of earth faults. Craig had seen a few of those areas where the foundations of the earth had crumpled. If the inconceivable pressures of the planet could crush miles of rock like he could crush a playing card in his hands, why could not the more tenuous fabric of space-time be crushed also?

The faces of the officers reflected doubt. Craig saw them steal uneasy glances at each other, saw them glance at the bulk of the battleship for reassurance. The ship was their world.

Out of the corner of his eyes Craig saw something coming across the sea. At the same time, in the forepeak, a lookout sang out.

"I'm afraid," Craig said, pointing, "that now there is no doubt that Mr. Michaelson is right. Look there."

Sailing down the wind was a gigantic bird-lizard. With great fanged beak out-stretched, it was flapping through the air on leathery wings. It was a creature out of the dawn of time.

It proved, by its mere existence, that Michaelson was right.

The Idaho, and all her crew, had passed through a space-time fault into an antediluvian world!

CHAPTER III

The Return of the Dove

There were dozens of the great bird-lizards flapping about the ship. Either they thought it was an enemy, to be attacked and destroyed, or they thought it was something to eat. In either event, it was to be attacked. They were attacking it. They would circle it, flap heavily to a point above, then launch themselves into a glide, fanged mouth open, screaming shrilly.

The anti-aircraft gunners knocked the beasts out of the air with ease.

On the bridge a group of tense officers watched the slaughter without being greatly interested in it. They knew that the guns of the Idaho were proof against any creature of earth, sky, or water, in this world. They were not afraid of the beasts of this strange time into which they had been thrust.

The scouting plane was still out, searching the waste of water for land.

The officers of the Idaho were all thinking the same thing. Captain Higgins put their thoughts into words.

"Mr. Michaelson," the captain said slowly. "I can't argue with you. I am forced to believe that somehow we have been forced back in time. However I am charged with the responsibility for this ship. Back where we came from, the Idaho is needed. I want to get her back where she belongs. How can we accomplish this?"

The scientist hesitated. He did not want to say what he had to say. He shook his head. "I question whether or not we can accomplish it," he said at last.

"But we have to return!" Higgins protested.

"I know," Michaelson said sympathetically. "The problem is how!"

"You mean there is no way to return?"

The scientist shrugged. "If there is, I do not know of it."

"But can't you make any suggestion? After all, this is your field. You're a scientist."

"This is my field but even I know little or nothing about it. Almost nothing is known about the true nature of the space-time continuum. Only recently have we even guessed that such things as space-time faults existed. We were hurled through this particular fault by accident, the result of an unfortunate combination of circumstances. Whether we can duplicate that accident, and whether it would return us to our own time—I just don't know. Nobody knows."

The officers of the Idaho received this information with no sign of pleasure. Craig felt sorry for them. After all, some of them had wives, all of them had friends back in the United States. Or was it forward in the United States, in the America that was to be? It was hard to remember that Columbus had not as yet sailed westward, would not sail westward for—how many hundreds of thousands of years?

All human history would have to unroll before there was an America. If the theory of continental drift was correct, there might not even be an American continent, it might still be joined to Europe. Babylon and Nineveh, Karnak and Thebes, Rome and London—there were no such cities in the world, would not be for—

The men on this ship were probably the only human beings alive on earth! Men had not yet become human, or maybe hadn't. The Neanderthal Man, the Cro-Magnons, maybe the Java Man, the Piltdown Man, had not yet appeared on the planet!

"As I understand it," an officer said, "we were sailing directly across a space-time fault when the explosion of the bombs sent us through the fault? Is that correct?"

"That is correct," Michaelson answered.

"Then why don't we locate this fault and set off some explosions of our own?" the officer suggested. "Is there any chance that we might return—home—that way?"

"I don't know," the scientist frankly answered. "Maybe it would work, maybe it won't. We can certainly try it, and if it fails, nothing is lost. Meanwhile I will go over my data and see if I can find some way of accomplishing what we desire."

Michaelson went below. The Idaho was brought around. Immediately a worried officer posed another problem.

"How are we going to find that fault?" he asked. "We can't see it. We can't feel it. How are we going to know when we have reached the right place?"

"We'll search the whole area," Higgins said. "We haven't moved far and locating the fault ought not to be too difficult. For that matter, we are probably still in it."

The officers moved quickly and efficiently to put his orders into execution. The plan was to put the ship in the same position she had occupied when the bombs struck, then use the small boats to plant explosive charges in the water around the battle wagon, charges which could be electrically exploded from the ship. Captain Higgins moved to where Craig was standing. He took off his cap and wiped perspiration from his forehead.

"What do you make of this?" he asked.

Craig shrugged. "I pass," he said.

"But—one minute we were part of a task force and Jap bombers were having a go at us. The next minute—" Higgins looked helpless. "Damn it, Craig," he exploded, "things like that can't happen!"

"They aren't supposed to happen," the big man grimly answered. "We just saw one of them happen."

"But—" Higgins protested, "surely we would have known about these space-time faults, if they existed. Other ships would have fallen into them."

"Maybe other ships have fallen into them," Craig suggested. "In the last war the Cyclops vanished without a trace. There have been other ships, dozens of them, that have disappeared. And, for that matter, how is the commander of your task force going to handle the disappearance of the Idaho?"

"I don't know," Higgins muttered.

"He is going to have to report the loss of the battleship. What will he say?"

"What can he say?"

"He'll search the area, for survivors and wreckage. When he finds neither the only conclusion he can reach will be that the Idaho was instantaneously sunk with the loss of all hands. Remember we were under attack at the time. Remember that intense blue light that flared around the horizon? To the men in the other ships that light may have looked like an explosion of the magazines of the Idaho. The admiral commanding your task force may report that a bomb seemingly passed down the smoke stack of the Idaho and the resulting explosion touched off the powder magazine."

Craig paused and in growing perplexity watched what Higgins was doing. The captain was vigorously kicking the steel wall of the bridge. He was pounding his right foot against it as if he was trying to kick it down. There was a look of pain on his face. Craig watched for a second, then grinned.

"Does it hurt?" he said.

"Yes!"

"Then it must be real," the big man suggested.

Higgins left off kicking the wall. Craig knew why he had been kicking it—to assure himself that the wall was really there. Higgins was a man in a nightmare but instead of pinching himself to