How long I slept upon the floor of the storeroom I do notknow, but it must have been many hours.

I was awakened with a start by cries of alarm, and scarcewere my eyes opened, nor had I yet sufficiently collected mywits to quite realize where I was, when a fusillade of shotsrang out, reverberating through the subterranean corridors ina series of deafening echoes.

In an instant I was upon my feet. A dozen lesser thernsconfronted us from a large doorway at the opposite end ofthe storeroom from which we had entered. About me lay thebodies of my companions, with the exception of Thuvia andTars Tarkas, who, like myself, had been asleep upon the floorand thus escaped the first raking fire.

As I gained my feet the therns lowered their wicked rifles, theirfaces distorted in mingled chagrin, consternation, and alarm.

Instantly I rose to the occasion.

"What means this?" I cried in tones of fierce anger. "Is Sator Throgto be murdered by his own vassals?"

"Have mercy, O Master of the Tenth Cycle!" cried one ofthe fellows, while the others edged toward the doorway asthough to attempt a surreptitious escape from the presenceof the mighty one.

"Ask them their mission here," whispered Thuvia at my elbow.

"What do you here, fellows?" I cried.

"Two from the outer world are at large within the dominionsof the therns. We sought them at the command of the Fatherof Therns. One was white with black hair, the other ahuge green warrior," and here the fellow cast a suspiciousglance toward Tars Tarkas.

"Here, then, is one of them," spoke Thuvia, indicating theThark, "and if you will look upon this dead man by the doorperhaps you will recognize the other. It was left for SatorThrog and his poor slaves to accomplish what the lessertherns of the guard were unable to do--we have killed oneand captured the other; for this had Sator Throg given usour liberty. And now in your stupidity have you come andkilled all but myself, and like to have killed the mightySator Throg himself."

The men looked very sheepish and very scared.

"Had they not better throw these bodies to the plant menand then return to their quarters, O Mighty One?" askedThuvia of me.

"Yes; do as Thuvia bids you," I said.

As the men picked up the bodies I noticed that the onewho stooped to gather up the late Sator Throg started as hiscloser scrutiny fell upon the upturned face, and then thefellow stole a furtive, sneaking glance in my direction fromthe corner of his eye.

That he suspicioned something of the truth I could have sworn;but that it was only a suspicion which he did not dare voice wasevidenced by his silence.

Again, as he bore the body from the room, he shot a quickbut searching glance toward me, and then his eyes fell oncemore upon the bald and shiny dome of the dead man in hisarms. The last fleeting glimpse that I obtained of his profileas he passed from my sight without the chamber revealed acunning smile of triumph upon his lips.

Only Tars Tarkas, Thuvia, and I were left. The fatalmarksmanship of the therns had snatched from our companionswhatever slender chance they had of gaining the perilousfreedom of the world without.

So soon as the last of the gruesome procession had disappearedthe girl urged us to take up our flight once more.

She, too, had noted the questioning attitude of the thernwho had borne Sator Throg away.

"It bodes no good for us, O Prince," she said. "For eventhough this fellow dared not chance accusing you in error,there be those above with power sufficient to demand a closerscrutiny, and that, Prince would indeed prove fatal."

I shrugged my shoulders. It seemed that in any event theoutcome of our plight must end in death. I was refreshed frommy sleep, but still weak from loss of blood. My wounds werepainful. No medicinal aid seemed possible. How I longedfor the almost miraculous healing power of the strange salvesand lotions of the green Martian women. In an hour theywould have had me as new.

I was discouraged. Never had a feeling of such utter hopelessnesscome over me in the face of danger. Then the long flowing, yellowlocks of the Holy Thern, caught by some vagrant draught, blewabout my face.

Might they not still open the way of freedom? If we actedin time, might we not even yet escape before the generalalarm was sounded? We could at least try.

"What will the fellow do first, Thuvia?" I asked. "How longwill it be before they may return for us?"

"He will go directly to the Father of Therns, old MataiShang. He may have to wait for an audience, but since he isvery high among the lesser therns, in fact as a thorian amongthem, it will not be long that Matai Shang will keep him waiting.

"Then if the Father of Therns puts credence in his story,another hour will see the galleries and chambers, the courtsand gardens, filled with searchers."

"What we do then must be done within an hour. What is thebest way, Thuvia, the shortest way out of this celestial Hades?"

"Straight to the top of the cliffs, Prince," she replied, "andthen through the gardens to the inner courts. From there ourway will lie within the temples of the therns and across them tothe outer court. Then the ramparts--O Prince, it is hopeless. Ten thousand warriors could not hew a way to liberty from outthis awful place.

"Since the beginning of time, little by little, stone by stone,have the therns been ever adding to the defences of theirstronghold. A continuous line of impregnable fortificationscircles the outer slopes of the Mountains of Otz.

"Within the temples that lie behind the ramparts a millionfighting-men are ever ready. The courts and gardens arefilled with slaves, with women and with children.

"None could go a stone's throw without detection."

"If there is no other way, Thuvia, why dwell upon thedifficulties of this. We must face them."

"Can we not better make the attempt after dark?" askedTars Tarkas. "There would seem to be no chance by day."

"There would be a little better chance by night, but eventhen the ramparts are well guarded; possibly better than byday. There are fewer abroad in the courts and gardens,though," said Thuvia.

"What is the hour?" I asked.

"It was midnight when you released me from my chains,"said Thuvia. "Two hours later we reached the storeroom.There you slept for fourteen hours. It must now be nearlysundown again. Come, we will go to some nearby window inthe cliff and make sure."

So saying, she led the way through winding corridorsuntil at a sudden turn we came upon an opening whichoverlooked the Valley Dor.

At our right the sun was setting, a huge red orb, below thewestern range of Otz. A little below us stood the Holy Thernon watch upon his balcony. His scarlet robe of office waspulled tightly about him in anticipation of the cold that comesso suddenly with darkness as the sun sets. So rare is theatmosphere of Mars that it absorbs very little heat from thesun. During the daylight hours it is always extremely hot; atnight it is intensely cold. Nor does the thin atmosphererefract the sun's rays or diffuse its light as upon Earth.There is no twilight on Mars. When the great orb of day disappearsbeneath the horizon the effect is precisely as that of theextinguishing of a single lamp within a chamber. From brilliantlight you are plunged without warning into utter darkness. Then the moons come; the mysterious, magic moons of Mars,hurtling like monster meteors low across the face of the planet.

The declining sun lighted brilliantly the eastern banks ofKorus, the crimson sward, the gorgeous forest. Beneath thetrees we saw feeding many herds of plant men. The adultsstood aloft upon their toes and their mighty tails, their talonspruning every available leaf and twig. It was then that Iunderstood the careful trimming of the trees which had ledme to form the mistaken idea when first I opened my eyes uponthe grove that it was the playground of a civilized people.

As we watched, our eyes wandered to the rolling Iss,which issued from the base of the cliffs beneath us.Presently there emerged from the mountain a canoe laden withlost souls from the outer world. There were a dozen of them.All were of the highly civilized and cultured race of red menwho are dominant on Mars.

The eyes of the herald upon the balcony beneath us fellupon the doomed party as soon as did ours. He raised hishead and leaning far out over the low rail that rimmed hisdizzy perch, voiced the shrill, weird wail that called thedemons of this hellish place to the attack.

For an instant the brutes stood with stiffly erected ears, thenthey poured from the grove toward the river's bank, coveringthe distance with great, ungainly leaps.

The party had landed and was standing on the sward asthe awful horde came in sight. There was a brief and futileeffort of defence. Then silence as the huge, repulsive shapescovered the bodies of their victims and scores of suckingmouths fastened themselves to the flesh of their prey.

I turned away in disgust.

"Their part is soon over," said Thuvia. "The great white apesget the flesh when the plant men have drained the arteries. Look, they are coming now."

As I turned my eyes in the direction the girl indicated, Isaw a dozen of the great white monsters running across thevalley toward the river bank. Then the sun went down anddarkness that could almost be felt engulfed us.

Thuvia lost no time in leading us toward the corridorwhich winds back and forth up through the cliffs toward thesurface thousands of feet above the level on which we had been.

Twice great banths, wandering loose through the galleries,blocked our progress, but in each instance Thuvia spoke a lowword of command and the snarling beasts slunk sullenly away.

"If you can dissolve all our obstacles as easily as youmaster these fierce brutes I can see no difficulties in our way,"I said to the girl, smiling. "How do you do it?"

She laughed, and then shuddered.

"I do not quite know," she said. "When first I came here Iangered Sator Throg, because I repulsed him. He ordered meto be thrown into one of the great pits in the inner gardens.It was filled with banths. In my own country I had beenaccustomed to command. Something in my voice, I do notknow what, cowed the beasts as they sprang to attack me.

"Instead of tearing me to pieces, as Sator Throg haddesired, they fawned at my feet. So greatly were Sator Throgand his friends amused by the sight that they kept me to trainand handle the terrible creatures. I know them all by name.There are many of them wandering through these lower regions.They are the scavengers. Many prisoners die here in their chains.The banths solve the problem of sanitation, at least in this respect.

"In the gardens and temples above they are kept in pits.The therns fear them. It is because of the banths that theyseldom venture below ground except as their duties call them."

An idea occurred to me, suggested by what Thuvia had just said.

"Why not take a number of banths and set them loose before usabove ground?" I asked.

Thuvia laughed.

"It would distract attention from us, I am sure," she said.

She commenced calling in a low singsong voice that washalf purr. She continued this as we wound our tedious waythrough the maze of subterranean passages and chambers.

Presently soft, padded feet sounded close behind us, andas I turned I saw a pair of great, green eyes shining in thedark shadows at our rear. From a diverging tunnel a sinuous,tawny form crept stealthily toward us.

Low growls and angry snarls assailed our ears on everyside as we hastened on and one by one the ferociouscreatures answered the call of their mistress.

She spoke a word to each as it joined us. Like well-schooled terriers, they paced the corridors with us, but Icould not help but note the lathering jowls, nor the hungryexpressions with which they eyed Tars Tarkas and myself.

Soon we were entirely surrounded by some fifty of thebrutes. Two walked close on either side of Thuvia, as guardsmight walk. The sleek sides of others now and then touchedmy own naked limbs. It was a strange experience; thealmost noiseless passage of naked human feet and paddedpaws; the golden walls splashed with precious stones; thedim light cast by the tiny radium bulbs set at considerabledistances along the roof; the huge, maned beasts of preycrowding with low growls about us; the mighty green warriortowering high above us all; myself crowned with the pricelessdiadem of a Holy Thern; and leading the procession thebeautiful girl, Thuvia.

I shall not soon forget it.

Presently we approached a great chamber more brightlylighted than the corridors. Thuvia halted us. Quietly shestole toward the entrance and glanced within. Then shemotioned us to follow her.

The room was filled with specimens of the strange beingsthat inhabit this underworld; a heterogeneous collection ofhybrids--the offspring of the prisoners from the outsideworld; red and green Martians and the white race of therns.

Constant confinement below ground had wrought odd freaksupon their skins. They more resemble corpses than livingbeings. Many are deformed, others maimed, while themajority, Thuvia explained, are sightless.

As they lay sprawled about the floor, sometimes overlappingone another, again in heaps of several bodies, they suggestedinstantly to me the grotesque illustrations that I hadseen in copies of Dante's INFERNO, and what more fittingcomparison? Was this not indeed a veritable hell, peopledby lost souls, dead and damned beyond all hope?

Picking our way carefully we threaded a winding pathacross the chamber, the great banths sniffing hungrily atthe tempting prey spread before them in such tantalizing anddefenceless profusion.

Several times we passed the entrances to other chambers similarlypeopled, and twice again we were compelled to cross directlythrough them. In others were chained prisoners and beasts.

"Why is it that we see no therns?" I asked of Thuvia.

"They seldom traverse the underworld at night, forthen it is that the great banths prowl the dim corridorsseeking their prey. The therns fear the awful denizens ofthis cruel and hopeless world that they have fostered and allowedto grow beneath their feet. The prisoners even sometimes turnupon them and rend them. The thern can never tell fromwhat dark shadow an assassin may spring upon his back.

"By day it is different. Then the corridors and chambersare filled with guards passing to and fro; slaves from thetemples above come by hundreds to the granaries andstorerooms. All is life then. You did not see it because I ledyou not in the beaten tracks, but through roundabout passagesseldom used. Yet it is possible that we may meet a thern even yet.They do occasionally find it necessary to come here after the sun has set.Because of this I have moved with such great caution."

But we reached the upper galleries without detection andpresently Thuvia halted us at the foot of a short, steep ascent.

"Above us," she said, "is a doorway which opens on tothe inner gardens. I have brought you thus far. From hereon for four miles to the outer ramparts our way will be besetby countless dangers. Guards patrol the courts, the temples,the gardens. Every inch of the ramparts themselves isbeneath the eye of a sentry."

I could not understand the necessity for such an enormousforce of armed men about a spot so surrounded by mysteryand superstition that not a soul upon Barsoom would havedared to approach it even had they known its exact location.I questioned Thuvia, asking her what enemies the therns couldfear in their impregnable fortress.

We had reached the doorway now and Thuvia was opening it.

"They fear the black pirates of Barsoom, O Prince," shesaid, "from whom may our first ancestors preserve us."

The door swung open; the smell of growing things greetedmy nostrils; the cool night air blew against my cheek. Thegreat banths sniffed the unfamiliar odours, and then with arush they broke past us with low growls, swarming across thegardens beneath the lurid light of the nearer moon.

Suddenly a great cry arose from the roofs of the temples;a cry of alarm and warning that, taken up from point topoint, ran off to the east and to the west, from temple, court,and rampart, until it sounded as a dim echo in the distance.

The great Thark's long-sword leaped from its scabbard;Thuvia shrank shuddering to my side.