we ditched. You could draw the area we’ve got as a thick-leaded line on a standard map.”
“I wonder why she chose that line,” I said. “It’s only inclined a few degrees to the line of latitude, but it’s considerably distant from the line of latitude which passes through the position she gave us as her own. She didn’t mind us landing a hundred miles away from her if it would allow us to scan this particular area. When Pete said the first area was too broad she shortened it both sides to hold the same central corridor. Can you sort out the line of pictures which shows the territory dead center of the area—the central five miles or so.”
“She didn’t know the exact whereabouts of what she wanted to find,” Karen pointed out. “She said it might take years of searching on the ground.” Even while she was complaining she was checking the serial numbers on a stack of photographs, sorting out the ones I wanted. I took another set and began doing likewise.
“True,” I admitted, “but she has some reference point somewhere—a place to start at and work out from. And it must be on this central line somewhere.”
It took us ten minutes to extract the sequence of shots we wanted, and a further ten to arrange them in the correct order.
“Incidentally,” I said, as I began spreading them around the floor in a long curve that spiraled around the table and then began to overlap itself, “as we’ll have passed directly overhead of all these points, I guess we’re on this line too.”
“Sure,” she said, extending a foot to tap the last photograph in the sequence and then moving it on a few inches to the non-existent frame which would have been next. “We’re about here. If you look west out of the ship’s cameras you should be able to see this ridge and the peak way back here.”
I tiptoed over the layout to the console and got an image of the outside on the display screen. I rotated the scanner. “There’s the ridge,” she said. “And the middle one of those three peaks is the one under my big toe.”
I looked down at the floor. “And the other two?”
“They’re on the parallel sets of pictures.”
It gave me a place to start. I began with the bit of empty floor that was our own position and began crawling along the spiral. My gaze went over the ridge—actually quite a gentle bump that was presumably a saddle strung between two mountains and separating two valleys—and then down a long shallow slope. The pictures were mottled with expanses of bare rock, rough grass and occasional areas of shrub. The farther down I went the greater grew the proportion of shrub, but there was very little heavily wooded land. At the bottom of the valley I crossed a stream and admired the lushest vegetation around, and then started climbing again—another long, shallow slope. There was nothing steep enough here to shield the bottom of the bowl from the wind, and I guessed that during the rainy season the storms could get pretty violent, which explained why the hold of the vegetation was a little precarious even though we were below the theoretical altitude of the tree line. I continued up the slope for a couple of frames, and was getting quite exhausted by the energy-sapping toil I could feel in my imagination.
Then I came to a much steeper upslope which reared to a narrow ridge and then plummeted again into a great elliptical bowl—an egg-shaped crater. Here, because of the high walls, there was protection from wind, and the inside of the crater had taken full advantage of that fact. Here, as nowhere else, there was a truly rich flora—and no doubt fauna too. The long axis of the crater was about ten miles in extent—or so I estimated, because it ran slantwise across the track, and the corner of it was chopped off—while the shorter axis was about seven.
“Look at that!” I said.
Karen looked at it, then referred back to the computer scan we had carried out on the pictures.
“The computer sorted that one out,” she said, as if that made it immediately uninteresting.
“It’s a funny-looking crater,” I said. “And it’s in a funny place. It’s not on top of a mountain—in fact it’s on the lower slopes. That long hill continues from the other ridge, up and up and up. And look at these lines at the northern wall. They must be fissures of some kind. These blurry wisps here and there might be vapor being blown out of them. And what are these, half-hidden by the trees?”
Karen got down on her hands and knees to look, but realized immediately how stupid we must have looked. She picked up the two frames containing most of the crater and put them back on the table where we could inspect them in a civilized manner. I checked the serial numbers and started rifling through the piles in search of the missing bit of the crater.
“They look to me,” said Karen, “rather like circular tents. But I wouldn’t swear to it. No one would. And over here might be the roof of a cabin. But we’re at the limits of resolution here and my eye is going crazy trying to make it out.”
“If we had an overlapping frame,” I said, “we could rig up a stereoscope and get a 3-D image.”
She shook her head. “We weren’t taking them that quickly,” she said. “These are just broken bits of what was actually a much larger image.”
“I think you’re right about the tents and the cabin,” I said, after long perusal and due consideration. “Someone’s in the crater. Mme. Levasseur didn’t mention that. If she knows about it, then the crater might be the point by which she set our course and selected the area for scanning. If she doesn’t know....”
“...it might be what she’s looking for.”
I pondered. “What kind of crater do you think that is?” I asked her.
“Volcanic,” she answered. “What else?”
“Elliptical in shape? On the lower slopes of a mountain?”
She shrugged. “What both of us know about vulcanology could be written on the back of a postage stamp,” she pointed out. Which was true enough.
She picked up another print from the floor and showed it to me. This was the one which included the actual mountain peak—the middle one of the three we could see through the scanner. There was no mistaking that one. It was volcanic all right, though seemingly long extinct. It had a big, deep cone which had solidified a long time ago. This crater too was filled with vegetation now, though it was by no means so rich as that in the egg-shaped crater, being several thousand feet higher up.
“So okay,” I said. “Way back when there was a double blast, with fire belching out of the side of the mountain as well as the cone. I guess volcanoes aren’t any tidier than the rest of nature.”
“It could hardly be the crater itself that Mme. Levasseur is looking for,” said Karen, picking up another thread. “It’s on the survey team’s maps, and it’s clearly visible from the slopes of the three peaks we can see. But if the people encamped in it are....”
She stopped then.
“Escaped criminals?” I suggested. “Leaders of the revolution? Escaped slaves?”
We exchanged a slightly significant glance. The last one was hardly likely to be true, but it did touch upon a point we’d both considered privately. It takes a big workforce to build thousands of miles of road, the colony had spread out to occupy all the lands that the Sets had formerly possessed, and the Sets were noted in the survey reports as being conspicuously docile. Mme. Levasseur had been very cagey about the population
