Hudson contemplated her logic. "You might have a point, Sharl. But I bet we have to pay it back somehow. You don't get something for nothing."

"Even the months are longer," Buccari remarked, "assuming you use the big moon as the reference. It takes thirty-two days between full moons."

"Actually the little moon might be more convenient," Hudson said, throwing the rock into the lake. "Takes fourteen days to cycle. We double the period and have a twenty-eight day moon month just like on Earth. Whatever, it's sure nice to have long summer days."

"Let's see how we feel after spending a winter here. A winter like we've never seen. We need to get off this plateau."

The patrol halted at the rise next to the cliff edge. MacArthur wiped perspiration from his forehead and looked up to see cliff dwellers soaring across the cloudless sky. Two creatures glided much lower than the others. He slipped off his pack, unzipped a side pocket, and pulled out a small notebook.

"Now what do we do?" Petit asked.

"We leave this," MacArthur said. "Gotta' find the mailbox." "Let me see the book, corporal," Quinn ordered.

"Yes, sir," MacArthur said as he handed it over. He watched the commander carefully. The skipper had been moody since leaving the camp. "Lieutenant Buccari and Mr. Hudson did a really good job, sir."

"Looks like a comic book," Petit said, looking over Quinn's shoulder.

"From the mouth of an expert." MacArthur laughed. "What's that supposed to mean?" Petit snarled.

"Just a joke," MacArthur said, smiling.

"Why ain't I laugh—?"

"Cut it out, you two," Shannon ordered, walking back from the plateau's edge. Shannon's moodiness since leaving camp had been no less heavy than the commander's.

"That's about what it is—a comic book," Quinn said, breaking the tension. "Lieutenant Buccari doesn't think we'll ever be able to speak their language, or they ours, so she prepared this notebook of icons and cartoons as a first step in communications."

"It looks like they aren't accepting deliveries," Shannon remarked.

"Lieutenant Buccari said we should put up a cairn of rocks, seal the book in a utility pouch, and leave it," MacArthur said. "What do you think, Commander?"

"Do it," Quinn replied, handing the book back. "Let's get going. I'm anxious to see this valley you and Chastain keep talking about."

Their task completed, the patrol moved along the jumbled cliffside, stopping to fill their canteens in the river.

"Trail starts over here," MacArthur said, looking out over the dizzy traverse. The river crashed over the precipice behind them. They descended the narrow ledge, hugging the cliff wall for the rest of the day. At last the trail flattened and mercifully turned away from the river gorge, providing a place to make camp. In the twilight MacArthur looked out across the plains to the twin volcanoes in the distance, still far below his elevation.

Morning came quickly and was pleasantly warmer than the frosty plateau mornings, promising a hot day. After a long morning of dusty, downhill hiking, the patrol came to a thinly forested tree line; there the trail switched back to the northwest, descending sharply to the river. MacArthur noticed a narrow valley on the opposite bank. Below them the powerful watercourse jogged sharply to the north, necking down to a turbulent constriction.

"Chastain and I intercepted the trail up higher," he said, relaxing in the sparse shade of some firs. "I haven't seen any of this."

"Options?" Quinn asked, looking down the steep trail.

"The valley is three days from here, downstream," MacArthur said. "If we stay high, it's downhill all the way. If we go down this trail to the river, we'll have some serious climbing later on."

"What do you think, Sergeant?" Quinn asked. "Do we follow this path and see if it tells us anything, or do we head for MacArthur' s valley?"

"We should check out the neighborhood," Shannon said.

Quinn pointed downhill. MacArthur pushed off without further discussion. As he made his way down the steep path the corporal glanced into the blue skies and saw two motes circling high overhead.

"We're being watched," he said, pointing out the flyers.

"You think they got Lieutenant Buccari's book?" Shannon asked.

"You think they can really read?" Petit asked. "They're stupid animals."

"You can read, can't you?" MacArthur chuckled. "Sort of?" "Bite my—"

"I told you to cut it out," Shannon snapped. "Especially you, Mac."

"Sorry, Petit," MacArthur apologized. "But someone patched me up, and if it ain't those ugly buggers, then something else lives up there."

Petit grumbled an acknowledgment.

"Let's move," Quinn ordered, taking the lead.

The rocky trail fell precipitously as it reached toward the river, switching back and forth across the face of the gorge. MacArthur saw the bridge long before the patrol reached it. Shrouded in river mist, the bridge spanned the river at its darkest and narrowest point, reaching almost two hundred meters in length. At its lowest point the bridge was fifty meters above the frothing white torrent. Upstream, at a level higher than the bridge, the river crashed over tall cataracts, throwing thick mists into the air, obscuring the view and making conversation impossible. Downstream, swirling waters careened between the gorge walls, swinging to the north and out of sight.

The immensity of the plateau was even more spectacular from this lowest of vantage points. Rock walls mounted vertically, their imperceptible slant exaggerating a sense of infinity with incredible perspectives. The sun, just past its zenith, was already setting behind towering cliffs, and river mists fractured the rays of light, sending improbable rainbows across the chasm.

MacArthur again detected two cliff dwellers gliding through the mists, heading for wet rocks above the bridgehead on the opposite side.

"Suspension…chain link…!" shouted Quinn over the river's roar.

MacArthur examined the fist-sized links and followed the converging and diverging catenaries of the support cables as they swooped down from the cliffs on either side of the river. Parallel chains came out of the bedrock at his feet, forming a narrow bridge bed. Wooden treads, slick with moisture, were firmly attached at half-pace intervals, presenting more open space then floor. The view of the roiled water through the bottom of the bridge was unnerving.

MacArthur checked the chain cables for corrosion but found only traces of oxidation. Some of the mist-chilled and dripping links appeared newer than their neighbors, as if they had been replaced. The workmanship was rough and unpolished, but the individual links were well forged and continuous. He placed a foot on the first tread and tentatively tested his weight. The bridge was solid. MacArthur walked across, gingerly avoiding a misstep into the tread gaps. The others followed, one at a time. The river below served notice of its power, not that MacArthur needed reminding.

Once across there was no place to go but to follow the trail. It tracked upstream along the steep cliffside of the opposite bank for a hundred paces and then climbed sharply to a point where the rock wall of cliff plunged sharply to meet it. Reaching the bottom of the vee, they found themselves in the narrow valley observed from the heights of opposite bank. The trail leveled and meandered upward, traversing the valley's steeply sloping sides, making for a distant point at the head of the valley. Small stands of yellow-barked fir sprinkled the vale, but for the most part, the rock-strewn valley was devoid of vegetation.

They walked through the afternoon, stopping next to a rock-bottomed brook that defined the fall line. The trail leveled, and intermittent patches of taiga prairie grew larger and more continuous. Behind them the plateau was undiminished—a ziggurat hanging high over their heads. Craning his neck, MacArthur turned to scan the massif, subconsciously taking a step rearward. Upstream, the face of the plateau curved gracefully away until it presented its profile, revealing the irregularity of its surface. Terraces, overhangs, prominences and craggy pinnacles ranged along the silhouetted granite.