Both were a trifle surprised when, on their return after the usual interval, discussion went on as though nothing had happened. Kruger wished he dared ask how the Teachers had escaped, but somehow failed to bring himself to the point of actually raising the question.
By this time he had told a good deal about his people. Dar had done the same. Kruger’s facility with the language had grown far more rapidly than in any similar period of his companionship with Dar alone.
Dar, by this time, had realized his original error about Kruger, though his ideas of astronomy were distinctly sketchy. The boy, however, was by no means convinced that Dar and the villagers were natives of the planet; the Teachers had always shied away from direct answers on that subject and there was no direct evidence which tended to disprove the original notion that they were maroons like himself — none, at least, that Kruger recognized as such.
Their stay in the village was not entirely composed of exploration and conversation. Several times life became fairly exciting, in fact. On one occasion Kruger fell into a concealed pit which had rather obviously been made to trap animals; only the fact that it seemed to have been made for rather large game enabled him to miss the sharpened stake in the bottom. Again, while leaving a building at one edge of the city well up the side of one of the volcanoes, Kruger and Dar were nearly engulfed by a slide of volcanic ash which had apparently been loosened by recent rain. They had ducked back into the building barely in time, and afterward had to make their way painfully — for Kruger, that is — through the structure to find an exit on the other side, the uphill doors having been completely blocked.
Several times Dar renewed his request for the return of the books; his time was running out, in more senses than one. The Teachers still professed interest in the volumes, however, and failed to give any definite time when the interest might be expected to wane.
Several times when he and Dar were alone Kruger suggested, more or less forcefully, that they simply fail to return to the village some day, get to the Ice Ramparts, and return with enough assistance to compel the return of Dar’s property; but the pilot refused to leave. It took a fairly complex combination of circumstances to change his mind.
They had covered the greater part of the city which lay toward the village but had done virtually nothing with the other side. Actually there was little reason to suppose that it would provide anything they had not seen already, and even Kruger was getting a little weary of rambling through deserted buildings, when Dar noticed that one street seemed to lead off from the farther side of the city around the second volcano, which they had never reached. This street was not noticeable from sea level; Dar saw it from the edge of the city well up the other hill — quite close, in fact, to the place where they had nearly been buried. The two decided to investigate immediately.
It took some time to descend one volcano, cross the level portion of the city, and climb the other to the point which Dar’s memory indicated as being the start of the street in question; when they reached it, enough time had passed to suggest that they might possibly be late for their next conversation with the Teachers. They had always been careful not to overstay their leave, feeling quite logically that their freedom might suffer should they do so, but this time they decided to take the chance.
The street went up the hill rather steeply, angling at first toward the seaward side of the cone. From below they had not been able to tell whether it formed a switchback leading to the top of the volcano or a spiral going around it; they learned fairly soon that it was the latter.
They rather hoped to get to the top so that they could get a better idea of the local geography than their walks had given them. Dar could see no sense in building a street that led to a mountain top, but was willing to suspend judgment until the evidence was in.
“In any case,” the pilot pointed out, “if you really want to get up there, there’s no need to follow a road. We’ve both climbed hills before.”
“Yes, but I don’t know about climbing this hill. Remember what happened over on the other side of town. It would be rather bad if another of those landslides started and we had no building to duck into.”
“I don’t think we need worry. The ground on this cone looks a lot firmer than that on the other, and I haven’t seen any marks suggesting recent landslides.”
“I didn’t see any on the other side, either — and probably no one has been climbing this. Our disturbance might be all it was waiting for.”
They might have spared themselves the discussion; they never reached the top. The road ceased to climb at about the time the last of the city except the submerged portion was lost to view, and without even discussing the question the two continued to follow the paved way. The view was already extensive; when they looked back the bottom of the harbor revealed the extent to which it must once have been dry land, as the street pattern of the city showed through the clear water. Ahead, the nearly straight coastline vanished in distance many miles away.
Inland, the jungle extended as far as the eye could reach. Even from this height — which was not, after all, very great — they could not begin to see across the distance separating them from the lava field where they had met. There seemed no reason, so far, for building the road at all; it seemed to lead nowhere. With mounting curiosity they hastened along it.
A quarter of a mile beyond the point where even the harbor had vanished from view they came upon the crater. There was virtually no warning; one moment the hillside sloped up and down away from the road at the usual angle; the next, the region downhill had vanished and the road was running perilously along the edge of a three-hundred-foot cliff. A heavy metal guard rail was there and the two approached this and leaned over.
The crater, if that was what it had once been, was not in the top of the hill, but well to one side; the road had led them to the highest point of its rim and the cone went up several hundred more feet behind them as they stood looking into it. It was not a very orthodox crater; the inner walls were sheer cliffs, which at first made Kruger feel decidedly insecure. Then he saw that the inner wall of the pit was not made of the same material as the hillside in general, and very slowly it dawned on him that the whole thing was artificial.
The walls were of concrete, or some equivalent composition. They had been shaped by tools. The bottom was not the tapering cone of the usual small crater but neither was it completely level. There was a small lake, and vegetation floored most of the rest of the area. Around the edge the concrete wall material seemed to extend horizontally for a short distance, and on this there was no vegetation. Both watchers were able to see the mouths of caves or tunnels opening from the wall onto this ramp, and with one mind they started looking for a Way down.
There was nothing remotely resembling a ladder anywhere on the inner wall,
Shortly after this they reached a point where the trees grew right up to the edge of the road, overhanging both it and the pit. This had prevented their learning the course of the road from above; as it turned out, it had also prevented their seeing a number of buildings which were spaced at fairly regular intervals down the slope. These appeared to be built in the same style as the ones in the city except that they were all single-storied. Dar and Kruger wondered whether to examine them in detail now or find where the road led and come back later if there was time. The second alternative won.
However, it did not take long to find where the road led. Another two hundred yards down the slope it opened out into a paved space which Kruger labeled “parking lot” in his mind without even thinking. Several minutes of thought and investigation revealed no better name for it, so the two explorers returned to the buildings. Once inside the first of these, all recollection of the fact that they were already late for their appointment with the Teachers vanished from Kruger’s mind.
His first supposition was that this must be the city power plant. An electric generator is going to look pretty much the same whoever builds it and whatever causes it to turn, and the objects in the first building were quite plainly electric generators. They were large, though Kruger lacked the knowledge to tell whether they were large enough to supply the whole city. Their great armatures were mounted on vertical axles, and apparently the source of mechanical energy was below ground level. With this in mind the two made a rapid search and were rewarded by finding the head of a ramp that led downward as expected.
The only difficulty was that the ramp was both narrow and low. Kruger would have to go down on his hands and knees, and the slope was steep. Even if he worked his way down backward return would be difficult if not
