But it did not. The sound of Phil's footsteps ahead stopped, and when Sue and her father came up they saw why.

"A river!" Phil said.

They were standing on a narrow ledge that overhung an underground river. A fetid smell of age-old, lifeless water rose from it. Dimly, at least fifty feet across, they could see the other side, shrouded in vague shadows. The inky stream beneath did not seem to move at all, but remained smooth and hard and thick-looking.

They could not go around it. The ledge was only a few feet wide, and blocked at each side.

"Got to cross!" Phil said tersely.

Quade, sickly-faced, stared down. "There--there might be other things in that water!" he gasped. "Monsters!"

"Sure," agreed Phil contemptuously. "You'd better stay here." He turned to the others. "I'll see how deep it is," he said, and without the faintest hesitation dove flatly in.

Oily ripples washed back, and they saw his head poke through, sputtering. "Not deep," he said. "Chest-high. Come on."

He reached for Sue, helped her down, and did the same for her father.

Holding each by the hand, Sue's head barely above the water, he started across. They had not gone more than twenty feet when they heard Quade, left on the bank, give a hoa.r.s.e yell of fear and dive into the water. Their dread pursuer had caught up with them.

And it followed--on the water! Phil had hoped it would not be able to cross, but once more the thing's astounding adaptability dashed his hopes. Without hesitation, the whitish jelly sprawled out over the water, rolling after them with ghastly, snake-like ripples, its pallid body standing out gruesomely against the black, odorous tide.

Quade came up thrashing madly, some feet to the side of the other three. He was swimming--and swimming with such strength that he quickly left them behind. He would be across before they; and that meant there was a good chance that the earth-borer would go up again with only one pa.s.senger....

Phil fought against the water, pulling Sue and her father forward as best he could. From behind came the rippling sound of their shapeless pursuer. "Ten feet more--" Holmes began--then abruptly stopped.

There had been a swish, a ripple upstream. And as their heads turned they saw the water part and a black head, long, evil, glistening, pointing coldly down to where they were struggling towards the sh.o.r.e.

Phil Holmes felt his strength ooze out. He heard Professor Guinness gasp:

"A water-snake!"

Its head was reared above the surface, gliding down on them silently, leaving a wedge of long, sluggish ripples behind. When thirty feet away the glistening head dipped under, and a great half-circle of leg-thick body arched out. It was like an oily stream of curved cable; then it ended in a pointed tail--and the creature was entirely under water....

With desperate strength Phil hauled the girl to the bank and, standing in several feet of water, pushed her up. Then he whirled and yanked old Guinness past him up into the hands of his daughter. With them safe, and Sue reaching out her hand for him, he began to scramble up himself.

But he was too late. There was a swish in the water behind him, and toothless, hard-gummed jaws clamped tight over one leg and drew him back and under. And with the touch of the creature's mouth a stiff shock jolted him; his body went numb; his arms flopped limply down. He was paralyzed.

Sue Guinness cried out. Her father stared helplessly at the spot where his young partner had disappeared with so little commotion.

"It was an eel," he muttered dully. "Some kind of electric eel...."

Phil dimly realized the same thing. A moment later his face broke the surface, but he could not cry out; he could not move his little finger. Only his involuntary muscles kept working--his heart and his lungs. He found he could control his breathing a little.... And then he was wondering why he was remaining motionless on the surface.

Gradually he came to understand.

He had not felt it, but the eel had let go its hold on his leg, and had disappeared. But only for a moment. Suddenly, from somewhere near, its gleaming body writhed crazily, and a terrific twist of its tail hit Phil a glancing blow on the chest. He was swept under, and the water around him became a maelstrom. When next he bobbed to the tumultuous surface, he managed to get a much-needed breath of air--and in the swirling currents glimpsed the long, snake-like head of the eel go shooting by, with thin trickles of stuff that looked like white jelly clinging to it.

That explained what was happening. The eel had been challenged by the ameboid monster, and they were fighting for possession of him--the common prey.

The water became an inferno of whipping and lashing movements, of whitish fibers and spearing thrusts of a glistening black electric body. Unquestionably the eel was using its numbing electric shock on its foe. Time and time again Phil felt the amoeba grasp him, searingly, only to be wrenched free by the force of the currents the combat stirred up. Once he thudded into the bottom of the river, and his lungs seemed about to burst before he was again shot to the top and managed to get a breath. At last the water quieted somewhat, and Phil, at the surface, saw the eel bury its head in a now apathetic mound of flesh.

It tore a portion loose with savage jaws, a portion that still writhed after it was separated from the parent ma.s.s; and then the victor glided swiftly downstream, and disappeared under the surface....

Holmes floated helplessly on the inky water. He could see the amoeba plainly; it was still partly paralyzed, for it was very still. But then a faint tremor ran through it; a wave ran over its surface--and it moved slowly towards him once again.

Desperately Phil tried to retreat. The will was there, but the body would not work. Save for a feeble flutter of his hands and feet, he could not move. He could not even turn around to bid Sue and David Guinness good-by--with his eyes....

Then a fresh, loved voice sounded just behind him, and he felt something tighten around his waist.

"It's all right, dear!" the voice called. "Hang on; we'll get you out!"

Sue had come in after him! She had grasped the rope tied to his belt, and she and her father were pulling him back to the bank!

He wanted to tell her to go back--the amoeba was only feet away--but he could only manage a little croak. And then he was safe up on the ledge at the other side of the river.

A surge of strength filled his limbs, and he knew the shock was rapidly wearing off. But it was also wearing off of the monster in the water. Its speed increased; the ripplings of its amorphous body-substance became quicker, more excited. It came on steadily.

While it came, the girl and her father worked desperately over Phil, ma.s.saging his body and pulling him further up the bank. It had all but reached the bank when Holmes gasped:

"I think I can walk now. Where--where did Quade go to?"

Guinness gestured over to the right, up a dim winding pa.s.sage through the rocks.

"Then we must follow--fast!" Phil said, staggering to his feet. "He may get to the sphere first; he'll go up by himself even yet! I'm all right!"

Despite his words, he could not run, and could only command an awkward walk. Sue lifted one of his arms around her shoulder, and her father took the other, and without a backward glance they labored ahead. But Phil's strength quickly returned, and they raised the pace until they had broken once more into a stumbling run.

How far ahead James Quade was, they did not know, but obviously they could follow where he had gone. Once again the draft was strong on their backs. They felt sure they were on the last stretch, headed for the earth-borer. But, unless they could overtake Quade, he would be there first. They had no illusions about what that would mean....

CHAPTER V

_A Death More Hideous_

Quade was there first.

When they burst out of a narrow crevice, not far from the funnel-shaped opening they had originally entered, they saw him standing beside the open door of the sphere as if waiting. The searchlight inside was still on, and in its shaft of light they could see that he was smiling thinly, once more his old, confident self. It would only take him a second to jump in, slam the door and lock it. He could afford a last gesture....

The three stopped short. They saw something he did not.

"So!" he observed in his familiar, mocking voice. He paused, seeing that they did not come on. He had plenty of time.

He said something else, but the two men and the girl did not hear what it was. As if by a magnet their eyes were held by what was hanging above him, clinging to the lip of the hole the sphere had made in the ceiling.