At five hundred miles he unshielded the ports, which of necessity had to be kept covered in clear space. There was a sky which was vividly bright with stars. There was a vast blackness off to starboard which was the night side of the planet.
He went down. At four hundred miles the outside-pressure indicator wavered away from its pin. He used it like a pilot-tube recording, doing sums in his head to figure the static pressure that should exist at this height, to compare with the dynamic pressure produced by his velocity through the near hard vacuum. The pressure should have been substantially zero. He swung the ship end-for-end and killed velocity to bring the pressure indication down. The ship descended. Two hundred miles. He saw the thin bright line of sunshine at the limb of the planet. Down to one hundred. He cut the rockets and let the ship fall silently, swinging its nose up.
At ten miles he listened for man-made radiation. There was nothing in the electromagnetic spectrum but the crackling of static in an electric storm which might be a thousand miles away. At five miles height the nearest-object indicator, near the bottom of its scale, wavered in a fashion to prove that he was still moving laterally across mountainous country. He swung the ship and killed that velocity too.
At two miles he used the rockets for deceleration. The pencil-thin flame reached down for an incredible distance. By naked-eye observation out a port, he tilted the fiercely roaring, swiftly falling ship until hillsides and forests underneath him ceased to move. By that time he was very low indeed.
He reached ground on a mountainside which was lighted by the blue-white flame of the rocket blast. He chose an area in which the treetops were almost flat, indicating something like a plateau underneath. Murgatroyd was practically frantic by this time because of his capture and the pinching of his tail, but Calhoun could not spare time to release him. He let the ship down gently, gently, trying to descend in an absolutely vertical line.
If he didn't do it perfectly, he came very close. The ship settled into what was practically a burned-away tunnel among monstrous trees. The slender, high-velocity flame did not splash when it reached ground. It penetrated. It burned a hole for itself through humus and clay and bedrock. When the ship touched and settled, there was boiling molten stone some sixty feet underground; but there was only a small scratching sound as it came to rest. A flame-amputated tree limb rubbed tentatively against the hull.
Calhoun turned off the rockets. The ship swayed slightly and there were crunching noises. Then it was still on its landing fins.
"Now," said Calhoun, "I can take care of you, Murgatroyd."
He flicked on the switches of the exterior microphones, which were much more sensitive than human ears. The radiation detectors were still in action. They reported only the cracklings of the distant storm.
But the microphones brought in the moaning of wind over nearby mountaintops, and the almost deafening susurrus of rustling leaves. Underneath these noises there was a bedlam of other natural sounds. There were chirpings and hootings and squeaks, and the gruntings made by native animal life. These sounds had a singularly peaceful quality. When Calhoun toned them down to be no more than background noise, they suggested the sort of concert of night creatures which to men has always seemed an indication of purest tranquility.
Presently Calhoun looked at the pictures the photorecorder had taken while the telescope's field swept over the city. It was the colony-city reported to have been begun two years before to receive colonists from Dettra Two. It was the city of the landing grid which had tried to destroy the Med Ship as a dog kills a rat, by shaking it to fragments, some forty thousand miles in space. It was the city which had made Calhoun land with his vision plates blinded; which had drained his power reserves of some hundreds of millions of kilowatt-hours of energy. It was the city which had made his return to Med Headquarters impossible.
He inspected the telescopic pictures. They were very clear. They showed the city with astonishing detail. There was a lacy pattern of highways, with their medallions of multiple-dwelling units. There were the lavish park areas between the buildings of this planetary capital. There was the landing grid itself, a half-mile high structure of steel girders, a full mile in diameter.
But there were no vehicles on the highways. There were no specks on the overpasses to indicate people on foot. There were no 'copters on the building roofs, nor were there objects in mid-air to tell of air traffic.
The city was either deserted or it had never been occupied. But it was absolutely intact. The structures were perfect. There was no indication of past panic or disaster, and even the highways had not been overgrown by vegetation. But it was empty—or else it was dead.
But somebody in it had tried very ferociously and with singular effectiveness to try to destroy the Med Ship.
Calhoun raised his eyebrows and looked at Murgatroyd.
"Why is all this?" he asked. "Have you any ideas?"
"Chee!" shrilled Murgatroyd.
II
"The purpose of a contemplated human action is always the attainment of a desired subjective experience. But a subjective experience is desired both in terms of intensity and of duration. For an individual the temptingness of different degrees of intensity—of experience is readily computed. However, the temptingness of different durations is equally necessary for an estimate of the probability of a given person performing a given action. This modification depends on the individual's time sense; its acuity and its accuracy. Measurements of time sense . . ."
Probability and Human Conduct—Fitzgerald
Eventually Calhoun left the ship and found a cultivated field and a dead man and other things. But while in the Med Ship he found only bewilderment. The first morning he carefully monitored the entire communications spectrum. There were no man-made signals in the air of Maris III. That was proof the world was uninhabited. But the ship's external microphones picked up a rocket roar in mid-morning. Calhoun looked, and saw the faint white trail of the rocket against the blue of the sky. The fact that he saw it was proof that it was in atmosphere. And that was evidence that the rocket was taking photographs for signs of the crater the Med Ship should have made in a crash landing.
The fact of search was proof that the planet was inhabited, but the silence of the radio spectrum said that it wasn't. The absence of traffic in the city said that it was dead or empty, but there were people there because they'd answered Calhoun's hail, and tried to kill him when he identified himself. But nobody would want to destroy a Med Ship except to prevent a health inspection unless there was a situation aground that the Med Service ought to know about. But there should not be such a situation.
There was no logical explanation for such a series of contradictions. Civilized men acted either this way or that. There could only be civilized men here, yet they acted neither this way nor that. Therefore—and the confusion began all over again.
Calhoun dictated an account of events into the emergency responder in the ship. If a search call came from space, the responder would broadcast this data and Calhoun's intended action. He carefully shut off all other operating circuits so the ship couldn't be found by their radiation. He equipped himself for travel, and he and Murgatroyd left the ship. Obviously, he headed toward the city where whatever was wrong was centered.