I did not venture out upon the limb for fear that I might be discovered and our retreat in this direction cut off; but instead hurried to retrace my steps to Tars Tarkas.

I soon reached him and presently we were both ascending the long ladder toward the opening above.

Tars Tarkas went in advance and as I reached the first of the horizontal bars I drew the ladder up after me and, handing it to him, he carried it a hundred feet further aloft, where he wedged it safely between one of the bars and the side of the shaft. In like manner I dislodged the lower bars as I passed them, so that we soon had the interior of the tree denuded of all possible means of ascent for a distance of a hundred feet from the base; thus precluding possible pursuit and attack from the rear.

As we were to learn later, this precaution saved us from dire predicament, and was eventually the means of our salvation.

When we reached the opening at the top Tars Tarkas drew to one side that I might pass out and investigate, as, owing to my lesser weight and greater agility, I was better fitted for the perilous threading of this dizzy, hanging pathway.

The limb upon which I found myself ascended at a slight angle toward the cliff, and as I followed it I found that it terminated a few feet above a narrow ledge which protruded from the cliff's face at the entrance to a narrow cave.

As I approached the slightly more slender extremity of the branch it bent beneath my weight until, as I balanced perilously upon its outer tip, it swayed gently on a level with the ledge at a distance of a couple of feet.

Five hundred feet below me lay the vivid scarlet carpet of the valley; nearly five thousand feet above towered the mighty, gleaming face of the gorgeous cliffs.

The cave that I faced was not one of those that I had seen from the ground, and which lay much higher, possibly a thousand feet. But so far as I might know it was as good for our purpose as another, and so I returned to the tree for Tars Tarkas.

Together we wormed our way along the waving pathway, but when we reached the end of the branch we found that our combined weight so depressed the limb that the cave's mouth was now too far above us to be reached.

We finally agreed that Tars Tarkas should return along the branch, leaving his longest leather harness strap with me, and that when the limb had risen to a height that would permit me to enter the cave I was to do so, and on Tars Tarkas' return I could then lower the strap and haul him up to the safety of the ledge.

This we did without mishap and soon found ourselves together upon the verge of a dizzy little balcony, with a magnificent view of the valley spreading out below us.

As far as the eye could reach gorgeous forest and crimson sward skirted a silent sea, and about all towered the brilliant monster guardian cliffs. Once we thought we discerned a gilded minaret gleaming in the sun amidst the waving tops of far-distant trees, but we soon abandoned the idea in the belief that it was but an hallucination born of our great desire to discover the haunts of civilized men in this beautiful, yet forbidding, spot.

Below us upon the river's bank the great white apes were devouring the last remnants of Tars Tarkas' former companions, while great herds of plant men grazed in ever-widening circles about the sward which they kept as close clipped as the smoothest of lawns.

Knowing that attack from the tree was now improbable, we determined to explore the cave, which we had every reason to believe was but a continuation of the path we had already traversed, leading the gods alone knew where, but quite evidently away from this valley of grim ferocity.

As we advanced we found a well-proportioned tunnel cut from the solid cliff. Its walls rose some twenty feet above the floor, which was about five feet in width. The roof was arched. We had no means of making a light, and so groped our way slowly into the ever-increasing darkness, Tars Tarkas keeping in touch with one wall while I felt along the other, while, to prevent our wandering into diverging branches and becoming separated or lost in some intricate and labyrinthine maze, we clasped hands.

How far we traversed the tunnel in this manner I do not know, but presently we came to an obstruction which blocked our further progress. It seemed more like a partition than a sudden ending of the cave, for it was constructed not of the material of the cliff, but of something which felt like very hard wood.

Silently I groped over its surface with my hands, and presently was rewarded by the feel of the button which as commonly denotes a door on Mars as does a door knob on Earth.

Gently pressing it, I had the satisfaction of feeling the door slowly give before me, and in another instant we were looking into a dimly lighted apartment, which, so far as we could see, was unoccupied.

Without more ado I swung the door wide open and, followed by the huge Thark, stepped into the chamber. As we stood for a moment in silence gazing about the room a slight noise behind caused me to turn quickly, when, to my astonishment, I saw the door close with a sharp click as though by an unseen hand.

Instantly I sprang toward it to wrench it open again, for something in the uncanny movement of the thing and the tense and almost palpable silence of the chamber seemed to portend a lurking evil lying hidden in this rock-bound chamber within the bowels of the Golden Cliffs.

My fingers clawed futilely at the unyielding portal, while my eyes sought in vain for a duplicate of the button which had given us ingress. And then, from unseen lips, a cruel and mocking peal of laughter rang through the desolate place.

For moments after that awful laugh had ceased reverberating through the rocky room, Tars Tarkas and I stood in tense and expectant silence. But no further sound broke the stillness, nor within the range of our vision did aught move.

At length Tars Tarkas laughed softly, after the manner of his strange kind when in the presence of the horrible or terrifying. It is not an hysterical laugh, but rather the genuine expression of the pleasure they derive from the things that move Earth men to loathing or to tears.

Often and again have I seen them roll upon the ground in mad fits of uncontrollable mirth when witnessing the death agonies of women and little children beneath the torture of that hellish green Martian fete-the Great Games.

I looked up at the Thark, a smile upon my own lips, for here in truth was greater need for a smiling face than a trembling chin.

"What do you make of it all?" I asked. "Where in the deuce are we?"

He looked at me in surprise.

"Where are we?" he repeated. "Do you tell me, John Carter, that you know not where you be?"

"That I am upon Barsoom is all that I can guess, and but for you and the great white apes I should not even guess that, for the sights I have seen this day are as unlike the things of my beloved Barsoom as I knew it ten long years ago as they are unlike the world of my birth.

"No, Tars Tarkas, I know not where we be."

"Where have you been since you opened the mighty portals of the atmosphere plant years ago, after the keeper had died and the engines stopped and all Barsoom was dying, that had not already died, of asphyxiation? Your body even was never found, though the men of a whole world sought after it for years, though the Jeddak of Helium and his granddaughter, your princess, offered such fabulous rewards that even princes of royal blood joined in the search.

"There was but one conclusion to reach when all efforts to locate you had failed, and that, that you had taken the long, last pilgrimage down the mysterious River Iss, to await in the Valley Dor upon the shores of the Lost Sea of Korus the beautiful Dejah Thoris, your princess.