to a roiling, frothing pool.

"This is as far as we go!" Alaskon said, shouting to make himself heard over the tumult. "We'll never be able to get up these walls!"

Stunned, Honath looked from side to side. What Alaskon had said was all too obviously true. The gorge evidently had begun life as a layer of soft, partly soluble stone in the cliffs, tilted upright by some volcanic upheaval, and then worn completely away by the rushing stream. Both cliff faces were of the harder rock, and were sheer and as smooth as if they had been polished by hand. Here and there a network of tough vines had begun to climb them, but nowhere did such a network even come close to reaching the top.

Honath turned and looked once more at the great arc of water and spray. If there were only some way to prevent their being forced to retrace their steps—