You and I can never lift this out of here."

His glance darted about. There was a small door in the metal beam. The groove in which the sh.e.l.ls were placed led to it; it was a port for launching the projectiles. He moved it, opened it. A dash of spray struck him in the face. He glanced inquiringly at his companion.

"Dare we do it?" he asked. "Slide one of them out?"

Each man looked long into the eyes of the other. Was this, then, the end of their terrible night? One sh.e.l.l to be dropped--then a bursting volcano to blast them to eternity....

"The boys in the planes risked it," said Thurston quietly. "They got theirs." He stopped for a broken fragment of steel. "Try one with a fan on; it hasn't a detonator."

The men pried at the slim thing. It slid slowly toward the open port.

One heave and it balanced on the edge, then vanished abruptly. The spray was cold on their faces. They breathed heavily with the realization that they still lived.

There were days of horror that followed, horror tempered by a numbing paralysis of all emotions. There were bodies by thousands to be heaped in the pit where San Diego had stood, to be buried beneath countless tons of debris and dirt. Trains brought an army of helpers; airplanes came with doctors and nurses and the beginning of a mountain of supplies. The need was there; it must be met. Yet the whole world was waiting while it helped, waiting for the next blow to fall.

Telegraph service was improvised, and radio receivers rushed in. The news of the world was theirs once more. And it told of a terrified, waiting world. There would be no temporizing now on the part of the invaders. They had seen the airplanes swarming from the ground--they would know an airdrome next time from the air. Thurston had noted the windows in the great sh.e.l.l, windows of dull-colored gla.s.s which would protect the darkness of the interior, essential to life for the horrible occupant, but through which it could see. It could watch all directions at once.

The great sh.e.l.l had vanished from the sh.o.r.e. Pounding waves and the shifting sands of high tide had obliterated all trace. More than once had Thurston uttered devout thanks for the chance sh.e.l.l from an anti-aircraft gun that had entered the funnel beneath the machine, had bent and twisted the arrangement of mirrors that he and MacGregor had seen, and, exploding, had cracked and broken the domed roof of the bulb. They had learned little, but MacGregor was up north within reach of Los Angeles laboratories. And he had with him the slim cylinder of death. He was studying, thinking.

Telephone service had been established for official business. The whole nation-wide system, for that matter, was under military control. The Secretary of War had flown back to Washington. The whole world was on a war basis. War! And none knew where they should defend themselves, nor how.

An orderly rushed Thurston to the telephone. "You are wanted at once; Los Angeles calling."

The voice of MacGregor was cool and unhurried as Thurston listened.

"Grab a plane, old man," he was saying, "and come up here on the jump."

The phrase brought a grim smile to Thurston's tired lips. "h.e.l.l's popping!" the Secretary of War had added on that evening those long ages before. Did MacGregor have something? Was a different kind of h.e.l.l preparing to pop? The thoughts flashed through the listener's mind.

"I need a good deputy," MacGregor said. "You may be the whole works--may have to carry on--but I'll tell you it all later. Meet me at the Biltmore."

"In less than two hours," Thurston a.s.sured him.

A plane was at his disposal. Riley's legs were functioning again, after a fashion. They kept the appointment with minutes to spare.

"Come on," said MacGregor, "I'll talk to you in the car." The automobile whirled them out of the city to race off upon a winding highway that climbed into far hills. There was twenty miles of this; MacGregor had time for his talk.

"They've struck," he told the two men. "They were over Germany yesterday. The news was kept quiet: I got the last report a half-hour ago. They pretty well wiped out Berlin. No air-force there. France and England sent a swarm of planes, from the reports. Poor devils! No need to tell you what they got. We've seen it first hand. They headed west over the Atlantic, the four machines. Gave England a burst or two from high up, paused over New York, then went on. But they're here somewhere, we think. Now listen:

"How long was it from the time when you saw the first monster until we heard from them again?"

Thurston forced his mind back to those days that seemed so far in the past. He tried to remember.

"Four days," broke in Riley. "It was the fourth day after we found the devil feeding."

"Feeding!" interrupted the scientist. "That's the point I am making.

Four days. Remember that!

"And we knew they were down in the Argentine five days ago--that's another item kept from an hysterical public. They slaughtered some thousands of cattle; there were scores of them found where the devils--I'll borrow Riley's word--where the devils had fed. Nothing left but hide and bones.

"And--mark this--that was four days before they appeared over Berlin.

"Why? Don't ask me. Do they have to lie quiet for that period miles up there in s.p.a.ce? G.o.d knows. Perhaps! These things seem outside the knowledge of a deity. But enough of that! Remember: four days! Let us a.s.sume that there is this four days waiting period. It will help us to time them. I'll come back to that later.

"Here is what I have been doing. We know that light is a means of attack. I believe that the detonators we saw on those bombs merely opened a seal in the sh.e.l.l and forced in a flash of some sort. I believe that radiant energy is what fires the blast.

"What is it that explodes? n.o.body knows. We have opened the sh.e.l.l, working in the absolute blackness of a room a hundred feet underground.

We found in it a powder--two powders, to be exact.

"They are mixed. One is finely divided, the other rather granular. Their specific gravity is enormous, beyond anything known to physical science unless it would be the hypothetical neutron ma.s.ses we think are in certain stars. But this is not matter as we know matter; it is something new.

"Our theory is this: the hydrogen atom has been split, resolved into components, not of electrons and the proton centers, but held at some halfway point of decomposition. Matter composed only of neutrons would be heavy beyond belief. This fits the theory in that respect. But the point is this: When these solids are formed--they are dense--they represent in a cubic centimeter possibly a cubic mile of hydrogen gas under normal pressure. That's a guess, but it will give you the idea.

"Not compressed, you understand, but all the elements present in other than elemental form for the reconstruction of the atom ... for a million billions of atoms.

"Then the light strikes it. These dense solids become instantly a gas--miles of it held in that small s.p.a.ce.

"There you have it: the gas, the explosion, the entire absence of heat--which is to say, its terrific cold--when it expands."

Slim Riley was looking bewildered but game. "Sure, I saw it snow," he affirmed, "so I guess the rest must be O.K. But what are we going to do about it? You say light kills 'em, and fires their bombs. But how can we let light into those big steel sh.e.l.ls, or the little ones either?"

"Not through those thick walls," said MacGregor. "Not light. One of our anti-aircraft sh.e.l.ls made a direct hit. That might not happen again in a million shots. But there are other forms of radiant energy that do penetrate steel...."

The car had stopped beside a grove of eucalyptus. A barren, sun-baked hillside stretched beyond. MacGregor motioned them to alight.

Riley was afire with optimism. "And do you believe it?" he asked eagerly. "Do you believe that we've got 'em licked?"

Thurston, too, looked into MacGregor's face: Riley was not the only one who needed encouragement. But the gray eyes were suddenly tired and hopeless.

"You ask what I believe," said the scientist slowly. "I believe we are witnessing the end of the world, our world of humans, their struggles, their grave hopes and happiness and aspirations...."

He was not looking at them. His gaze was far off in s.p.a.ce.

"Men will struggle and fight with their puny weapons, but these monsters will win, and they will have their way with us. Then more of them will come. The world, I believe, is doomed...."

He straightened his shoulders. "But we can die fighting," he added, and pointed over the hill.

"Over there," he said, "in the valley beyond, is a charge of their explosive and a little apparatus of mine. I intend to fire the charge from a distance of three hundred yards. I expect to be safe, perfectly safe. But accidents happen.