The day following the coming of Vas Kor to thepalace of the Prince of Helium great excitement reignedthroughout the twin cities, reaching its climax in thepalace of Carthoris. Word had come of the abduction ofThuvia of Ptarth from her father's court, and with it theveiled hint that the Prince of Helium might be suspectedof considerable knowledge of the act and the whereaboutsof the princess.

In the council chamber of John Carter, Warlord ofMars, was Tardos Mors, Jeddak of Helium; Mors Kajak,his son, Jed of Lesser Helium; Carthoris, and a score ofthe great nobles of the empire.

"There must be no war between Ptarth and Helium, my son,"said John Carter. "That you are innocent of the chargethat has been placed against you by insinuation, we well know;but Thuvan Dihn must know it well, too.

"There is but one who may convince him, and thatone be you. You must hasten at once to the court ofPtarth, and by your presence there as well as by yourwords assure him that his suspicions are groundless. Bear with you the authority of the Warlord of Barsoom,and of the Jeddak of Helium to offer every resource of theallied powers to assist Thuvan Dihn to recover his daughterand punish her abductors, whomsoever they may be.

"Go! I know that I do not need to urge upon you thenecessity for haste."

Carthoris left the council chamber, and hastened to his palace.

Here slaves were busy in a moment setting things torights for the departure of their master. Several workedabout the swift flier that would bear the Prince of Heliumrapidly toward Ptarth.

At last all was done. But two armed slaves remainedon guard. The setting sun hung low above the horizon. In a moment darkness would envelop all.

One of the guardsmen, a giant of a fellow across whoseright cheek there ran a thin scar from temple to mouth,approached his companion. His gaze was directed beyondand above his comrade. When he had come quite close he spoke.

"What strange craft is that?" he asked.

The other turned about quickly to gaze heavenward. Scarce was his back turned toward the giant than theshort-sword of the latter was plunged beneath his leftshoulder blade, straight through his heart.

Voiceless, the soldier sank in his tracks--stone dead. Quickly the murderer dragged the corpse into the blackshadows within the hangar. Then he returned to the flier.

Drawing a cunningly wrought key from his pocket-pouch,he removed the cover of the right-hand dial of thecontrolling destination compass. For a moment hestudied the construction of the mechanism beneath.Then he returned the dial to its place, set the pointer,and removed it again to note the resultant change in theposition of the parts affected by the act.

A smile crossed his lips. With a pair of cutters hesnipped off the projection which extended through thedial from the external pointer--now the latter might bemoved to any point upon the dial without affecting themechanism below. In other words, the eastern hemispheredial was useless.

Now he turned his attention to the western dial.This he set upon a certain point. Afterward he removedthe cover of this dial also, and with keen tool cut thesteel finger from the under side of the pointer.

As quickly as possible he replaced the second dialcover, and resumed his place on guard. To all intentsand purposes the compass was as efficient as before; but,as a matter of fact, the moving of the pointers uponthe dials resulted now in no corresponding shift of themechanism beneath--and the device was set, immovably,upon a destination of the slave's own choosing.

Presently came Carthoris, accompanied by but a handfulof his gentlemen. He cast but a casual glance upon thesingle slave who stood guard. The fellow's thin, cruellips, and the sword-cut that ran from temple to moutharoused the suggestion of an unpleasant memory within him.He wondered where Saran Tal had found the man-- then thematter faded from his thoughts, and in another momentthe Prince of Helium was laughing and chatting withhis companions, though below the surface his heartwas cold with dread, for what contingenciesconfronted Thuvia of Ptarth he could not even guess.

First to his mind, naturally, had sprung the thoughtthat Astok of Dusar had stolen the fair Ptarthian; butalmost simultaneously with the report of the abduction hadcome news of the great fetes at Dusar in honour of thereturn of the jeddak's son to the court of his father.

It could not have been he, thought Carthoris, for on thevery night that Thuvia was taken Astok had been inDusar, and yet--

He entered the flier, exchanging casual remarks with hiscompanions as he unlocked the mechanism of the compassand set the pointer upon the capital city of Ptarth.

With a word of farewell he touched the button whichcontrolled the repulsive rays, and as the flier rose lightlyinto the air, the engine purred in answer to the touch ofhis finger upon a second button, the propellers whirredas his hand drew back the speed lever, and Carthoris,Prince of Helium, was off into the gorgeous Martian nightbeneath the hurtling moons and the million stars.

Scarce had the flier found its speed ere the man,wrapping his sleeping silks and furs about him,stretched at full length upon the narrow deck to sleep.

But sleep did not come at once at his bidding.

Instead, his thoughts ran riot in his brain, driving sleep away.He recalled the words of Thuvia of Ptarth, words that had halfassured him that she loved him; for when he had asked her if sheloved Kulan Tith, she had answered only that she was promised to him.

Now he saw that her reply was open to more than asingle construction. It might, of course, mean thatshe did not love Kulan Tith; and so, by inference,be taken to mean that she loved another.

But what assurance was there that the other was Carthoris of Helium?

The more he thought upon it the more positive hebecame that not only was there no assurance in her wordsthat she loved him, but none either in any act of hers. No, the fact was, she did not love him. She loved another. She had not been abducted--she had fled willingly with her lover.

With such pleasant thoughts filling him alternately withdespair and rage, Carthoris at last dropped into thesleep of utter mental exhaustion.

The breaking of the sudden dawn found him still asleep.His flier was rushing swiftly above a barren, ochreplain--the world-old bottom of a long-dead Martian sea.

In the distance rose low hills. Toward these the craftwas headed. As it approached them, a great promontorymight have been seen from its deck, stretching out intowhat had once been a mighty ocean, and circling backonce more to enclose the forgotten harbour of a forgottencity, which still stretched back from its deserted quays,an imposing pile of wondrous architecture of a long-dead past.

The countless dismal windows, vacant and forlorn,stared, sightless, from their marble walls; the wholesad city taking on the semblance of scattered mounds ofdead men's sun-bleached skulls--the casements having theappearance of eyeless sockets, the portals, grinning jaws.

Closer came the flier, but now its speed wasdiminishing--yet this was not Ptarth.

Above the central plaza it stopped, slowly settling Marsward.Within a hundred yards of the ground it came to rest,floating gently in the light air, and at the same instantan alarm sounded at the sleeper's ear.

Carthoris sprang to his feet. Below him he looked tosee the teeming metropolis of Ptarth. Beside him,already, there should have been an air patrol.

He gazed about in bewildered astonishment. There indeedwas a great city, but it was not Ptarth. No multitudessurged through its broad avenues. No signs of lifebroke the dead monotony of its deserted roof tops.No gorgeous silks, no priceless furs lent life andcolour to the cold marble and the gleaming ersite.

No patrol boat lay ready with its familiar challenge. Silent and empty lay the great city--empty and silentthe surrounding air.

What had happened?

Carthoris examined the dial of his compass. The pointerwas set upon Ptarth. Could the creature of his geniushave thus betrayed him? He would not believe it.

Quickly he unlocked the cover, turning it back uponits hinge. A single glance showed him the truth, or atleast a part of it--the steel projection that communicatedthe movement of the pointer upon the dial to the heartof the mechanism beneath had been severed.

Who could have done the thing--and why?

Carthoris could not hazard even a faint guess. But thething now was to learn in what portion of the world hewas, and then take up his interrupted journey once more.

If it had been the purpose of some enemy to delay him,he had succeeded well, thought Carthoris, as heunlocked the cover of the second dial the first havingshown that its pointer had not been set at all.

Beneath the second dial he found the steel pin severedas in the other, but the controlling mechanism had firstbeen set for a point upon the western hemisphere.

He had just time to judge his location roughly atsome place south-west of Helium, and at a considerabledistance from the twin cities, when he was startled by awoman's scream beneath him.

Leaning over the side of the flier, he saw what appearedto be a red woman being dragged across the plaza by ahuge green warrior--one of those fierce, cruel denizensof the dead sea-bottoms and deserted cities of dying Mars.

Carthoris waited to see no more. Reaching for thecontrol board, he sent his craft racing plummet-liketoward the ground.

The green man was hurrying his captive toward ahuge thoat that browsed upon the ochre vegetation ofthe once scarlet-gorgeous plaza. At the same instant adozen red warriors leaped from the entrance of a nearbyersite palace, pursuing the abductor with naked swordsand shouts of rageful warning.

Once the woman turned her face upward toward the falling flier,and in the single swift glance Carthoris saw that it wasThuvia of Ptarth!