It was at the moment that Tarzan turned from the closeddoor to pursue his way to the outer world. The thingcame without warning. One instant all was quiet andstability--the next, and the world rocked, the torturedsides of the narrow passageway split and crumbled,great blocks of granite, dislodged from the ceiling,tumbled into the narrow way, choking it, and the wallsbent inward upon the wreckage. Beneath the blow of afragment of the roof, Tarzan staggered back against thedoor to the treasure room, his weight pushed it openand his body rolled inward upon the floor.

In the great apartment where the treasure lay lessdamage was wrought by the earthquake. A few ingotstoppled from the higher tiers, a single piece of therocky ceiling splintered off and crashed downward tothe floor, and the walls cracked, though they did notcollapse.

There was but the single shock, no other followed tocomplete the damage undertaken by the first. Werper,thrown to his length by the suddenness and violence ofthe disturbance, staggered to his feet when he foundhimself unhurt. Groping his way toward the far end ofthe chamber, he sought the candle which Tarzan had leftstuck in its own wax upon the protruding end of aningot.

By striking numerous matches the Belgian at last foundwhat he sought, and when, a moment later, the sicklyrays relieved the Stygian darkness about him, hebreathed a nervous sigh of relief, for the impenetrablegloom had accentuated the terrors of his situation.

As they became accustomed to the light the man turnedhis eyes toward the door--his one thought now was ofescape from this frightful tomb--and as he did so hesaw the body of the naked giant lying stretched uponthe floor just within the doorway. Werper drew back insudden fear of detection; but a second glance convincedhim that the Englishman was dead. From a great gash inthe man's head a pool of blood had collected upon theconcrete floor.

Quickly, the Belgian leaped over the prostrate form ofhis erstwhile host, and without a thought of succor forthe man in whom, for aught he knew, life stillremained, he bolted for the passageway and safety.

But his renewed hopes were soon dashed. Just beyondthe doorway he found the passage completely clogged andchoked by impenetrable masses of shattered rock.Once more he turned and re-entered the treasure vault.Taking the candle from its place he commenced asystematic search of the apartment, nor had he gone farbefore he discovered another door in the opposite endof the room, a door which gave upon creaking hinges tothe weight of his body. Beyond the door lay anothernarrow passageway. Along this Werper made his way,ascending a flight of stone steps to another corridortwenty feet above the level of the first. Theflickering candle lighted the way before him, and amoment later he was thankful for the possession of thiscrude and antiquated luminant, which, a few hoursbefore he might have looked upon with contempt, for itshowed him, just in time, a yawning pit, apparentlyterminating the tunnel he was traversing.

Before him was a circular shaft. He held the candleabove it and peered downward. Below him, at a greatdistance, he saw the light reflected back from thesurface of a pool of water. He had come upon a well.He raised the candle above his head and peered acrossthe black void, and there upon the opposite side he sawthe continuation of the tunnel; but how was he to spanthe gulf?

As he stood there measuring the distance to theopposite side and wondering if he dared venture sogreat a leap, there broke suddenly upon his startledears a piercing scream which diminished gradually untilit ended in a series of dismal moans. The voice seemedpartly human, yet so hideous that it might well haveemanated from the tortured throat of a lost soul,writhing in the fires of hell.

The Belgian shuddered and looked fearfully upward,for the scream had seemed to come from above him.As he looked he saw an opening far overhead, and apatch of sky pinked with brilliant stars.

His half-formed intention to call for help was expungedby the terrifying cry--where such a voice lived, nohuman creatures could dwell. He dared not revealhimself to whatever inhabitants dwelt in the placeabove him. He cursed himself for a fool that he hadever embarked upon such a mission. He wished himselfsafely back in the camp of Achmet Zek, and would almosthave embraced an opportunity to give himself up to themilitary authorities of the Congo if by so doing hemight be rescued from the frightful predicament inwhich he now was.

He listened fearfully, but the cry was not repeated,and at last spurred to desperate means, he gatheredhimself for the leap across the chasm. Going backtwenty paces, he took a running start, and at the edgeof the well, leaped upward and outward in an attempt togain the opposite side.

In his hand he clutched the sputtering candle,and as he took the leap the rush of air extinguished it.In utter darkness he flew through space, clutching outwardfor a hold should his feet miss the invisible ledge.

He struck the edge of the door of the opposite terminusof the rocky tunnel with his knees, slipped backward,clutched desperately for a moment, and at last hunghalf within and half without the opening; but he was safe.For several minutes he dared not move; butclung, weak and sweating, where he lay. At last,cautiously, he drew himself well within the tunnel,and again he lay at full length upon the floor,fighting to regain control of his shattered nerves.

When his knees struck the edge of the tunnel he haddropped the candle. Presently, hoping against hopethat it had fallen upon the floor of the passageway,rather than back into the depths of the well, he roseupon all fours and commenced a diligent search for thelittle tallow cylinder, which now seemed infinitelymore precious to him than all the fabulous wealth ofthe hoarded ingots of Opar.

And when, at last, he found it, he clasped it to himand sank back sobbing and exhausted. For many minuteshe lay trembling and broken; but finally he drewhimself to a sitting posture, and taking a match fromhis pocket, lighted the stump of the candle whichremained to him. With the light he found it easier toregain control of his nerves, and presently he wasagain making his way along the tunnel in search of anavenue of escape. The horrid cry that had come down tohim from above through the ancient well-shaft stillhaunted him, so that he trembled in terror at even thesounds of his own cautious advance.

He had gone forward but a short distance, when, to hischagrin, a wall of masonry barred his farther progress,closing the tunnel completely from top to bottom andfrom side to side. What could it mean? Werper was aneducated and intelligent man. His military traininghad taught him to use his mind for the purpose forwhich it was intended. A blind tunnel such as this wassenseless. It must continue beyond the wall. Someone,at some time in the past, had had it blocked for anunknown purpose of his own. The man fell to examiningthe masonry by the light of his candle. To his delighthe discovered that the thin blocks of hewn stone ofwhich it was constructed were fitted in loosely withoutmortar or cement. He tugged upon one of them, and tohis joy found that it was easily removable. One afteranother he pulled out the blocks until he had opened anaperture large enough to admit his body, then hecrawled through into a large, low chamber. Across thisanother door barred his way; but this, too, gave beforehis efforts, for it was not barred. A long, darkcorridor showed before him, but before he had followedit far, his candle burned down until it scorched hisfingers. With an oath he dropped it to the floor,where it sputtered for a moment and went out.

Now he was in total darkness, and again terror rodeheavily astride his neck. What further pitfalls anddangers lay ahead he could not guess; but that he wasas far as ever from liberty he was quite willing tobelieve, so depressing is utter absence of light to onein unfamiliar surroundings.

Slowly he groped his way along, feeling with his handsupon the tunnel's walls, and cautiously with his feetahead of him upon the floor before he could take asingle forward step. How long he crept on thus hecould not guess; but at last, feeling that the tunnel'slength was interminable, and exhausted by his efforts,by terror, and loss of sleep, he determined to lie downand rest before proceeding farther.

When he awoke there was no change in the surroundingblackness. He might have slept a second or a day--hecould not know; but that he had slept for some time wasattested by the fact that he felt refreshed and hungry.

Again he commenced his groping advance; but this timehe had gone but a short distance when he emerged into aroom, which was lighted through an opening in theceiling, from which a flight of concrete steps leddownward to the floor of the chamber.

Above him, through the aperture, Werper could seesunlight glancing from massive columns, which weretwined about by clinging vines. He listened; but heheard no sound other than the soughing of the windthrough leafy branches, the hoarse cries of birds,and the chattering of monkeys.

Boldly he ascended the stairway, to find himself in acircular court. Just before him stood a stone altar,stained with rusty-brown discolorations. At the timeWerper gave no thought to an explanation of thesestains--later their origin became all too hideouslyapparent to him.

Beside the opening in the floor, just behind the altar,through which he had entered the court from thesubterranean chamber below, the Belgian discoveredseveral doors leading from the enclosure upon the levelof the floor. Above, and circling the courtyard, was aseries of open balconies. Monkeys scampered about thedeserted ruins, and gaily plumaged birds flitted in andout among the columns and the galleries far above; butno sign of human presence was discernible. Werper feltrelieved. He sighed, as though a great weight had beenlifted from his shoulders. He took a step toward oneof the exits, and then he halted, wide-eyed inastonishment and terror, for almost at the same instanta dozen doors opened in the courtyard wall and a hordeof frightful men rushed in upon him.

They were the priests of the Flaming God of Opar--thesame, shaggy, knotted, hideous little men who haddragged Jane Clayton to the sacrificial altar at thisvery spot years before. Their long arms, their shortand crooked legs, their close-set, evil eyes, and theirlow, receding foreheads gave them a bestial appearancethat sent a qualm of paralyzing fright through theshaken nerves of the Belgian.

With a scream he turned to flee back into the lesserterrors of the gloomy corridors and apartments fromwhich he had just emerged, but the frightful menanticipated his intentions. They blocked the way;they seized him, and though he fell, groveling upon hisknees before them, begging for his life, they bound himand hurled him to the floor of the inner temple.

The rest was but a repetition of what Tarzan and JaneClayton had passed through. The priestesses came,and with them La, the High Priestess. Werper was raisedand laid across the altar. Cold sweat exuded from hisevery pore as La raised the cruel, sacrificial knifeabove him. The death chant fell upon his torturedears. His staring eyes wandered to the golden gobletsfrom which the hideous votaries would soon quench theirinhuman thirst in his own, warm life-blood.

He wished that he might be granted the brief respite ofunconsciousness before the final plunge of the keenblade--and then there was a frightful roar that soundedalmost in his ears. The High Priestess lowered herdagger. Her eyes went wide in horror. Thepriestesses, her votaresses, screamed and fled madlytoward the exits. The priests roared out their rageand terror according to the temper of their courage.Werper strained his neck about to catch a sight of thecause of their panic, and when, at last he saw it, hetoo went cold in dread, for what his eyes beheld wasthe figure of a huge lion standing in the center of thetemple, and already a single victim lay mangled beneathhis cruel paws.

Again the lord of the wilderness roared, turning hisbaleful gaze upon the altar. La staggered forward,reeled, and fell across Werper in a swoon.