SINCE the large chamber was in utter darkness, Saxe decided on recourse to a device which had served him well in similar situations of his boyhood among the mountains. As soon as Margaret moved and drew a little away from him, he spoke.

“We must step back to the passage-way,” he said. “From it, I can take our bearings, so that we can cross the place without floundering about haphazard in the dark.”

“Yes,” the girl answered. Her voice came very low, quavering a little.

Two paces brought them again to the entrance of the corridor. There, with a hand touching either side, Saxe made sure of the exact direction in which he faced, and from this he judged his course, for he remembered the relative positions of the passage by which they had come into the big room and of the shadows he had seen on the opposite wall. He had in mind as well his estimate of the diameter of the chamber, and so, when he had made sure of his direction he set off boldly, after again taking Margaret by the hand. He lengthened his stride a trifle, to make it the measure of a pace. When he had counted fifteen steps, he reduced his speed, and moved with caution, groping before him. A moment later, his hands encountered the wall. He was confident that he had held his course fairly straight in crossing the chamber, and was certain, in consequence, that the opening into the passage must lie a little to his left. He therefore drew Margaret in this direction. An instant later, to his joy, his left hand found emptiness. Without a word, the two hurried forward, and presently they saw before them a dim glow that was the first hint of outer light. Saxe fell behind the girl as the passage narrowed. Margaret quickened her steps to a run, and he held fast at her heels. In the same second with her, he issued from the cavern, and sent forth a huge shout, which was a little for escape from the cave, but chiefly for a primitive, masterful delight in the woman beside him. Margaret smiled sympathy with his mood—and her smile, it may be, was divided in its sources, even as was the lover’s cry of triumph.

The girl’s face was mantled with blushes. But she spoke bravely, with a dainty air of inconsequence.

“Why, how late it is!” She pointed toward the west. “See, the sun has set already, we were in there for ages.”

“Yes,” Saxe agreed. “And it’s like rebirth to come back—rebirth into a new, glorious life.” With an effort, he checked himself, for he would not embarrass her now, though passion bubbled to his lips. “We must paddle over to where the rest are, and let them know about the cave at once.”

The news brought by the two created a lively excitement among the others, along with a considerable feeling of relief, for the continued absence of Margaret and Saxe had been inexplicable, until Billy Walker quoted, with ostentatious carelessness:

At this utterance from the seer, who was by no means prone to sentimental rhapsodizing, Roy appeared at first puzzled, then enlightened, and he smiled—nor speculated more as to the whereabouts of his missing friend, while David grinned appreciatively, and accepted the innuendo as a sufficient explanation of Saxe’s absence even in this crisis of affairs.

For the rest, the three, with some assistance from Jake, had passed a busy afternoon, without accomplishing anything beyond a disheartening certainty that the gold had been very effectually concealed. Much of the cove was shallow, and Billy Walker had suited his convenience by pursuing his investigations of these portions from the launch which Jake guided to and fro as required. The clearness of the water made it possible to see the bottom distinctly except at the greatest depths, and in this comfortable fashion Billy conducted his search, smoking the inevitable black cigar. In the deeper parts, Roy, clad in a bathing-suit, made such examination of the bottom as he might by diving. David either assisted Billy in the scrutiny from the launch, or hunted over the islands near the shore. At no time did it occur to them to extend their researches so far as the island on which Saxe and Margaret had landed. They had just come to the conclusion that they must give over work for the day, and were again beginning to feel concern in regard to the continued absence of the heir himself, when they were startled by a hail in the voice of the missing man. They stared out over the lake, and perceived the canoe darting toward them, with Margaret plying a skilled paddle from the bow. Jake, who had just bent to the fly-wheel of the engine to crank up, dropped again to the bench; the others stood up and shouted. They had no least suspicion that the truants could be bringing news of the treasure. When finally the light craft ranged alongside the launch, and the story of the cavern was told, there were wonder and satisfaction. Roy was the first to make a suggestion as to the course to be pursued.

“The rest of you go on to the cottage,” he directed. “I’ll stay here on guard, in case our friend, the engineer, should have a mind to drop in on a visit. After dinner, let Jake bring me a snack to eat, and I’ll keep watch through the night. You—” he turned toward Margaret and Saxe—“can take me to the island, and show me the entrance to the cave, and then leave me.”

There were protestations from the others, offers to share the watch with him; but Roy resisted all importunities.

“I’d like to meet Masters again,” he declared, in his gentlest voice. “I don’t want any help.” They recognized the emphasis of finality, and forebore further argument.

But, when after dinner at the cottage Jake was about setting forth in the launch with supplies for Roy, which in addition to food included a pair of blankets and a lantern, David appeared at the boat-house, and accosted the old man just as the propeller began to revolve:

“Hold your hosses, Jake!” he called; and the boatman obediently threw out the clutch, and steered in a slowing circle to the dock. As he came alongside, David produced—with a deftness of movement that showed some degree of familiarity with gun-play—a very businesslike appearing automatic, which lay snugly in his palm. With his other hand, he brought forth a box of cartridges. These and the weapon, he extended toward Jake.

“For Roy,” he explained. Jake nodded, and stowed the armament in a locker.

The recipient of this equipment displayed small gratitude for his friend’s thoughtfulness. On the contrary, he sniffed when Jake, after beaching the launch on the strip of sand where Roy awaited his coming, presented the automatic and cartridges as first fruits.

“I sha’n’t need a gun,” Roy declared superciliously; and his pugnacious jaw was thrust forward yet once again. And, afterward, when Jake had accompanied him to the cavern with the blankets and the lighted lantern, the boatman’s well-meant offer to remain for the night was rejected almost with indignation. “You don’t understand, Jake,” Roy said, venomously. “I personally have an account to settle with that infernal engineer.”

The old man grinned a cheerful appreciation of the situation.

“Of course,” he remarked, in a matter-of-fact tone, “you got quite some hefty grudge agin ’im for the way he ducked your sweetheart.”

At this candid statement, Roy gaped in amazement.

“Why, how did you know she—” he began. Then, he halted in confusion. For the first time in many years, he felt himself incapable of speech.

Jake chuckled in high good nature, and deemed that explanation enough.

“Well, lick ’im good, if ye ketch ’im,” he exhorted; and straightway set out on his return to the cottage, where he and David were to serve as guards throughout the night.

Thus left to his own devices, Roy proceeded to make himself as comfortable as the circumstances of his situation would permit. He was sure that the enemy would not appear on the scene for some time yet, if at all, and in the interval before that possible coming he proposed to make himself at ease. To this end, he placed the lantern in the center of the chamber on the floor, and folded the blankets into a comfortable rug, on which he seated himself cross-legged, according to the fashion he had learned to like in the Far East. He was at pains to have the luncheon-basket conveniently placed before him, and now began an investigation of its contents with a curiosity sharpened by keen appetite. He smiled contentedly as he brought out a cold sliced fowl, fresh salad, a vacuum-bottle of hot coffee—the dozen other things that would have made a formidable array, had it not been for the strength of hunger with which he happily confronted them. As he renewed energy with this repast, Roy smiled at the contrast of its luxuriousness, as compared with many another that had been his lot in the wild places. He was alone in the wilderness, as often of old, but there the similarity ceased, for in those other places, there had been no dainties, such as the ones before him, no napkins of damask, or utensils of silver. And yet——

Roy broke off his musings, as he finished his third cigarette, and set himself to make arrangements for the night. He removed his blankets to a point against the wall of the cavern on the side opposite the entrance, where a tiny recess offered partial concealment. In this nook, he spread out the blankets, extinguished the lantern, stretched himself in a comfortable posture, and thus entered on the long vigil. He did not hesitate to doze, as he was sure that he retained his old habit of becoming alert at the faintest sound.

It was hours afterward when he became broad-awake in an instant. For a time, he lay motionless, all his senses quickened. The blackness of the chamber seemed impenetrable, yet his eyes stared steadfastly into the dark, expectant for aught that might befall. It was on hearing, however, that he depended chiefly to gather information, and his ears were set keenly. Yet, though he listened so intently, minute after minute passed, and there was no least interruption of the perfect silence.

Roy found himself in a quandary. He gave Masters credit for a shrewdness equal to the known unscrupulousness of the fellow. Undoubtedly, the engineer had lurked on some vantage spot of the shore throughout the day, and by this espionage had made himself acquainted with the progress of events on the lake. If he had perceived the landing of Margaret and Saxe on the island, as probably, almost certainly, he had, he would have known also of their long tarrying there, and of Roy’s remaining on the island. Perhaps from some elevation Masters had followed all their activities through a glass, and had been able by this method to inform himself precisely concerning the location of the cavern in which Roy was lying. Or, even, he might have come to the island, venturing in by the north-east side, so that his approach would not have been observed by the others. He could very easily have kept himself hidden afterward, as the unevennesses of the island and the profuse growth of trees and bushes offered ample concealment. But, whether the advent to the island had been earlier or later, Roy was sure that it was now accomplished, and that the engineer was there present in the chamber with him. His sixth sense spoke the assurance.

After all, it was sight, and not hearing, that at last served to guide the warden of the cavern. His eyes, which had been roving vainly in an effort to pierce the black space, suddenly caught a faintest glow. It was so indistinct, so subtly suggested rather than seen, that for a little Roy believed his vision deluded by some phosphorescence within his brain, which had set the nerves of sight to vibrating. He closed the eyelids for a moment, then looked again. The vague hint of radiance far remote still lingered. On the instant, doubt vanished; in its stead came certainty.

There could be no question that the light shone from a distance. Even the faintest spark anywhere near would have presented an appearance radically different from this. The diffusion of it was proof that its origin was in a light set a long way off. Finally, Roy guessed that the source of it was shut out from his direct vision by some obstacle intervening between him and it, while the nimbus extended beyond the barrier, and thus became perceptible. If this were, indeed, the case, it would be reasonable to suppose that the person responsible for the light was equally far away. The conclusion was by no means inevitable, but it was a fair assumption. Roy deemed himself justified in acting upon it.

Forthwith, he got to his feet, using every caution to avoid the least noise. When erect, he stood for a time listening, but could detect no sound. He had removed his shoes before lying down, and now he went forward in stockinged feet, very slowly, taking the direction whence the light seemed to issue, although its feebleness made the location far from sure. He used all the skill of which he was capable in this advance, and did indeed contrive to avoid making any noise. When he had gone for two rods, or more, he halted, and again listened. Nothing, however, rewarded his attention, and presently he renewed the tedious progress. Soon, it was borne in on him that the origin of the light was within one of the passages leading downward, of which Saxe had told him, and of which entrances had been observed by him while he was eating his meal, though he had not troubled to examine them. His sense of direction, strong naturally, had been developed by experience, and he was convinced that the radiance streamed from the passage that was on the left, as he faced the two.

From Saxe’s narrative, he knew that these tunnels were winding. The fact would readily explain the manner of the light, visible where he was in the big room like the afterglow from a sunset, with the cause of it hidden beyond the turnings of the corridor in which it burned, as the sun lies unseen below the horizon. With this understanding of the situation, Roy felt an accession of confidence, and at once moved forward more briskly in the direction from which the illumination shone. He held his hands outstretched, for the light was still too feeble to show objects round about him, even vaguely. Presently, his right hand touched stone. After another step, his left hand also came in contact with the wall, and he knew that he was within the passage, though whether that on the right or on the left he could only guess, nor did he regard the matter as of importance.

From this point onward, Roy’s advance, while made with unfailing caution, was much more expeditious. His stockinged feet seemed to possess a consciousness of their own, by which they searched for, and found, the fragments of rubble that were smooth enough not to cut, while solid enough not to yield a sound under the pressure of his weight. And, as he went forward, the light increased, little by little, until at last he could distinguish the sides of the tunnel through which he was passing. Yet, even when the illumination became sufficient to show what sort the footing, Roy chose still to trust his sense of touch, and held his eyes alert for anything that might appear in the distance beyond. He was aware that the passage descended for a time, then mounted slowly, only to slope downward again, and to continue thus. He noted, too, that sometimes it widened, until he could touch only one wall. He mistook the opening into the other passage for one of these broader places.

Roy aroused to the fact that the source of the light he sought was itself advancing, even as he advanced. There was no other possible explanation of the way in which it remained at about the same brilliancy, though he went forward with good speed. By this time, too, Roy was certain that the distance between him and the light was such as to leave little danger in the slight noise of his progress. So, he mended his pace, and soon perceived, with satisfaction, that the radiance noticeably increased. He maintained the quickened speed for a minute or two longer, then prudently moderated it again. Indeed, so bright was the light now that he made sure of being very close to the cause of it, and renewed the exercise of all his caution as he crept forward. That this was none too much—nor, indeed, enough—was shown by what presently followed.

Roy paused again, to examine the situation in detail. The brilliance of the light now assured him that its source was shut from him only by a single bend of the tunnel, which was hardly a rod in front. It was plain, then, that the time had come for determining the manner of his attack, since the moment could not be long delayed. He had no intention of resorting to the weapon with which David had equipped him. He planned that he would approach the turning of the passage noiselessly, and seek to reconnoitre from that point without being observed. Thereafter, as opportunity should serve, he would steal upon his enemy unaware, overpower the fellow, handling him with roughness enough to afford some adequate satisfaction for the outrage against May Thurston, and finally, when the villain had been reduced to passivity, hold him prisoner—to which purpose, at last, the automatic might prove convenient. The arrangement was admirably simple; there remained but to test its efficacy.

The length of tunnel thus traversed by Roy in his pursuit had been considerable. Throughout the latter portion, the slope had been downward, with frequent variations from a sharp incline to stretches almost level. In the place to which he had now attained, the slant was scarcely perceptible. At this distance from the big chamber, he had long passed beneath the waters of the lake. The location of the treasure might well be anywhere hereabouts, according to the saying of the miser’s cipher. Roy was moved to devouring curiosity to learn whether or no the man ahead of him had in truth come upon the gold. If so, the accomplishment should avail the scoundrel little, he vowed, and his jaw was thrust forward, as once again he advanced.

Roy looked to the placing of his feet for every step, neglecting no precaution to avoid aught that might give warning of his approach. In this stealthy fashion, he came to the turning of the tunnel, and then, after another delay to make sure that his presence remained unsuspected, he ventured to peer into the passage beyond the bend. His heart exulted! Surely, fate had delivered his enemy into his hand.

A hundred feet beyond the corner from which Roy looked, a lantern was set on the floor of the passage. This was the source of the light that he had trailed so painstakingly. It burned clearly; the radiance from it showed all about with distinctness. The conspicuous thing on which the beams shone was the form of Masters, who was kneeling and gazing fixedly down into an opening in the floor of the cavern. The man was on the farther side of this, and so had his face toward the watcher, but absorption in whatever was displayed beneath him prevented his noticing the presence of the newcomer. Roy was, therefore, able to continue his spying at ease. Curiosity, as well as discretion, bade him delay attack. He was eager to learn the nature of the engineer’s interest in the opening, and, too, the fellow’s position, facing up the tunnel, rendered impossible at the moment a rush that should take him by surprise. Undoubtedly, the engineer would make some movement presently, which would place him more conveniently for Roy’s purpose. In the meantime, it would be enough to observe, and to await the right instant for assault.

It may be that Masters, too, possessed a sixth sense. Roy could never be convinced that there was not something uncanny in the events that now immediately followed. Masters jumped down into the opening, where he stood with only head and shoulders exposed. Then, in an instant, the light of the lantern vanished—with that, the crash of a forty-five, thunderous there within the cavern. A second report came in the same instant. A searing pain touched Roy’s brow, and he lay unconscious.