sworn, took on suddenly the form and substance of mocking speech: "Facilis decensus Averni," it whispered in his ear, as in a dim current of the whispering wind.
Marston had brought with him a ball of stout twine as a necessary precaution in threading the uncharted deeps of the underground corridors. This he had knotted firmly in a clove hitch (for Marston had been a sailor). There could have been no fear of its working loose, and less danger of its fraying out against the rough walls of the passageways, since at all times it would be loosely held. Like a thin snake, it spread itself behind them, and like a snake. . . .
The accident had been impossible to foresee. He had known that it could not happen; and yet. . . .
The Professor, leading the way with lantern held well aloft, had exclaimed aloud at the vivid beauty of a stalactite in his path, adjacent to a broad, deep ledge some three feet in height.
"Ah, Gerald!" he had cried. "It is alive—it writhes with motion—observe how it has grown, layer upon layer of smooth perfection! And the ledge—a perfect replica of an ancient sarcophagus! Look—"
But he was destined never to complete the speech.
For with the words he stumbled—a bight of the line snaked out to coil around his ankle—tottered, even as from behind him something moved, flashed, descended upon his head—something cold and hard. He fell, with a sodden crash, face downward in the mold.
And with his fall the lantern crashed to the floor of the cavern, sputtered a moment feebly in a brief spark of life, and then died abruptly. And at the feet of Marston that which had been sentient, alive, now lay still and motionless in the dust.
Marston stood for a moment, with groping fingers extended into the void about him; his head sang, his eyes blurred. The velvet black became suddenly, as it were, endowed with life and movement, mysterious, whispering. Near at hand there sounded abruptly a horrible, fetid panting—a gross intake of whistling breath which, in a sudden overmastering panic, he did not recognize as his own labored breathing.
"God!" he cried, insanely, and then, in panic-struck terror at the sound of his voice, fell silent and stood shivering like a frightened horse.
With fumbling fingers he felt in his pockets and produced a box of matches, finally, after many attempts, lighting one which he held tremblingly above his head. He did not glance at the figure at his feet, but over and beyond it, where his shadow, monstrous and grotesque, seemed flung headforemost into a shallow niche, within which there rested a flat slab of rock perhaps three feet in height.
To his distorted imagination the sudden suggestion seemed filled with a vague menace—as if the brooding shadow of death had reached forth to touch, to summon, to beckon with an imperious, chill finger there in that stifling abode of changeless dark.
Abruptly, as the quick flame ate downward to his fingertips, he made a short, backward step—stumbled—and the box fell from his nerveless hand, the match winked out, and at one stride the dominion of the dark enveloped him.
He bent swiftly, with frantic fingers searching in the mold, scratching, clawing in a fever of anxiety.
He found—nothing. Then, as if impelled from behind by an inexorable Force, he began to run, stumbling, falling, bruising himself against the sharp, unseen angles of the passageway along which he fled. . . .
Time had merged into an eternity of physical pain and mental torture, of corroding fear which left him in a sweat of agony as he fared onward in his blundering flight. The sense of direction which in the pitch black-
