"Perhaps we're looking in the wrong place," the captain remarked. "After all, given the tower's height, there's no telling how far down…whoa!"
"What do you think?" Lamont asked. "Does it look Martian to you?"
The approach had been slow and laborious, fighting across rough and uneven terrain in gravity that was noticeably greater than that of Earth. Finally, they had reached the base of the tower, close enough that the metallic surface of the structure occupied the entirety of their forward vision, as if they were standing before an infinitely high wall. It was not a perfect cylinder; the uniform curve of the tower was broken by several bulbous buttresses, for lack of a better term. From a distance, Lamont guessed that there were something like five of these spaced equidistantly around the circumference. The sharp, metallic rock of the moon hugged the base unevenly, as if the tower had grown up out of the moon. Like a beanstalk, he thought.
The voice of Phobos responded in his ear after a delay of several seconds. "Given the length of Martian history and the number of technological periods, nothing can be entirely ruled out," he said. "That said, I'm not seeing anything that is strongly indicative of our exploratory era."
They continued picking their way along the jagged surface of the moon until they were close enough to actually touch the surface of the structure. In space, the tower had a brassy, metallic sheen. Here, it was dark, pockmarked. During their descent toward the moon, he had never noticed an abrupt change in the material of the structure, and he guessed that what he was seeing was simply some effect of being close to the surface of the moon. He did not crane his neck to see if some difference in coloration could be perceived farther up. Some time ago, he had found that he appeared to be physically incapable of forcing himself to look up, to take in the terrible height of the thing. He knew that this was irrational, that the targeted paralysis must be something he could force himself to overcome. But, he told himself, he would probably regret it.
"Try to keep up," Carter's voice reminded him. "I want to circle the entire perimeter before the asteroid pod returns."
Lamont turned away from his inspection of the tower's surface to see Francis and Phobos following the curve of the base, nearly two hundred feet away. He rushed to catch up with them, marveling at how the captain was keeping up with the Martian's measured strides despite his obvious handicap.
"It somehow seems even larger down here than it does up there," Lamont observed breathlessly.
"It's not an illusion," Phobos remarked. "The tower is definitely tapered. I estimate the diameter at the base is twice that of the tip."
"But the length of it, combined with the perspective from which it is necessarily seen, makes it look like a uniform cylinder," Francis added. His voice, though strained by the physical effort he was making, nevertheless sounded bright to Lamont. It was lacking the somber, almost bored quality that so often typified his demeanor. "I've been keeping an eye out for anything that looks like it could be a hatch or even a distinct panel. I haven't seen anything—have you?"
Lamont and Phobos both responded with negatives.
"Perhaps we're looking in the wrong place," the captain remarked. "After all, given the tower's height, there's no telling how far down…whoa!"
Lamont was several paces behind Francis now, and he saw the older man fall sideways, the tip of his cane slipping one way while his legs went the other. In the heavy gravity, Lamont couldn't move fast enough to catch him. He and Phobos both reached the captain as he was struggling to use his cane for leverage in returning to his feet.
"Do you need to rest, Francis?" Phobos asked, with evident concern.
"It's not my leg," Carter snapped, with evident irritation. "Can't you feel that the ground is shaking?"