Before the rod could descend, the earth-man’s fist had caught the Mercutian full in the face, driving him back upon the slanting dial of regulative levers beside the pivot-mounted ball. There was a shivering crash as he fell among the curving crystalline rods; and at the same instant, utter overwhelming darkness rushed upon the room and blotted out the banks of gleaming mechanism, the fallen Oumni, and the phantom of Shol.

IV

Standing uncertain and bewildered, the earth-man heard a low moaning from the injured Mercutian, and a loud wail of consternation from the corridor without, where the two groups of his pursuers had found themselves overtaken by darkness. The wailing ceased abruptly; and except for the moaning near at hand, which still went on, there was absolute silence. Howard realized that he no longer heard the mutter of the strange engines in the furnace-room. Doubtless their operation had in some manner been connected with the lighting system, and had ceased with darkness.

Howard still retained the suit of mouffa. Groping about, he found the metal rod that had dropped from the hand of the watcher. It would make a highly serviceable weapon. Grasping it firmly, he started in what he surmised to be the direction of the door. He went slowly and cautiously, knowing that his pursuers would have gathered to await him, or might even be creeping toward him.

Listening intently, he heard a faint metallic rustle. Some of the Oumnis, clothed in mouffa, were coming to seek him in the darkness. His own bare feet were soundless; and stepping to one side, he heard the rustling pass. With redoubled caution, he stole on toward the door, stretching one hand before him.

Suddenly his fingers touched a smooth surface, which he knew to be the wall. He had missed the door in his groping. Listening again, he seemed to hear a faint sound on the left, as if he were being followed; and moving in the opposite direction, along the wall, he encountered empty space and saw a dim glimmer of seemingly sourceless light.

His eyes were growing accustomed to the darkness, and he made out a mass of dubious shadows against the glimmering. He had found the door, which was lined with waiting Oumnis.

Lifting his bar, he rushed upon the shadows, striking blow after blow, and stumbling over the bodies that fell before his onslaught. There were shrill cries about him, and he broke from chill, mouffa-sheathed fingers that sought to clutch him in the gloom. Then, somehow, he had broken through, and was in the corridor.

The glimmering, he saw, came from the cavern of machines, where the hidden furnace still burned. Into the dying glow that lit the entrance, there came hurrying figures, each of which appeared to have an enormous Cyclopean eye of icy green. Howard realized that more Mercutians, bearing artificial lights, were coming to join the pursuit.

Keeping close to the corridor wall, he ran as fast as he dared in the solid blackness, toward the cavern of the Roccalim. He heard a stealthy metallic rustling, as the foremost Oumnis followed; and glancing back, saw them dimly outlined against the remote glow. They came on in a cautious, lagging manner, as if they were waiting for the new contingent with the green lights. After a little, he saw that the two parties had united and were following him steadily.

Fingering the wall at intervals as he ran, Howard reached the entrance of the large chamber in whose center stood the Roccalim. The lights were gaining upon him rapidly. Calculating in his mind, as well as he could, the direction of the opposite doorway, giving on the main tunnel that led to the incline, he started toward it. As he went on, he veered a little, thinking to avoid the monstrous plant-growth. It was like plunging into a blind abyss; and he seemed to wander for an immense distance, feeling sure that he would reach the opposite wall at any moment.

Suddenly his feet tripped on an unknown obstruction, and he fell at full length, landing on what seemed to be a tangle of great hairy ropes that pricked his bare skin in a thousand places. Instantly, he knew that he had collided with the Roccalim.

The mass of python-like branches lay inert beneath him, without a quiver of animation. Doubtless, in the absence of light, the queer, semi-animal growth was torpid.

Pulling himself from the spiny couch on which he had fallen, Howard looked back and perceived the thronging of green lights, cold and malignant as the eyes of boreal dragons. His pursuers were entering the cavern, and would overtake him in a few instants.

Still clutching the mouffa garments and the metal bar, he groped across the tangle of branches, pricking his feet painfully at every step. Suddenly he plunged through to the floor, and found that he was standing in an open space where the heavy creepers, descending from the bole, had parted on either side. Crouching down, as the lights approached him, he found a low, hollow place into which he could crawl beneath the branches, close to the cactus-like stem.

The creepers were thick enough to conceal him from casual scrutiny. Lying there, with their prickly weight upon him, he saw through narrow rifts the passing of the green lights toward the outer cavern. Apparently none of the Mercutians had thought of pausing to examine the mass of Roccalim branches.

Emerging from his fantastic hiding-place, after all the Oumnis had gone past, Howard followed them boldly. He saw the vanishing of their icy lamps as they entered the outside tunnel. Moving again in utter darkness, he found the exit. There he recovered the running pencils of light, cast by the hurrying lamps as their bearers went toward the incline.

Following, Howard stumbled against an unseen object, which was either the vehicle used by Agvur, or another of the same type. Probably, in the shutting-off of power, these vehicles were now useless: otherwise, some of them might have been employed by the earth-man’s pursuers. Hunters and hunted were on an equal footing; and realizing this, Howard felt for the first time an actual thrill of hope.

Going on, with the lights moving steadily before him, he started up the interminable incline which led—perhaps—to freedom. The tunnel was deserted, except for the hunters and their human quarry; and it seemed as if the multitude of Oumnis seen by Howard on his arrival with Agvur had all retired with the falling of darkness. Perhaps they had to for the usual three-hour term of night and repose.

The light-bearers appeared to disregard all the side passages that ran from the main tunnel. It occurred to Howard that they were hastening toward the surface exits, with the idea of cutting off his possible escape. Afterward they would hunt him down at leisure.

The incline ran straight ahead; and there was little danger of losing sight of the lights. Howard paused an instant to slip on the suit of mouffa, hoping that it might serve to deceive or baffle his hunters later on. The raiment was easily donned, and fitted him quite loosely; but the unfamiliar intricate method of fastening eluded his untaught fingers. He could not remember quite how it had been done; so he went on with the strange garment open at the breast. The queer elongated heels, made to accommodate the spurs of the Immortals, flapped behind him.

He kept as much as possible the same relative distance between himself and the Oumnis. Glancing back, after awhile, he was horrified to see, far down, the tiny green eyes of another group of lights following him. Evidently others had rallied to the pursuit.

It was a long, interminably tedious climb—mile after mile of that monotonous tunnel whose gloom was relieved only by the sinister points of green light. The Mercutians went on at a tireless pace, unhuman and implacable; and only by ceaseless exertion, half walking, half running, could the earth-man maintain his position midway between the companies of lamps.