When the light of day broke upon the little craft towhose deck the Princess of Ptarth had been snatchedfrom her father's garden, Thuvia saw that the night hadwrought a change in her abductors.

No longer did their trappings gleam with the metal of Dusar,but instead there was emblazoned there the insignia of thePrince of Helium.

The girl felt renewed hope, for she could not believe thatin the heart of Carthoris could lie intent to harm her.

She spoke to the warrior squatting before the control board.

"Last night you wore the trappings of a Dusarian,"she said. "Now your metal is that of Helium.What means it?"

The man looked at her with a grin.

"The Prince of Helium is no fool," he said.

Just then an officer emerged from the tiny cabin. Hereprimanded the warrior for conversing with the prisoner,nor would he himself reply to any of her inquiries.

No harm was offered her during the journey, and sothey came at last to their destination with the girl nowiser as to her abductors or their purpose than at first.

Here the flier settled slowly into the plaza of one ofthose mute monuments of Mars' dead and forgotten past--the deserted cities that fringe the sad ochre sea-bottomswhere once rolled the mighty floods upon whose bosoms movedthe maritime commerce of the peoples that are gone for ever.

Thuvia of Ptarth was no stranger to such places.During her wanderings in search of the River Iss,that time she had set out upon what, for countless ages,had been the last, long pilgrimage of Martians, towardthe Valley Dor, where lies the Lost Sea of Korus,she had encountered several of these sad remindersof the greatness and the glory of ancient Barsoom.

And again, during her flight from the temples of theHoly Therns with Tars Tarkas, Jeddak of Thark, she hadseen them, with their weird and ghostly inmates, thegreat white apes of Barsoom.

She knew, too, that many of them were used now bythe nomadic tribes of green men, but that among themall was no city that the red men did not shun, for withoutexception they stood amidst vast, waterless tracts,unsuited for the continued sustenance of the dominantrace of Martians.

Why, then, should they be bringing her to such a place?There was but a single answer. Such was the natureof their work that they must needs seek the seclusionthat a dead city afforded. The girl trembled at thoughtof her plight.

For two days her captors kept her within a huge palacethat even in decay reflected the splendour of the agewhich its youth had known.

Just before dawn on the third day she had been arousedby the voices of two of her abductors.

"He should be here by dawn," one was saying. "Have herin readiness upon the plaza--else he will never land.The moment he finds that he is in a strange countryhe will turn about--methinks the prince's plan is weakin this one spot."

"There was no other way," replied the other. "It iswondrous work to get them both here at all, and evenif we do not succeed in luring him to the ground,we shall have accomplished much."

Just then the speaker caught the eyes of Thuvia upon him,revealed by the quick-moving patch of light cast by Thuriain her mad race through the heavens.

With a quick sign to the other, he ceased speaking,and advancing toward the girl, motioned her to rise. Then he led her out into the night toward the centreof the great plaza.

"Stand here," he commanded, "until we come for you. We shall be watching, and should you attempt to escapeit will go ill with you--much worse than death.Such are the prince's orders."

Then he turned and retraced his steps toward the palace,leaving her alone in the midst of the unseen terrors ofthe haunted city, for in truth these places are hauntedin the belief of many Martians who still cling to an ancientsuperstition which teaches that the spirits of Holy Thernswho die before their allotted one thousand years, pass,on occasions, into the bodies of the great white apes.

To Thuvia, however, the real danger of attack by oneof these ferocious, manlike beasts was quite sufficient. She no longer believed in the weird soul transmigrationthat the therns had taught her before she was rescuedfrom their clutches by John Carter; but she well knew thehorrid fate that awaited her should one of the terriblebeasts chance to spy her during its nocturnal prowlings.

What was that?

Surely she could not be mistaken. Something had moved,stealthily, in the shadow of one of the great monolithsthat line the avenue where it entered the plaza opposite her!

Thar Ban, jed among the hordes of Torquas, rodeswiftly across the ochre vegetation of the dead sea-bottom toward the ruins of ancient Aaanthor.

He had ridden far that night, and fast, for he had butcome from the despoiling of the incubator of a neighbouringgreen horde with which the hordes of Torquas wereperpetually warring.

His giant thoat was far from jaded, yet it would bewell, thought Thar Ban, to permit him to graze uponthe ochre moss which grows to greater height within theprotected courtyards of deserted cities, where the soil isricher than on the sea-bottoms, and the plants partlyshaded from the sun during the cloudless Martian day.

Within the tiny stems of this dry-seeming plant issufficient moisture for the needs of the huge bodies ofthe mighty thoats, which can exist for months withoutwater, and for days without even the slight moisturewhich the ochre moss contains.

As Thar Ban rode noiselessly up the broad avenuewhich leads from the quays of Aaanthor to the greatcentral plaza, he and his mount might have been mistakenfor spectres from a world of dreams, so grotesque the manand beast, so soundless the great thoat's padded, naillessfeet upon the moss-grown flagging of the ancient pavement.

The man was a splendid specimen of his race. Fullyfifteen feet towered his great height from sole to pate.The moonlight glistened against his glossy green hide,sparkling the jewels of his heavy harness and the ornamentsthat weighted his four muscular arms, while theupcurving tusks that protruded from his lower jawgleamed white and terrible.

At the side of his thoat were slung his long radiumrifle and his great, forty-foot, metal-shod spear, whilefrom his own harness depended his long-sword and hisshort-sword, as well as his lesser weapons.

His protruding eyes and antennae-like ears were turningconstantly hither and thither, for Thar Ban was yetin the country of the enemy, and, too, there was alwaysthe menace of the great white apes, which, John Carterwas wont to say, are the only creatures that can arousein the breasts of these fierce denizens of the deadsea-bottoms even the remotest semblance of fear.

As the rider neared the plaza, he reined suddenly in.His slender, tubular ears pointed rigidly forward.An unwonted sound had reached them. Voices! And wherethere were voices, outside of Torquas, there, too,were enemies. All the world of wide Barsoom containednaught but enemies for the fierce Torquasians.

Thar Ban dismounted. Keeping in the shadows of thegreat monoliths that line the Avenue of Quays of sleepingAaanthor, he approached the plaza. Directly behind him,as a hound at heel, came the slate-grey thoat, his whitebelly shadowed by his barrel, his vivid yellow feet merginginto the yellow of the moss beneath them.

In the centre of the plaza Thar Ban saw the figureof a red woman. A red warrior was conversing withher. Now the man turned and retraced his steps towardthe palace at the opposite side of the plaza.

Thar Ban watched until he had disappeared withinthe yawning portal. Here was a captive worth having!Seldom did a female of their hereditary enemies fall tothe lot of a green man. Thar Ban licked his thin lips.

Thuvia of Ptarth watched the shadow behind the monolith atthe opening to the avenue opposite her. She hoped that itmight be but the figment of an overwrought imagination.

But no! Now, clearly and distinctly, she saw it move.It came from behind the screening shelter of the ersite shaft.

The sudden light of the rising sun fell upon it.The girl trembled. The THING was a huge green warrior!

Swiftly it sprang toward her. She screamed and triedto flee; but she had scarce turned toward the palace whena giant hand fell upon her arm, she was whirled about,and half dragged, half carried toward a huge thoatthat was slowly grazing out of the avenue's mouthon to the ochre moss of the plaza.

At the same instant she turned her face upward towardthe whirring sound of something above her, and thereshe saw a swift flier dropping toward her, the headand shoulders of a man leaning far over the side;but the man's features were deeply shadowed, so thatshe did not recognize them.

Now from behind her came the shouts of her red abductors.They were racing madly after him who dared to steal whatthey already had stolen.

As Thar Ban reached the side of his mount he snatchedhis long radium rifle from its boot, and, wheeling,poured three shots into the oncoming red men.

Such is the uncanny marksmanship of these Martiansavages that three red warriors dropped in their tracksas three projectiles exploded in their vitals.

The others halted, nor did they dare return the firefor fear of wounding the girl.

Then Thar Ban vaulted to the back of his thoat, Thuvia of Ptarthstill in his arms, and with a savage cry of triumph disappeareddown the black canyon of the Avenue of Quays between the sullenpalaces of forgotten Aaanthor.

Carthoris' flier had not touched the ground before hehad sprung from its deck to race after the swift thoat,whose eight long legs were sending it down the avenueat the rate of an express train; but the men of Dusarwho still remained alive had no mind to permit so valuablea capture to escape them.

They had lost the girl. That would be a difficult thingto explain to Astok; but some leniency might be expectedcould they carry the Prince of Helium to theirmaster instead.

So the three who remained set upon Carthoris withtheir long-swords, crying to him to surrender; but theymight as successfully have cried aloud to Thuria tocease her mad hurtling through the Barsoomian sky, forCarthoris of Helium was a true son of the Warlord of Marsand his incomparable Dejah Thoris.

Carthoris' long-sword had been already in his handas he leaped from the deck of the flier, so the instantthat he realized the menace of the three red warriors,he wheeled to face them, meeting their onslaught as onlyJohn Carter himself might have done.

So swift his sword, so mighty and agile his half-earthlymuscles, that one of his opponents was down, crimsoningthe ochre moss with his life-blood, when he had scarcemade a single pass at Carthoris.

Now the two remaining Dusarians rushed simultaneouslyupon the Heliumite. Three long-swords clashed andsparkled in the moonlight, until the great white apes,roused from their slumbers, crept to the lowering windowsof the dead city to view the bloody scene beneath them.

Thrice was Carthoris touched, so that the red bloodran down his face, blinding him and dyeing his broadchest. With his free hand he wiped the gore from hiseyes, and with the fighting smile of his father touchinghis lips, leaped upon his antagonists with renewed fury.

A single cut of his heavy sword severed the head ofone of them, and then the other, backing away clear ofthat point of death, turned and fled toward the palaceat his back.

Carthoris made no step to pursue. He had other concernthan the meting of even well-deserved punishment to strangemen who masqueraded in the metal of his own house,for he had seen that these men were tricked out inthe insignia that marked his personal followers.

Turning quickly toward his flier, he was soon risingfrom the plaza in pursuit of Thar Ban.

The red warrior whom he had put to flight turned in theentrance to the palace, and, seeing Carthoris' intent,snatched a rifle from those that he and his fellowshad left leaning against the wall as they had rushed outwith drawn swords to prevent the theft of their prisoner.

Few red men are good shots, for the sword is theirchosen weapon; so now as the Dusarian drew bead uponthe rising flier, and touched the button upon his rifle'sstock, it was more to chance than proficiency that heowed the partial success of his aim.

The projectile grazed the flier's side, the opaquecoating breaking sufficiently to permit daylight tostrike in upon the powder phial within the bullet's nose.There was a sharp explosion. Carthoris felt his craft reeldrunkenly beneath him, and the engine stopped.

The momentum the air boat had gained carried her onover the city toward the sea-bottom beyond.

The red warrior in the plaza fired several more shots,none of which scored. Then a lofty minaret shut thedrifting quarry from his view.

In the distance before him Carthoris could see thegreen warrior bearing Thuvia of Ptarth away upon hismighty thoat. The direction of his flight was towardthe north-west of Aaanthor, where lay a mountainouscountry little known to red men.

The Heliumite now gave his attention to his injured craft.A close examination revealed the face that one of thebuoyancy tanks had been punctured, but the engineitself was uninjured.

A splinter from the projectile had damaged one ofthe control levers beyond the possibility of repairoutside a machine shop; but after considerable tinkering,Carthoris was able to propel his wounded flier at lowspeed, a rate which could not approach the rapid gaitof the thoat, whose eight long, powerful legs carried itover the ochre vegetation of the dead sea-bottom atterrific speed.

The Prince of Helium chafed and fretted at the slownessof his pursuit, yet he was thankful that the damagewas no worse, for now he could at least move morerapidly than on foot.

But even this meagre satisfaction was soon to be deniedhim, for presently the flier commenced to sag towardthe port and by the bow. The damage to the buoyancytanks had evidently been more grievous than he had atfirst believed.

All the balance of that long day Carthoris crawlederratically through the still air, the bow of the fliersinking lower and lower, and the list to port becoming moreand more alarming, until at last, near dark, he was floatingalmost bowdown, his harness buckled to a heavydeck ring to keep him from being precipitated to theground below.

His forward movement was now confined to a slow driftingwith the gentle breeze that blew out of the south-east,and when this died down with the setting of the sun,he let the flier sink gently to the mossy carpet beneath.

Far before him loomed the mountains toward whichthe green man had been fleeing when last he had seenhim, and with dogged resolution the son of John Carter,endowed with the indomitable will of his mighty sire,took up the pursuit on foot.

All that night he forged ahead until, with the dawningof a new day, he entered the low foothills that guardthe approach to the fastness of the mountains of Torquas.

Rugged, granitic walls towered before him. Nowherecould he discern an opening through the formidablebarrier; yet somewhere into this inhospitable worldof stone the green warrior had borne the woman ofthe red man's heart's desire.

Across the yielding moss of the sea-bottom there hadbeen no spoor to follow, for the soft pads of the thoatbut pressed down in his swift passage the resilientvegetation which sprang up again behind his fleetingfeet, leaving no sign.

But here in the hills, where loose rock occasionallystrewed the way; where black loam and wild flowerspartially replaced the sombre monotony of the wasteplaces of the lowlands, Carthoris hoped to find somesign that would lead him in the right direction.

Yet, search as he would, the baffling mystery of thetrail seemed likely to remain for ever unsolved.

It was drawing toward the day's close once more whenthe keen eyes of the Heliumite discerned the tawnyyellow of a sleek hide moving among the bouldersseveral hundred yards to his left.

Crouching quickly behind a large rock, Carthoriswatched the thing before him. It was a huge banth,one of those savage Barsoomian lions that roam thedesolate hills of the dying planet.

The creature's nose was close to the ground. It wasevident that he was following the spoor of meat by scent.

As Carthoris watched him, a great hope leaped intothe man's heart. Here, possibly, might lie the solutionto the mystery he had been endeavouring to solve. Thishungry carnivore, keen always for the flesh of man,might even now be trailing the two whom Carthoris sought.

Cautiously the youth crept out upon the trail of theman-eater. Along the foot of the perpendicular cliff thecreature moved, sniffing at the invisible spoor, and nowand then emitting the low moan of the hunting banth.

Carthoris had followed the creature for but a fewminutes when it disappeared as suddenly and mysteriouslyas though dissolved into thin air.

The man leaped to his feet. Not again was he to becheated as the man had cheated him. He sprang forwardat a reckless pace to the spot at which he last hadseen the great, skulking brute.

Before him loomed the sheer cliff, its face unbrokenby any aperture into which the huge banth might havewormed its great carcass. Beside him was a small, flatboulder, not larger than the deck of a ten-man flier, norstanding to a greater height than twice his own stature.

Perhaps the banth was in hiding behind this? The brutemight have discovered the man upon his trail, and evennow be lying in wait for his easy prey.

Cautiously, with drawn long-sword, Carthoris creptaround the corner of the rock. There was no banththere, but something which surprised him infinitely morethan would the presence of twenty banths.

Before him yawned the mouth of a dark cave leadingdownward into the ground. Through this the banth musthave disappeared. Was it his lair? Within its dark andforbidding interior might there not lurk not one but manyof the fearsome creatures?

Carthoris did not know, nor, with the thought that hadbeen spurring him onward upon the trail of the creatureuppermost in his mind, did he much care; for into thisgloomy cavern he was sure the banth had trailed thegreen man and his captive, and into it he, too, wouldfollow, content to give his life in the service of thewoman he loved.

Not an instant did he hesitate, nor yet did headvance rashly; but with ready sword and cautious steps,for the way was dark, he stole on. As he advanced,the obscurity became impenetrable blackness.