For once Doctor Miranda had nothing to say. To the eager queries of those about him he returned a grimace and a scowl of rage. Then he asked savagely for Mrs. Quayle.

“There is her neckalace,” he said indignantly, letting go his hold on that extraordinary piece of jewelry and scrambling to his feet with as much dignity as was left to him.

“Will you tell me what all this means?” demanded Leighton sternly.

“How I know?” retorted Miranda, glaring venomously at him. “I pull the neckalace from the neck, and it fly from me. When I follow, it fly more fast—and it get stronger and it fly harder every time until it touch the rock. Then it stop and not come loose.”

Sure enough, on the greenish-black rock over which they were bending, the necklace was spread out to its full length. With a quick jerk, Leighton dislodged one of the ends from its resting place. Letting it go, it returned to its original position with the sharp snap of a steel spring.

“A magnet! The most amazing magnet ever heard of!” exclaimed Leighton.

“A magnet that pull gold!” scoffed Miranda. “That is the foolishness!”

But Leighton was right. Each time the necklace was pulled away it was drawn back to the rock by a strong, invisible force. Repeated trials brought the same result. Leighton’s curiosity was excited as it had never been before; but his most careful examination of the strange phenomenon failed to detect anything more than the fact that the substance exerting this unknown force was not stone but something more nearly akin to metal. It was neither so heavy nor so hard as iron. To the touch its surface faintly resembled the adhesive softness of velvet, although a blow from a stone, causing a clear, ringing sound, left not the slightest mark upon it. In the main, this block of metal—or whatever it might be called—was a deep black, tinged with a variegated shade of green that played over it according to the angle at which the ray from a light held above it was reflected. Dark lines of green followed the indentations traversing its surface. Cylindrical in shape, it weighed, according to Leighton’s estimate, at least a ton. Imbedded in a deep groove around its center was a rope, measuring two inches in diameter, of pliable fiber, resembling the long lianas that festoon the trees of a tropical forest. This rope lay in a seamanlike coil on the ground, with the further end attached to the transverse beam of the scaffolding overhead.

“It is a magnet, nothing else,” reiterated Leighton; “a magnet of a kind utterly unknown to science. All we can say is that this black metal has an affinity for gold—unless it turns out that Mrs. Quayle’s jewelry is merely iron gilded over.”

This doubt as to the genuineness of the housekeeper’s treasures was promptly denied, however, by Una, who guaranteed their sterling quality.

“Let us test the rest of her jewelry,” proposed Leighton.

To this further demand on her property Mrs. Quayle, wedged in between two rocks on the path where they had left her, too terrified to move, offered only a feeble protest. It mattered little to her, in her present condition, if her bracelets and brooch followed the necklace to their doom. One by one they were, accordingly, removed by Una, who, probably because she was less excitable than Miranda—and because, too, she had profited by his untoward experience in the same undertaking—was able to handle these pieces of jewelry without mishap. The force with which they were pulled towards the Black Magnet, however, and the tenacity with which they stuck to it, gave ample evidence that they answered to the same influence that still held the necklace.

“That is enough,” said Leighton triumphantly. “The thing is proved. This is a gold magnet. If we lived in the Middle Ages we would call it the Philosopher’s Stone. The theory that such a substance exists has attracted scientists who were more given to dreaming than practical observation. In this age we have neither looked for it nor believed in the possibility of its existence. And here it is!”

“What it make here?” demanded Miranda. “Tied by a rope to the machine—some one use it.”

The inference, logical enough, certainly, increased Leighton’s excitement. That the magnet was known and used by the inhabitants of the cave—if there were inhabitants—was evident. Under certain conditions a bar of metal that could attract gold with such force as that displayed by the Black Magnet would be of untold value. Here, where there were no evidences of mining operations, and attached to this primitive machine, it was difficult to explain what it was actually used for.

Leighton, more and more mystified, determined that the best way to solve the puzzle was to operate the machine in the manner indicated by its structure. It was not, as he pointed out—but as they in their first excitement imagined—a gallows. Instead, it was a winch, built in the most simple and archaic fashion; and as the Black Magnet was attached to it, the evident purpose was to hoist that huge body from the ground. Before testing this theory, Mrs. Quayle, who had recovered from her collapse sufficiently to join the others, insisted that her jewelry should be released from the magnet. Suspicious of the intentions of some of her companions, she was determined to regain possession of her treasures at once. But, as it was apparently impossible to wear her jewelry with comfort, or even safety, in the immediate vicinity of the Black Magnet, necklace, brooch and bracelets were removed to a distant corner of the corridor and there placed beneath a pile of stones. This done, the four men started to work the two long handles of the winch. At first these were turned with difficulty, the resistance proving, at least to Leighton’s satisfaction, that the machine had not been used for a long time. Gradually, however, the coil of liana was transferred from the ground to the transverse beam overhead until it pulled taut with the magnet beneath.

Then came the real trial of strength. The magnet wouldn’t budge. Miranda puffed and grumbled over the task, declaring it impossible. The rest stopped and rubbed their arms ruefully. But Leighton was inexorable. Encouraging the others, and keeping them at it, by dint of increased exertion—to which Una brought additional assistance—the great Black Magnet was finally dragged from its moorings and held suspended just above the ground. It formed a perfect cylinder, about four feet long by a foot and a half in diameter, and must have weighed, they estimated, considerably over a ton—ten tons, vowed Miranda. On a winch of modern design this weight would not have been difficult to lift. But the hoisting apparatus they were using lacked the ordinary adjustments for counterbalancing such weights; hence, the muscular force needed proved no small matter.

“It take twenty men to lift this magnet,” growled Miranda.

“Twenty men could do it more easily than four men and a woman, undoubtedly,” replied Leighton. “But four can do it.”

And he was right. Inch by inch the magnet rose from the ground—for what ultimate purpose was not very clear, any more than that it was thought necessary by Leighton, in order to discover the use to which this strange bar of metal had been put, first to test the appliance obviously intended to bring it into action. It reached a height of one foot from the ground, then two, then three feet; then it stopped. There were groans and smothered imprecations, and it looked very much as if the huge bar of metal would come crashing down to the ground again. But the men, urged on by Leighton, did not give in. And then—there was a grating noise, as if some hidden mechanism in the scaffolding had been set free. After which a strange thing happened. The transverse beam at the top of the windlass detached itself from one of the uprights supporting it and, using the other upright as a fulcrum, slowly swung to the wall of the cave, where it rested in a socket, bringing the magnet that was suspended from it, directly over a shelf-like projection beneath.

“Keep on! Keep on!” cried Leighton encouragingly. “Now we will see.”

Thoroughly aroused, the others redoubled their exertions. The magnet remained stationary for a few seconds, the liana supporting it tightening with every revolution of the drumhead at which the men were laboring. Then it slowly disappeared downward, the liana uncoiling itself, thus reversing the movement that before had carried it upward. There was a gradual increase in the momentum of its descent, followed by the splashing sound caused by the impact of a heavy body upon the surface of a pool of water; after which the liana was paid out until it reached its full length—when it suddenly slackened and came to a full stop.

“There, Mrs. Quayle, is your water,” announced Leighton.

“Water!” sneeringly echoed a voice from the darkness behind them. “Say, rather, there is the secret of Guatavita!”

“Raoul Arthur!” exclaimed the others.

Letting go the handle of the windlass, they rushed to the spot where the Black Magnet had vanished. There, at one side of the rocky projection, stood Raoul, pale and haggard, the light in his lamp extinguished.

“I suspected this,” he said, as if his sudden reappearance among them were the most natural thing in the world. “I knew from the direction of the path that it led back to the lake. I have been trying to reach this place for years. Oh, yes! I had heard something about it before—I don’t deny that. But, of course, I expected to stay by you. So, when you started to leave the cave I came back, expecting to rejoin you. As I was examining the machine I was attacked by two men, thrown to the ground and left unconscious. I came to myself a few minutes ago—in time to congratulate you, it seems, upon solving the mystery of the cave.”

“That is strange,” said Leighton coldly. “You left us, without a word, at a time when you were needed. The attack that you say was made upon you we should have heard. But—we have heard nothing.”

“Believe me, or not, as you like; it is true,” was the sullen reply.

“Why do you say we have the secret of Guatavita?”

“Look!”

Raoul pointed to the projection in the wall behind which the Black Magnet had disappeared. It was not a shelf, as they had at first supposed, but the opening of a shaft, or well, that slanted downward at an angle that in the course of fifty feet, or less, would reach considerably beyond the vertical line of the cave’s wall. In shape this shaft was oblong, slightly larger in length and in breadth than the Black Magnet. It was evidently of artificial origin, its four walls being perfectly smooth and without irregularities of line. Even by one who had not seen the magnet descend into this shaft, its intended use as a sort of runway for raising and lowering heavy bodies would be quickly recognized. But where it led to was another matter. One thing was easily discovered: where it reached a point some twenty feet below the level of the cave’s floor the shaft was filled with water. Beyond this, of course, nothing could be made out. It was to the bottom of the pool thus indicated that the magnet had plunged.

“It is a well hewn out of the rock by Indians—or perhaps by Spaniards digging for gold,” said Leighton.

“I believe that we are the first white people who have ever stood in this place,” said Raoul; then added, “unless David Meudon was here three years ago.”

“But what is it about?” demanded Miranda impatiently. “What for is the magnet, and this well, and this machine?”

“Pull up the magnet and see for yourself,” was the laconic reply.

“Caramba! That will be impossible,” protested the doctor, not relishing the prospect of another turn at the machine.

“It is the logical thing to do,” agreed Leighton.

The rest shared Miranda’s aversion to another bout at the winch; but Leighton, backed by Raoul Arthur, finally persuaded them that their only hope of escape from the cave depended on keeping at this puzzle until they had solved it, and that the first step in this direction was to hoist the Black Magnet from its watery resting place at the bottom of the shaft. Reluctantly obeying the command, they again seized the long handle of the windlass. This time it was fortunate they had Raoul to help them, since the resistance offered by the magnet, which now had to be hauled up an inclined plane by means of a rope nearly one hundred feet in length, was considerably greater than before. The windlass creaked and trembled as revolution after revolution of the drumhead slowly brought the great black bar of metal nearer to the surface. They could hear the far off swirl of the water as the ascending liana vibrated through it. Minutes that seemed to lengthen into hours passed without appreciable result. Then, at last, they heard the water rising as the magnet reached the mouth of the shaft. There was an additional strain on the liana, followed by the noise of a commotion in the subterranean pool as the liquid streams poured back from the emerging body.

But still the end to their work was not in sight. With every turn of the handle the weight of the body at which they were pulling seemed to increase. Mrs. Quayle, sole spectator of what was happening, watched the opening of the well with dismal apprehension, convinced that some dreadful transformation had taken place in its hidden depths. When the top of the magnet finally rose into view she shrieked hysterically. To her notion the great black body had an uncanny look; it had turned into a devil, for aught she knew, filled with evil designs against them. Anything that was supernaturally horrible, she believed, could happen in this cave—and there was enough in her recent experiences, indeed, to give some color to her belief.

But, devil or djinn, the water dripped and splashed in sparkling runlets from the shining body of the Black Magnet that had gained in luster since its submersion in the well. It seemed more alive than before, more capable of exerting the mysterious force that had played such pranks with Mrs. Quayle’s jewelry. As it cleared the top of the well the arm of the windlass to which it was hung, as if obeying some invisible signal, detached itself from the socket in the wall and slowly swung back into its original position between the two uprights of the machine. Here, as before, a reverse motion took place. The Black Magnet was poised for a moment in the air. It then descended to the ground, resting, finally, in the same spot where the explorers first discovered it.

A sigh of relief escaped them. Hoisting heavy weights was not much to their taste and they were glad the task was over. Then they rubbed their eyes, half expecting to see something miraculous, some sudden transformation as a result of their labors. But the Black Magnet, except for the brilliance due to its bath in the depths of the earth, looked exactly as it was before. This, it must be confessed, was disappointing to those who had been promised great rewards for toiling so patiently at the windlass. Raoul had declared the experiment would solve the secret of Guatavita. But they failed to see how a wet rock—or bar of metal, whichever it might be—with mud sticking to it, had any connection with a secret. Raoul, however, was not disconcerted. Getting to work on the magnet, he examined minutely every inch of its surface. At first he found nothing. Then, to the amazement of the others, he extracted from one of the large fissures in the magnet a thin disc encrusted with the microscopic growths that form on metals that are long subjected to the action of water. This disc proved its metallic nature by the force needed to release it from the magnet. Much of the brown matter sticking to it was wiped away with a cloth, the more tenacious growth beneath was rubbed and scraped with a sharp stone. When the scouring was finished Raoul triumphantly held up the disc. It was a dazzling plate of gold, thin and flexible, rudely carved to resemble a human being. In size it was not more than the palm of one’s hand, somewhat of that shape, a trifle longer and narrower, with a projection, intended to depict a man’s head, face and neck, like a pyramid standing on its apex, upon which were traced in embossed lines three loops to represent the mouth and eyes, with another line running down the middle, long and straight, to represent the nose. The body of the figure was similarly carved—raised lines folded over the stomach for arms, with various loops and coils around the neck and chest, intended, doubtless, to indicate the ornaments and insignia of rank worn by the image or, rather, the human being or god for which it stood. All this was done in the finest gold tracery, which, if it lacked some of the subtleties of the goldsmith’s art as we know it, was expressed, nevertheless, with admirable delicacy and firmness. In the head of the figure was a round hole showing, doubtless, that the disc was worn as a pendant by its owner, or was hung as a votive offering before his or her household deity.

Leighton had seen figures of like character and workmanship in Bogota, where they were exhibited as ornaments worn by the ancient Chibchas. Usually they were said to have been brought up by divers from the bottom of Lake Guatavita. Hence, there was little doubt as to the origin and antiquity of the disc presented to them by the Black Magnet. But how this disc came to be at the bottom of a well in this vast subterranean labyrinth was not so easily answered. If this disc was the much talked of clew to the lost treasure of the Chibchas, and to all the other mysteries that seemed to crop up at every step the further they went into this cave, it was not an easy one to run down. And then, Miranda, who had insisted all along that by following the direction in which they had been going they were bound to reach the lake, blundered upon the answer to the whole question.

“It is Guatavita!” he said.

Of course, that was it! Herran and Leighton gasped for a moment as they took in the idea, and then they agreed that Miranda was right. Raoul smiled enigmatically as they discussed the problem in detail.

“Well, do you understand it now?” he asked. “Have you discovered Guatavita’s secret? I wish I had known it three years ago!” he added bitterly.

“Ah! I see—I see!” shouted the doctor excitedly. “There is the well that come out at the bottom of the lake. Here is the magnet that go down there just when the people throw in all the gold. And then it come back here—and no one know except the king and his family. So, every year, they take all the gold of the country. Ah! they are very wise leetle fellows, those kings!”

“Then, if this is true,” said Leighton meditatively; “if this well has its outlet at the bottom of the lake, and was made and used secretly to collect, by means of the Black Magnet, the treasure offered by the people in the Feast of El Dorado, to-day there is no gold left in Guatavita.”

“If it were drained of all its waters,” remarked Raoul, “I believe that the emptied basin would be found to contain nothing more than a few stray gold ornaments—like the one you fished up just now—that failed to reach the Black Magnet when they were flung into the lake centuries ago.”

“Your plans to empty the lake, then, are useless?”

“After what I have learned to-day, added to what I have long suspected, I should say—quite useless.”

“But the fabulous amount of treasure those deluded people threw into the lake for centuries——?”

“Has all come up here, where we are standing now, caught by the Black Magnet.”

“He fish very well, this leetle stone,” said Miranda, caressing it fondly. “He catch more, better fish than the whole world.”

“Where is all that gold to-day?” demanded Leighton.

“Ah! Where!”

“Good heavens! What is that?”

While Leighton and Raoul were discussing the old problem of what became of the Chibcha Empire’s far-famed treasure, the others had wandered away from the Black Magnet and were examining some of the strange objects in its immediate vicinity. The more familiar they became with this portion of the cave, the more signs they saw in it of human occupation. For one thing, the place was honeycombed with paths, most of them radiating from the shaft that sank to the bottom of Lake Guatavita. These paths led in different directions; but there was no way of telling whether any or all of them had been recently used. This question was of more immediate interest than the one connecting the cave with the fate of the ancient Chibchas. If this cave was inhabited to-day—if it was the hiding place of a lawless gang of Bogotanos, for example—it was well for the explorers to be on their guard. Herran was particularly alive to this possibility, and he was quick to heed, therefore, Mrs. Quayle’s terrified exclamation, which she repeated—

“Good heavens! What is that?”

It was at the head of one of the paths, running behind the close ranks of stalactites before which they had found their way from the large open cave beyond, that Mrs. Quayle stood, her eyes round with excitement, pointing vaguely at something in front of her. But the others could see nothing. Indeed, it was hard to tell whether she had really seen anything worth serious investigation, her chronic nervousness had such an uncomfortable habit of discovering specters—that did not exist—in every dark corner. Then, too, clusters of stalactites had a way of taking on odd, fantastic shapes that might easily seem to be alive even to the cool-headed. But this time there really was substance to Mrs. Quayle’s fancies. She continued to point down the pathway of stalactites, crying repeatedly—

“What is that?”

“Well, what is it?” demanded Leighton.

“The man in the toga! The man in the toga!” she cried breathlessly.

The others crowded about her.

“It is nothing!” said Miranda incredulously.

“It is! It is!” whispered Una. “I just caught the flash of white drapery at the bend in that farthest corridor.”

Raoul laughed. “You are mistaken,” he said. “Nothing is there now, that’s certain.”

They stood silently watching the dark green-and-white figures that stretched away in closely huddled ranks before them. But they could detect nothing that answered to Mrs. Quayle’s description. There was nothing that moved, nothing human, in all that glittering array of grotesque forms. Then, there was a sharp, clinking sound, as if the brittle point of a stalactite had been broken off and had fallen to the ground.

“We are watched,” said Leighton in a low voice. “Whoever they are, these people have some reason for following us—and keeping out of the way.”

“Time to be on our guard,” said Herran in Spanish to Miranda, who assented vehemently.

“Nonsense!” exclaimed Raoul.

“Ah! You say that?” growled Miranda suspiciously. “This is one trap of yours, then!”

The accusation added to the general alarm. Raoul protested scornfully; but before he had time to clear himself he was covered by two huge revolvers, drawn simultaneously by Herran and Miranda.

“It is not so easy!” threatened Miranda, whose excited flourish of firearms endangered the others quite as much as it did Raoul.

“Thank heaven, we have guns!” murmured Andrew, who had produced a harmless looking pocket-knife which he brandished ineffectively.

“This sort of thing is very annoying,” said Leighton, addressing Raoul, who began to show uneasiness. “There’s no denying that your disappearance was suspicious. Then we find you here in a place that is evidently known and frequented by others. Your explanation is unsatisfactory. Then, when the presence of these hitherto invisible people is quite certain, you try to divert our attention from them.”

“You are talking nonsense,” said Raoul disgustedly. “You intimate that I am in league with the inhabitants of this cave against you. That means, I must have lured you here deliberately to do you harm. Please remember that it was you who planned this expedition, and that I had not ventured in here so far before.”

“Who knows! You seemed familiar enough with the secret of the Black Magnet.”

“Take us out of here, my fellow, and we believe you are not one scamp,” said Miranda brusquely.

“I am not bound to do anything of the kind, even if I could,” retorted Raoul. “Look out for yourselves.”

“So! that is good,” commented Miranda. “We take the advice. Here we can do nothing. Into Guatavita we cannot jump through this well. Me—I am too fat!”

The bustling doctor’s show of energy proved infectious. He and Herran unceremoniously pocketed their revolvers, leaving Raoul at liberty to do as he pleased, while they looked about for a way of escape.

Since he had become suspicious of Raoul, Leighton was inclined to trust the leadership of the two South Americans. The latter, convinced that there was no way out from this part of the cave, determined to go back to the central chamber, hoping to find there the entrance to the tunnel leading to the outside world. They hit on this plan because they feared an ambush on any of the labyrinthian trails leading off in other unexplored directions. The rest agreeing, they set out along the path flanked by the grove of stalactites, traveling at a quicker pace but with greater caution than before. Miranda and Herran marched ahead with revolvers drawn, Andrew in the rear still holding his pocket-knife ready for action. They had been delayed on Mrs. Quayle’s account, for that lady, in spite of her anxiety to get away, had refused to budge without her jewelry. But it was not easy to satisfy her demand. For, when the jewelry was taken from its hiding place beneath a rock, it still showed the same strong tendency to fly to the Black Magnet. This distressed Mrs. Quayle, who refused to touch the treasures that she was at the same time loath to part with. But a compromise was finally effected by tying all the jewelry securely around Andrew’s waist. This arrangement appeased the owner—but it gave an uncomfortable backward pull to every step the schoolmaster took, who thus resembled, in walking, a ship sailing against the wind. This inconvenience, however, steadily decreased as they came out of the disturbing region of the Black Magnet, until finally these ancient heirlooms of Mrs. Quayle’s regained their natural composure.

But there were other things besides the Black Magnet to interrupt their progress. No sooner had they gotten well under way and were congratulating themselves on their escape from mishap so far, than they were startled by a wild and piercing strain of music, seeming to come from the grove of stalactites before which they were hurrying. Amazed by so singular an interruption, they stopped short and looked fearfully about them. A sound of scornful laughter blended with the music.

“Raoul!” muttered Leighton.

But there was nothing to be seen of the strange American whose mocking laughter they were sure, nevertheless, they had heard. Then the music grew louder and louder, as if the musicians were steadily approaching in their direction. The music itself was subtly different, in tone and pitch, from anything played in the outside world. The high notes evidently came from wind instruments, but of a unique quality and caliber. Mingling with these notes, and sustaining the bass, were the heavy beatings of drums of the kind still used, although deeper and mellower, by the native Indians in their festivals.

The melody produced—if it could be called a melody—was of an extraordinary character. Its effect, its charm—for it had unmistakable charm—was quite impossible to define. In some respects it resembled the monotonous chantings peculiar to most primitive races, occasionally, as was customary with the latter, rising and falling, whole octaves at a time, in a wailing key. In the main, it carried a sort of theme, emotional and inspiring, that was far too complex to be attributed to the uncultivated musical taste common to savagery. There was an exultant swing to the measure, a lilting cadence that betrayed a fine esthetic sense, a rich imagination coupled with the simplicity and freedom that has not felt the pressure, except very remotely, of our western civilization. Such music was good to listen to—and under ordinary circumstances the explorers would have been content to listen and nothing more. But curiosity, and some remnant of fear the lulling influence of the music had not dissipated, kept them on the alert. Their fate depended, they felt, on these musicians. They must find out who they were before it was too late to retreat. And then—presently—through the clustering green and white stems of the stalactites, they caught sight of them.

They were over twenty in number, moving, as nearly as the unevenness of the ground would permit, in time to the choral march they were playing. At sight of them Mrs. Quayle didn’t know whether to be pleased or terrified. For the music was such an enchanting, soothing sort of thing, and the players so mild, benignant of aspect, anything like fear seemed out of place. But, on the other hand, the strange instruments they carried, their outlandish dress, the whole effect of them, in a way, was distinctly unearthly, supernatural—and Mrs. Quayle drew the line at the supernatural. So, she ended by being simply amazed beyond measure—and her companions shared her feelings in lessening degree. Miranda and Herran, dumbfounded by the apparition, forgot to handle their revolvers in the warlike fashion they had intended with the first approach of a foe; Andrew gaped in an open-mouthed sort of dream, during which his pocket-knife came imminently near doing fatal execution upon himself, while Una and Leighton, forgetting their anxiety, were lost in admiration of the delicious music and of the spectacle before them.

One and all of this singular band of cavemen were clothed after the fashion described by Andrew. Each wore a loose white mantle, or toga, that draped the figure in voluminous folds, adding to the grace and freedom of movement with which they kept time to the music. Their feet were shod with sandals, their heads encircled with bands of white cloth from the flying ends of which hung ornaments of gold and emerald. The musical instruments upon which they played were long, slender tubes, curving upward at the extremity, of a metal that glittered and sparkled like the purest gold.

Most singular of all was the light that each of these musicians carried. This light came from neither torch nor lantern, but radiated in sparks and flashes from oval disks worn, jewel-wise, on the breast. By what fuel these incandescent fires were fed was not apparent. They burned with a clear white brilliance, illuminating each flowing figure with startling vividness, and filling the beholder, ignorant of their nature, with wonder at their admirable adaptability to the needs of a subterranean world.

To Leighton these strange lights were much more mystifying than all the rest of the apparition—for as yet it was difficult to regard the approaching throng as being anything more real than an apparition that one expects to have vanish away almost as soon as it makes its appearance. But these musicians, weird and unearthly though they first seemed when seen at a distance, as they drew nearer, proved to be substantial, flesh-and-blood human beings right enough. Their dark skins and aquiline features gave evidence, for one thing, that they were of Indian origin and not inhabitants of the remote, invisible fairyland that they appeared to the fervid imaginations of some of Leighton’s companions. Doubtless, argued the savant, they were a band of revelers—or bandits—from the city to whom the secrets of the cave were familiar. But where they had picked up such extraordinary means for the illumination of their merry-making was more than he could fathom. Lights? They were unlike any lights he had ever heard of. All that he could make of it was that these illuminated disks belonged to the marvels of a hitherto unknown world of science, marvels among which he counted the Black Magnet and—possibly—that disappearing wall at the entrance to the cave.

As these people showed no sign of hostility, the explorers began to hope that through them they would win their way out of the cave. Certainly, they were worth cultivating with this end in view. Hence, Miranda and Herran looked stealthily at their revolvers and restored them as quickly as possible to their hip-pockets, while such a burst of confidence seized Mrs. Quayle that she prepared and was actually seen to exhibit one of her most ingratiating smiles for the benefit of the approaching Indians, at the same time expressing in a loud voice to Una her approval of their music.

This pleasant feeling, however, that they were about to regain their liberty did not last long. The Indians, although showing no unfriendliness, gave unmistakable evidence that they meant to control the movements of the explorers. Still playing on their trumpets and beating solemnly on their drums, they marched around them, bowing courteously enough, but intimating at the same time that they were acting upon a definite plan that could not be interfered with. Somewhat dashed by this singular behavior, which was the more difficult to meet just because it lacked outward menace, the explorers conferred hastily together, hoping to hit on a safe line of action. The men of the party, suspicious of the friendly attitude assumed by the Indians, favored immediate resistance. Their first flush of confidence in them was gone. Herran and Miranda, especially, were doubtful of the intentions of these strange people. From whatever motive, it seemed to them that the latter had deliberately planned their capture, evidently carrying out in this the orders of some one in authority over them. That these orders might come from Raoul Arthur was their principal cause for alarm. The departure of the American miner, under every appearance of treachery, marked him out as one to be feared. He was not, it is true, among the Indians who were surrounding them in their glittering line of dancers, but his absence was not proof that he had nothing to do with this odd demonstration. But—how resist a party so superior to their own in number, one that had already gained an obvious advantage of position over them. Leighton was doubtful what to do; Andrew was helpless; Mrs. Quayle was temporarily lost in admiration of the picturesque circle of dancing figures, all regarding her with gratifying amiability. Una alone insisted that the friendliness of the Indians was genuine, and that their own safety depended on obeying them. As a compromise it was decided to talk to these people—to find out what they were after. For this diplomatic duty Miranda and Herran were chosen.

Although the energetic little doctor was certainly not gifted with an unusual amount of tact, he had at least the merit of directness, and lost no time in calling the attention of the dancers to his desire to come to an understanding with them.

“Do you talk Spanish?” he shouted brusquely in that language.

“Surely, Senor Doctor,” gravely replied a tall personage whose dignity of bearing and the fact that the border of his flowing toga was distinguished by a decorative design in embroidered gold indicated his superiority in rank over his comrades. “Surely, some of us talk Spanish.”

Having given this assurance, the speaker checked the music and dancing of the others and stood, with the air of one accustomed to ceremonious usage, waiting to hear further from Miranda.

“Yes, I am doctor, famous doctor,” said the latter, bustling up to the speaker and looking him over as if he were about to claim him for medical purposes. “I cure thousands and thousands with my pills. But how you know I am doctor?”

The Indian smiled, inclining his head graciously before answering.

“Doctor Miranda is so famous every one knows him.”

Ordinarily the vanity of Miranda was easily touched, but just now he was too suspicious to be beguiled by the compliment.

“Caramba!” he snorted; “and who are you?”

“I am Anitoo.”

“That is not Spanish,” said Miranda sharply.

“I am not Spanish,” replied Anitoo stiffly. “I come from an ancient race that ruled here long before there were any Spaniards.”

“Well, Senor Anitoo—you say it is Anitoo?—that may be. You are Indian—Chibcha Indian, perhaps—and not Spanish, not Colombian. But what do you make in this cave?”

Anitoo smiled broadly.

“This is the home of my people for many centuries,” he said. “And now, suppose I ask you a question. What do you make in this cave?”