I did not dare follow him there beneath the moonlight, since it best suited my plans not to interrupt his-I wished him to reach his destination unsuspecting, that I might learn just where that destination lay and the business that awaited the night prowler there.

So it was that I remained hidden until after Thurid had disappeared over the edge of the steep bank beside the sea a quarter of a mile away. Then, with Woola following, I hastened across the open after the black dator.

The quiet of the tomb lay upon the mysterious valley of death, crouching deep in its warm nest within the sunken area at the south pole of the dying planet. In the far distance the Golden Cliffs raised their mighty barrier faces far into the starlit heavens, the precious metals and scintillating jewels that composed them sparkling in the brilliant light of Mars's two gorgeous moons.

At my back was the forest, pruned and trimmed like the sward to parklike symmetry by the browsing of the ghoulish plant men.

Before me lay the Lost Sea of Korus, while farther on I caught the shimmering ribbon of Iss, the River of Mystery, where it wound out from beneath the Golden Cliffs to empty into Korus, to which for countless ages had been borne the deluded and unhappy Martians of the outer world upon the voluntary pilgrimage to this false heaven.

The plant men, with their blood-sucking hands, and the monstrous white apes that make Dor hideous by day, were hidden in their lairs for the night.

There was no longer a Holy Thern upon the balcony in the Golden Cliffs above the Iss to summon them with weird cry to the victims floating down to their maws upon the cold, broad bosom of ancient Iss.

The navies of Helium and the First Born had cleared the fortresses and the temples of the therns when they had refused to surrender and accept the new order of things that had swept their false religion from long-suffering Mars.

In a few isolated countries they still retained their age-old power; but Matai Shang, their hekkador, Father of Therns, had been driven from his temple. Strenuous had been our endeavors to capture him; but with a few of the faithful he had escaped, and was in hiding-where we knew not.

As I came cautiously to the edge of the low cliff overlooking the Lost Sea of Korus I saw Thurid pushing out upon the bosom of the shimmering water in a small skiff-one of those strangely wrought craft of unthinkable age which the Holy Therns, with their organization of priests and lesser therns, were wont to distribute along the banks of the Iss, that the long journey of their victims might be facilitated.

Drawn up on the beach below me were a score of similar boats, each with its long pole, at one end of which was a pike, at the other a paddle. Thurid was hugging the shore, and as he passed out of sight round a near-by promontory I shoved one of the boats into the water and, calling Woola into it, pushed out from shore.

The pursuit of Thurid carried me along the edge of the sea toward the mouth of the Iss. The farther moon lay close to the horizon, casting a dense shadow beneath the cliffs that fringed the water. Thuria, the nearer moon, had set, nor would it rise again for near four hours, so that I was ensured concealing darkness for that length of time at least.

On and on went the black warrior. Now he was opposite the mouth of the Iss. Without an instant's hesitation he turned up the grim river, paddling hard against the strong current.

After him came Woola and I, closer now, for the man was too intent upon forcing his craft up the river to have any eyes for what might be transpiring behind him. He hugged the shore where the current was less strong.

Presently he came to the dark cavernous portal in the face of the Golden Cliffs, through which the river poured. On into the Stygian darkness beyond he urged his craft.

It seemed hopeless to attempt to follow him here where I could not see my hand before my face, and I was almost on the point of giving up the pursuit and drifting back to the mouth of the river, there to await his return, when a sudden bend showed a faint luminosity ahead.

My quarry was plainly visible again, and in the increasing light from the phosphorescent rock that lay embedded in great patches in the roughly arched roof of the cavern I had no difficulty in following him.

It was my first trip upon the bosom of Iss, and the things I saw there will live forever in my memory.

Terrible as they were, they could not have commenced to approximate the horrible conditions which must have obtained before Tars Tarkas, the great green warrior, Xodar, the black dator, and I brought the light of truth to the outer world and stopped the mad rush of millions upon the voluntary pilgrimage to what they believed would end in a beautiful valley of peace and happiness and love.

Even now the low islands which dotted the broad stream were choked with the skeletons and half devoured carcasses of those who, through fear or a sudden awakening to the truth, had halted almost at the completion of their journey.

In the awful stench of these frightful charnel isles haggard maniacs screamed and gibbered and fought among the torn remnants of their grisly feasts; while on those which contained but clean-picked bones they battled with one another, the weaker furnishing sustenance for the stronger; or with clawlike hands clutched at the bloated bodies that drifted down with the current.

Thurid paid not the slightest attention to the screaming things that either menaced or pleaded with him as the mood directed them-evidently he was familiar with the horrid sights that surrounded him. He continued up the river for perhaps a mile; and then, crossing over to the left bank, drew his craft up on a low ledge that lay almost on a level with the water.

I dared not follow across the stream, for he most surely would have seen me. Instead I stopped close to the opposite wall beneath an overhanging mass of rock that cast a dense shadow beneath it. Here I could watch Thurid without danger of discovery.

The black was standing upon the ledge beside his boat, looking up the river, as though he were awaiting one whom he expected from that direction.

As I lay there beneath the dark rocks I noticed that a strong current seemed to flow directly toward the center of the river, so that it was difficult to hold my craft in its position. I edged farther into the shadow that I might find a hold upon the bank; but, though I proceeded several yards, I touched nothing; and then, finding that I would soon reach a point from where I could no longer see the black man, I was compelled to remain where I was, holding my position as best I could by paddling strongly against the current which flowed from beneath the rocky mass behind me.

I could not imagine what might cause this strong lateral flow, for the main channel of the river was plainly visible to me from where I sat, and I could see the rippling junction of it and the mysterious current which had aroused my curiosity.

While I was still speculating upon the phenomenon, my attention was suddenly riveted upon Thurid, who had raised both palms forward above his head in the universal salute of Martians, and a moment later his "Kaor!" the Barsoomian word of greeting, came in low but distinct tones.

I turned my eyes up the river in the direction that his were bent, and presently there came within my limited range of vision a long boat, in which were six men. Five were at the paddles, while the sixth sat in the seat of honor.

The white skins, the flowing yellow wigs which covered their bald pates, and the gorgeous diadems set in circlets of gold about their heads marked them as Holy Therns.

As they drew up beside the ledge upon which Thurid awaited them, he in the bow of the boat arose to step ashore, and then I saw that it was none other than Matai Shang, Father of Therns.