"It's the only chance."

I said nothing more. I knew that I could stand no such march on my frozen feet, but I resolved to say nothing about it. I would help them as far as I could, and then walk out of camp some night. Men have done just that.

Mildred brought out sacks of the little cakes, and of a red powder that seemed to be the dried and ground flesh of a crimson mushroom. We made a pack for each of us, as heavy as we could carry.

Just before we were ready to start Ray took off my footgear and treated my feet from his medicine kit. I had feared gangrene, but he a.s.sured me that there was no danger if they were well cared for.

Walking was still exquisitely painful to me as we slipped out through the arched door and into the fungoid forest beyond the three blue cylinders.

As rapidly and silently as possible we hastened through the brilliant fungous forest, across the river of opalescent liquid, to the foot of the fall of fire. A weird and splendid sight was that sheer arc of shimmering white flame, roaring into a pool of opal light, and surrounded with a mist of moon-flame.

We reached the foot of the metal ladder spiked to the rocks beside the fall and started up immediately. The going was not easy. The packs of food, heavy enough when we were on level ground, were difficult indeed to lift when one was scrambling up over rungs four feet apart.

Ray climbed ahead, with a piece of rope fastened from his waist to Mildred's, so that he could help her if she slipped. I was below the girl. We were halfway up the rock when suddenly a glare of red light shone upon me, casting my shadow sharply on the cliff. I looked up and saw the broad, intensely red beam of a heat-ray like that we had seen the giant crab use.

The ray came, evidently, from the sh.o.r.e of the great lake with its submerged city of blue cylinders. It fell upon the face of the cliff just above us. Quickly the ladder was heated to cherry red. The face of the rock grew incandescent, cracked. Hot sparks rained down upon us.

Slowly the ray moved down, toward us.

"Guess we'd better call it off," said Ray. "They have the advantage right now. Better get to climbing down, Jim. This ladder is going to be burning my hands pretty soon."

I climbed down. Mildred and Ray scrambled down behind me.

The ray followed us, keeping the metal at a cherry red just above Ray's hands.

I looked down and saw a dozen of the giant crabs lumbering up out of the fungoid jungle from the direction of the great lake. Hideous things they were, with staring, stalked eyes, shining green antennae, polished red sh.e.l.ls, claw-armed limbs. Like the one that had pa.s.sed us in the upper cavern, they wore glistening white metal accoutrements.

We clambered down, with the red ray following.

I dropped to the ground among them, wet with the sweat of horror. I reeled in nausea from the intolerable odor of the crab-things; it was indescribable, overpowering.

Curious rasping stridulations came from them, sounds which seemed to serve as means of communication, and which Mildred evidently understood.

"They say that you will not be harmed, but that you must not go out,"

she called down.

I was seized by the pincher-like claws, held writhing in an unbreakable grasp, while the glittering eyes twisted about, looked at me, and the shining green tentacles wavered questioningly over me. My stomach revolted at the horrible odor.

The crabs tore off my pack, even my clothing. Ray was similarly treated as soon as he reached the ground. Though they took Mildred's pack, they treated her with a curious respect.

In a few minutes they released us. They had taken the packs, the rifle and ammunition, our medicine kit and the few instruments we had brought with us down the shaft, even our clothing. They turned us loose stark naked. Ray's face and neck went beet-red when he saw Mildred standing by him.

The rasping sound came from one of them again.

"It says you may stay with me," Mildred said. "They will not harm you unless you try again to get away. If you do, you die--as father did.

They will keep what they took from you."

Several of the creatures went sc.r.a.ping off, carrying the articles they had taken from us either in their claws or in the metal cases they wore. Several waited, staring at us with the stalked compound eyes, and waving the green antennae as if they were organs of some special sense.

Two of the creatures waited at the foot of the metal ladder, holding the long slender white tubes of the heat-ray in their claws.

"They say we can go now," Mildred said.

She led the way toward the edge of the brilliant jungle. She seemed to be without false modesty, for I saw her glancing with evident admiration at Ray's lithe and powerful white-skinned figure. We followed her into the giant mushrooms, glad to escape the overpowering stench of the crabs.

In a few minutes we arrived again at the strange building of the three blue cylinders. Mildred, noticing our discomfort, produced for each of us a piece of white silken fabric with which we draped ourselves.

She had noticed my difficulty in walking on bare feet. She had me bathe them, then dressed them with a soothing yellow oil, and bandaged them skilfully.

"Anyhow," she said later, "it is good to have both of you here with me. I am sorry indeed for you that you may never see your country again. But it is good fortune for me. I was so lonely."

"These d.a.m.ned crabs don't know me!" Ray Summers muttered. "They think I'll play around like a pet kitten, for the rest of my life! They'll get their eyes opened. We'll spend the winter on Palm Beach yet!"

"It seems to me that we're rather outnumbered." I said. "And it's rather more pleasant in here than outside."

"I'm going to get that rifle," Ray declared, "and give these big crabs a little respect for humanity!"

"Let's rest up a while first, anyhow," I urged.

Presently Mildred noticed how tired we were. She went into the third of the connected cylinders of blue crystal, was busy a few minutes and called us to the couches she had prepared there.

"You may sleep," she told us. "The Things never come here. And they said they would not harm you, if you did not try to go out."

We lay down on the silken beds. In a few minutes I was sleep. I awoke to feel a curious unease, a sense of impending catastrophe. Ray was bending over me, his face drawn with anxiety.

"Something's happened!" he whispered. "She's gone!"

I sat up, staring into the liquid blue vastness of the tall cylinder above us.

"Listen! What's that?"

A deep bell-note sounded out, brazen, clanging. Sonorous, throbbing, mighty, it rang through the cylindered rooms. Slowly it died; faded to silence with a last ringing pulse. Tense minutes of silence pa.s.sed.

Again it boomed out, throbbed, and died. After more long minutes there was yet a third.

"Outside, somewhere!"

Ray started; ran to the arched door. We looked out upon the dense forest of gold and crimson mushrooms that grew below the black cavern roof. Before us, across a few hundred yards of bare rocky beach, was the edge of the crystal lake with the city of blue cylinders upon its floor.

"G.o.d! What's that?" Ray gripped my arm crushingly.

A thin wailing scream came across the beach from the black lake. A piteous sound it was, plaintive, pleading. Higher and higher it rose, until it was a piercing silver note. Clear and sweet it was, but inexpressibly lonely, sorrowful, mournful. It sank slowly, died away.