Many of the vehicles were wrecked, as if their drivers had died at the controls and the untended machines had driven on senselessly until they crashed.
There were many quaintly human-like items in the dead civilization. The explorers found one little shop with identifiable cages in it, as if for small captive creatures, and collars of metal apparently intended for pets.
They found where groups of the vanished race had died as if in the midst of friendly conversation and—as their observation grew more acute—they saw that some of the heaps of garments were smaller than others, and that usually such small garments were beside larger ones, as if the murdered children had been with their parents.
Kit grew very pale. Rod glowered as they went on. The electrician with them scowled more and more deeply.
"Who killed all these folks?" he demanded pugnaciously. "It happened all at once an' it couldn't ha' been more'n a couple of years ago."
"I think," said Rod tonelessly, "it was the gang we ran away from. The gang that made a metal pyramid on Calypso. The same gang that built a metal pyramid not far from where I landed the ship—which we're going to make use of if we have luck."
The electrician spat. "An' you think they killed these people?"
"Because," Rod told him, "they made a space-ship. The pyramid on Calypso was supposed to tip them off when we did. The pyramid in the square back by the ship is bait. If there was a space-ship away from home when this world was killed and if it came back, the people in it would think some survivors of the catastrophe had left a record for them."
"They'd go inside to see. And they'd be killed. And the murderers would be notified to come and mop up just to make sure. See?"
The electrician spat again. "We'd better figure out something to slap them guys down," he said coldly. "They need it."
The three went on. And everywhere they moved through the city they saw new evidences of the high degree of civilization the dead race had achieved, more and more of the pathetic heaps of garments which had been members of that race. Kit, perhaps, saw those most clearly. The electrician saw also the enormous wealth left ownerless by the annihilation of its creators.
Not only was there a metropolis left, which humans could take over and use with little modification, but there were goods and even jewels—strangely-cut and very beautiful—and all the other portable possessions of a civilized world. He made no move to burden himself though. There was too much of riches in sight to make mere looting a temptation. But it was plain enough that he saw.
Rod saw the technical side of the murdered culture. He noted the lavish use of non-corrodible alloys. He saw plastics used where human-made plastics would not have been satisfactory. He took a small sliver of colorless transparent stuff and held a flame to it. It did not discolor or char.
"Looks like fluocarbon," he said absorbedly. "These people had gone places!"
Then they entered a great building which was plainly a power-station and a communication-center at once. Here Rod was in his element and the electrician was not far behind him. The central hall was huge and bright with sunlight and there were many machines upon the floor.
"Generator yonder," said Rod, nodding. "Looks like an electron-emitting isotope trick like ours. See the power-leads from it?"
The electrician observed, "Silver bus-bars. Looks like nylon insulation everywhere."
"Or fluocarbon plastic. Hm." Rod stared at a huge block of solid transparent stuff with metal sheets and rods deeply imbedded in it Power-leads ran to it but the metal sheets did not connect within the transparency. He stared while the others wandered about. Then Kit, a little distance away, uttered a cry.
"Rod! Come here! Oh—it's terrible!"
Rod went quickly. And Kit was standing with clenched hands before a double row of instruments. Between them the floor was quite covered with the bright garments of the dead race, showing that all the occupants of the building had been crowded here when death fell upon their city. And the rows of instruments showed why.
They were, in effect, television instruments. But it took time to realize it, because on each screen a distinct and motionless image remained. Each instrument still showed the picture that had been upon it at the instant the city died.
Some of the pictures were of individual members of the race in the act of speaking. Others—many others—were of scenes upon the ways, either of this city or another, showing the dead race as it had been. On two screens there was no hint of danger or of the coming of death.
But no less than six showed the death-agonies of those who were still not dead. The screens were horrible to look at. Three—and this was where the heaps of garments were thickest-showed the sky. Each showed a strange object against a background of clouds or stars. And the three were identical. Each was a monstrous metal pyramid.
Rod stared woodenly at the images. Then he examined the instruments which held them.
"Vision-screens," he announced unnecessarily. Then he added, "A good trick. They didn't project their television. They modified a plate of some sort that can change like—well—like the skin of a chameleon. Didn't have to worry about brightness. Like a photograph, only it must have moved. When the machine went off the last picture stayed until it went back on again."
He fumbled and peeled off a strip of flexible material which formed the screen. The image remained on it. It was, in effect, a photograph of the last object the dying eyes of these people had looked at. He hunted and found a stock of similar sheets—but blank—to be used as replacements.
"Television," he said, "only you could keep any scene you wanted to as a photograph. I think I've got a good hunch on what killed these people. The trouble is to prove it."
Kit caught her breath. She was grief-stricken at the pictures.
"Rod! They were so much like us! So much like us!"
"That flying pyramid was the destroyer," Rod pointed out "A pyramid's a good structural form—the most rigid you can make with straight girders. And there's no sense in streamlining a space-ship because there's no air-resistance in space. Besides, polished metal at such angles would reflect away radar-beams—solar heat too if they wanted to go close to a sun.
"My guess is that was a fighting-ship. It appeared in the sky overhead and these people's telescopes picked it up and they were watching it when they died."
The electrician said suddenly, "Hey! These sets must've blown out—"
"Whatever killed the people stopped the sets," agreed Rod coldly. "They wouldn't have switched them off just because they were dying. Whatever killed the people did something to the sets! If we open one up we may check on an idea I've got"
He saw the electrician reach in his overall pocket for tools. He went to the big block of plastic with the imbedded and covered metal plates. The thing bothered him. The plastic was plainly an insulator and as plainly the whole thing was designed to perform some electrostatic or electronic function. He felt that he ought to understand.
One of the plates wasn't solid metal but pierced with innumerable holes like a sieve. Rod frowned, a hunch telling him that this was important He tried to figure it out as an electrostatic device, guessing at capacity-effects between the enclosed plates. But this part would neutralize the capacity-effect between that and that and—
His mouth dropped open. It was a vacuum tube! Save that the parts were imbedded in plastic instead of held in emptiness, it was plainly a vacuum tube! The plastic must have acted electronically like a vacuum, allowing electron-flow. And they must have had the trick of cold emission of electrons from a metal surface! If that were so this device would handle incredible amounts of power!