“The castle!” Ashe’s cry pulled their attention back to land.
There was movement along those walls. Then came a flash, a splash in the water close enough to the lead ship to wet her deck with spray.
“They’re fighting!” Karara shouldered against Ross for a better look.
The ships were altering course, swinging away from land, out to sea.
“Moving too fast for sails alone, and I don’t see any oars.” Ross was puzzled. “How do you suppose. …”
The bombardment from the castle continued but did not score any hits. Already the ships were out of range, the lead vessel off the screen of the peep as well. Then there was just the castle in the sunset. Ashe straightened up.
“Rocks!” he repeated wonderingly. “They were throwing rocks!”
“But those ships, they must have had engines. They weren’t just depending on sails when they retreated.” Ross added his own cause for bewilderment.
Karara looked from one to the other. “There is something here you do not understand. What is wrong?”
“Catapults, yes,” Ashe said with a nod. “Those would fit periods corresponding from the Roman Empire into the Middle Ages. But you’re right, Ross, those ships had power of some kind to take them offshore that quickly.”
“A technically advanced race coming up against a more backward one?” hazarded the younger man.
“Could be. Let’s go forward some.” The incoming tide was washing well up on the reef. Ashe had to don his mask as he plunged head and shoulders under water to make the necessary adjustment.
Once more he pressed the button. And Ross’s gasp was echoed by one from the girl. The cliff again, but there was no castle dominating it, only a ruin, hardly more than rubble. Now, above the sites of the saucer depressions great pylons of silvery metal, warmed into fire brilliance by the sunset, raked into the sky like gaunt, skeleton fingers. There were no ships, no signs of any life. Even the vegetation which had showed on shore had vanished. There was an atmosphere of stark abandonment and death which struck the Terrans forcibly.
Those pylons, Ross studied them. Something familiar in their construction teased his memory. That refuel planet where the derelict ship had set down twice, on the voyage out and on their return. That had been a world of metal structures, and he believed he could trace a kinship between his memory of those and these pylons. Surely they had no connection with the earlier castle on the cliff.
Once more Ashe ducked to reset the probe. And in the fast-fading light they watched a third and last picture. But now they might have been looking at the island of the present, save that it bore no vegetation and there was a rawness about it, a sharpness of rock outline now vanished.
Those pylons, were they the key to the change which had come upon this world? What were they? Who had set them there? For the last Ross thought he had an answer. They were certainly the product of the galactic empire. And the castle … the ships … natives … settlers? Two widely different eras, and the mystery still, lay between them. Would they ever be able to bring the key to it out of time?
They swam for the shore where Ui had a fire blazing and their supper prepared.
“How many years lying between those probes?” Ross pulled broiled fish apart with his fingers.
“That first was ten thousand years ago, the second,” Ashe paused, “only two hundred years later.”
“But”—Ross stared at his superior—“that means—”
“That there was a war or some drastic form of invasion, yes.”
“You mean that the star people arrived and just took over this whole planet?” Karara asked. “But why? And those pylons, what were they for? How much later was that last picture?”
“Five hundred years.”
“The pylons were gone, too, then,” Ross commented. “But why—?” he echoed Karara’s question.
Ashe had taken up his notebook, but he did not open it. “I think”—there was a sharp, grim note in his voice—“we had better find out.”
“Put up a gate?”
Ashe broke all the previous rules of their service with his answer:
“Yes, a gate.”
IV
Storm Menace
“We have to know.” Ashe leaned back against the crate they had just emptied. “Something was done here—in two hundred years—and then, an empty world.”
“Pandora’s box.” Ross drew a hand across his forehead, smearing sweat and fine sand into a brand.
Ashe nodded. “Maybe we run that risk, loosing all the devils of the aliens. But what if the Reds open the box first on one of their settlement worlds?”
There it was again, the old thorn which prodded them into risks and recklessness. Danger ahead on both paths. Don’t risk trying to learn galactic secrets, but don’t risk your enemy’s learning them either. You held a white-hot iron in both hands in this business. And Ashe was right, they had stumbled on something here which hinted that a whole world had been altered to suit some plan. Suppose the secret of that alteration was discovered by their enemies?
“Were the ship and castle people natives?” Ross wondered aloud.
“Just at a guess they were, or at least settlers who had been established here so long they had developed a local form of civilization which was about on the level of a feudal society.”
“You mean because of the castle and the rock bombardment. But what about the ships?”
“Two separate phases of a society at war, perhaps a more progressive against a less technically advanced. American warships paying a visit to the Shogun’s Japan, for example.”
Ross grinned. “Those warships didn’t seem to fancy their welcome. They steered out to sea fast enough when the rocks began to fall.”
“Yes, but the ships could exist in the castle pattern; the pylons could not!”
“Which period are you aiming for first—the castle or the pylons?”
“Castle first, I think. Then if we can’t pick up any hints, we’ll take some jumps forward until we do connect. Only we’ll be under severe handicaps. If we could only plant an analyzer somewhere in the
