Yet there was no evidence of any attack. If Sokolsky was as light a sleeper as he claimed, any mouthing of their suits would have wakened him.
Chuck shrugged and tried to forget it. He made an unsavory meal out of the cubed concentrates Sokolsky had put in the little hopper under his chin. At the press of a lever, one cube would be popped up where he could get it. The tube that supplied water was also within reach, but he used that sparingly since it had to moisten the desiccated Martian air as well as supply his thirst. A final check showed him that there was considerable life left in the batteries that powered the air compressor.
Sokolsky was muttering unhappily to himself as they began the journey toward the mysterious canal. It still puzzled him that an animal should steal an automatic.
Then he brightened. “But there is the example of the magpie. It steals for no good reason. Several other animals do. And there is no way of telling what might smell—if they do smell—good to a Martian animal. Of course.”
Chuck smiled. Now that there was an example with which to compare it, Sokolsky was happy again. He was even whistling under his breath as they tramped along. Suddenly Chuck stopped, staring at the ground. “Doc!”
“Eh? Oh, you’ve found something.”
It was part of a footprint—or pawprint. There were four toelike members, the two outer ones smaller than the inner ones; behind that, there was part of the ball or heel of the foot. It looked about half the size of a human footprint.
“At least four-toed—and from the symmetry, it must be four-footed. Wish the back weren’t hidden or obliterated.” Sokolsky studied it with rapt attention. “Very interesting, though it doesn’t really tell us anything. If there were several of them, we could estimate the number of feet, the weight of the animal, and a number of other details. But this is only one, and incomplete. Still, it’s interesting to note that nature has evolved the toed foot here on Mars.”
There were a number of plant forms that neither had seen before, including one bigger one, something like a head of cauliflower, but with thicker leaves, and about the size of a large cabbage. This one was a dark purple color instead of the usual green. There were several others like it. Sokolsky inspected them carefully, and grinned with satisfaction. “Also three-sexed, though of a greatly different species. It would seemingly be safe to guess that all Martian plant life depends on two pollinators and a single incubator.”
Two more hours went by, and Sokolsky began to fret and worry again. He seemed to be able to maintain his calm doctor’s role as long as he liked, but to go suddenly off on a wild emotional tear as soon as he decided he was a biologist.
“The canals should be here. Rothman said it was about thirty miles north, didn’t he?”
Chuck nodded. “We’ve come somewhere between twenty-five and thirty. We may be short of it by several miles.”
Sokolsky agreed, but he didn’t look happy. He quickened the pace and went forward at almost a run. Chuck’s legs were still sore from the grueling week of work, but he had to stick with the doctor.
They came to a slight rise in the ground and surveyed the country beyond them. There was certainly no sign of a deep trench of any kind, nor of an old river bed, etched out in the billion years ago when Mars might have had water.
But Sokolsky’s eyes brightened. “See? There’s a darker streak. That must be it.”
Again he quickened his pace, and Chuck had to force himself along. But they were less than two miles away, and the space was quickly covered. Sokolsky pointed suddenly, and ran forward while Chuck stared around in an attempt to see what had drawn his attention.
He could see nothing except a great mass of plants with thick leaves about the size and shape of pumpkin leaves. But these were waxy and smooth instead -of rough, and they were of such a dark green color that they almost appeared black in the distance.
“Where’s the canal?” Chuck asked.
Sokolsky pointed to the plants. “Right here. Chuck. The best explanation I could ask to the old mystery, too. Look at them.”
Chuck moved forward until he was standing among the plants. They were peculiar. Lying along the ground, and connecting each plant to the next in line was a grayish rootlike tube. Crosswise, there were smaller, dark green filaments. But the straightness of the tubes and the exactitude with which they spaced themselves out caught Chuck’s attention. They looked like little rows of laundry lines, with the leaves for laundry. Or perhaps they were like the rows of telegraph poles he had once seen.
“Perfectly straight,” Sokolsky commented. “Look up there as far as your eye can see—no, get your head in line with one of the plants. Now look. What do you see?”
“A practically perfect row of plants—and I suppose they’re all connected together this way.”
“Apparently. Here, cut one of them.”
Chuck bent down and pulled his knife from his pouch. The connecting tube was hard and tough, but he finally sawed through it. Three drops of thin liquid oozed out. “One of the first cases of a plant on Mars which secretes fluid,” Sokolsky told Chuck. “Now, watch what’s happening.”
The tube had contracted, sending a ripple back from each cut toward the mother stem. It reached, and a second later the broken halves of the tubes fell off. There was a small bud on the northern plant where the tube had been; on the southern one, there was a faint indentation.
“You see,” Sokolsky gloated. “They connect. Cut a tube, and it is drained, then discarded. And a new one will grow from this bud to the Opposite little socket. Chuck, what did Lowell think the canals were?”
“Just that—canals, built to carry water from the icecaps at the poles to the rest of the planet when the caps melt in the spring.”
“And here you have it—perhaps. See, they run in a straight line—I don’t know how wide, but it must be for miles here—as far as we can see. Each of those tubes-carries a bit of water one plant farther. It’s a regular canal system, Chuck—with a pumping station every two feet, wherever a plant stands. And notice how the foliage differs from other plants here—it would probably photograph enough differently to give just the effect the canals do give.”
Chuck stared up the line, and down again. So far as he could see, the plants were in perfectly straight order.
He turned away, disappointed. “I guess I’m a sucker, doctor, but I kind of hoped the canals might turn out to be the work of intelligence, after all.”
“And how do you know they’re not? Is it impossible for these plants to have intelligence? Could men design a better and more efficient system to distribute the tiny amounts of liquid which accumulate at the poles—a snow-cap only an inch or so deep, which only wets the ground when it melts—and yet which these plants may spread to their own kind over the whole planet?” Sokolsky stood admiring them. “A perfect answer to a mystery, and a perfect example of either intelligence or adaptation. I don’t know which.”
“But it isn’t the kind of intelligence I meant, and you know that,” Chuck protested.
“You mean animal intelligence, preferably like humans, of course.” Sokolsky pondered it, turning to stare across the great “river” of plants, and back to the land around. “I don’t know. We may never know the answer to that.”
“Why?”
“Well, look. Notice that the land is lower here—we came over a ridge, into a hollow to find these; across there, it seems to be the same way. And it’s the same as far as we can see. Maybe these are old river beds—though why they should be as straight as even the most crotchety astronomer admits, I don’t know. Maybe they are channels dug up by some race that lived here. Maybe the plants are something they grew to meet the dwindling water supply.”