They ascended to the cloud. At five thousand meters Lyra was having some trouble breathing, though this was due more to the unaccustomed exertion than the altitude. Due to the denser atmosphere, five thousand meters on Tslamaina was equivalent to thirty-five hundred meters or so on Terra.
As they crested the trail head, the clouds momentarily parted. Ahead rose the peak of a steep-sided mountain that towered above them and the nearby edge of the Guntali. As they rested, Etienne took a sighting on the peak.
“Eleven thousand meters, most of it frozen.”
“Aracunga,” Tyl said. Etienne noticed that all the Tsla now wore their sturdiest clothing. They stood some two thousand meters higher than Turput, at the upper limit of the Tsla ecological zone. They could climb higher still, but not comfortably.
After several days of climbing to the east, they set off northward. Etienne expected Tyl to continue in that direction, but he was wrong. On the second day they turned slightly to the west, and by that evening the Redowls could feel thunder again.
They expected another waterfall, perhaps one that plunged the full five thousand meters to the river below. But it was no waterfall Tyl led them toward. It was the Topapasirut.
Must be the father of all waterfalls, Etienne mused, still unconvinced by Tyl’s denials. By the fourth day the thunder had become so loud they could communicate only by signs.
The Redowls could tap out messages on their wrist computers, but the Tsla possessed no such wondrous devices and had to make their intentions known through gestures. It grew damp around them, the rocks treacherous and slick. Yet as they hiked now through the perpetual mist, the sky overhead remained clear.
Etienne searched in vain for signs of the expected cascade. When they finally reached the lip of the abyss, all was explained.
It was raining upward. Forced into a narrow throat of the Barshajagad, the entire volume of the Skar suddenly made a sharp and unexpected bend from south to west. As a result, the swiftly flowing river cannonaded into the north cliff face that formed the base of the mountain Aracunga, five thousand meters below their feet.
This produced a spray that rose on disturbed air to drench the puny observers clinging to a granite overhang. The solid bedrock trembled under the river’s impact. Tyl communicated with gestures, but any description was superfluous before the stupendous sight below.
Etienne knew that this was the Topapasirut, the birthplace of all river devils. He knew that Tyl had been more than right when he’d insisted no boat could pass through this place. The hydrofoil could not rise high enough on its repellers to clear the maelstrom.
Across the canyon, rising from the opposite side of the abyss, was a metamorphic mass that dwarfed even Aracunga.
“The Prompaj!” Tyl screamed into Etienne’s ear. He took another sighting.
“Fourteen thousand two hundred meters,” he informed Lyra via wrist computer. “An impossible mountain. I think the two peaks were once closer than now. See how the river bends sharply to the west before turning south again? Tslamaina’s seismically stable now, but a few eons back there must have been one hell of an earthquake in this part of the world. See the signs of slippage?” He pointed to particular strata down in the roaring canyon.
“This section of the surface slipped eastward. South of here the land went west. The result was the displacement of the northern third of the Skar several kilometers to the east. I’m glad I wasn’t around then.”
Lyra tapped out a reply. “I’m not real happy to be here now. Let’s get away. I’m cold and wet.”
They lingered a few moments longer so he could chip a few more pictures, take some final measurements. Then they headed back toward the trail head, leaving the clouds and hillsides to swallow up the Topapasirut, its thunder, and the brooding massif that was called Prompaj.
They made camp that night in a small cave, drying themselves and their clothes before a large fire. Etienne watched with interest as the porters groomed each other’s fur.
The Redowls said little. There was no point in belaboring the obvious. Their expedition had reached its end. They’d run up against not a brick wall but a watery one.
When the porters had finished and dressed themselves once more they gathered close around the warmth of the fire. Tyl spoke while his companions ate.
“What will thee do now, Learned Etienne? Does the spirit boat possess some magical power we have not seen that would enable it to pass through the Topapasirut?”
“It does not,” Etienne replied glumly. “We do have other machines which can fly through the air and put any bird to shame, but we don’t have one here. We chose to travel by boat. It’s all we have. You were right, Tyl. I apologize for doubting you.”
“You had not seen the Topapasirut, Etienne. No one believes until they have seen.”
“That’s it, then.” Lyra was not as disappointed as her husband, though she strove to sound as sympathetic as possible. If they could no longer go onward, they would have to go back, and she still had work to do among the Tsla.
“You’ve been stopped by a geological phenomenon, Etienne. What better way to conclude your report? Think of the reaction among your colleagues when you describe this place. Maybe someday we can come back up here with an aircar.”
He’d been staring at the floor of the cave. Now he looked up, determined. “They’ll be fascinated, but it won’t be the end of my report.”
“Etienne,” she said gently, “we can’t get through that chute. You’ve already acknowledged that.”
“I won’t be stopped by the very river I’ve come to survey.”
She sighed, leaned back against the inflated sleeping pad. “Maybe you’ll accept it by morning.”
“Maybe.”
He did not, nor did he admit defeat during the long descent to the Skar. He kept to himself and brooded, causing Tyl to move next to Lyra.
“What ails Etienne?”
“He’s unhappy because he knows we can’t go on. That means he’ll have to leave his work here unfinished.”
“But it is not his fault. Nothing passes Upriver beyond the Topapasirut. He has no control over that. It is not as if he were beaten by something in himself.”
“He knows all that, Tyl, but he is persistent, Etienne is. Always has been.”
“I see. A Tsla teacher would accept the inevitable; such constant worry is harmful to the mind.”
“True, but sometimes it can lead to solutions where none seem possible. I’ve seen him do it before. Within our fields, Etienne and I are well respected. We’ve achieved success where others have failed. It’s one of the reasons we were allowed to make this expedition while other applicants were rejected. Sometimes, Tyl, blind persistence can succeed where everything else has failed.”
“I still do not understand why you would sacrifice peace of mind. I can admire such tenacity, but I cannot empathize with it.”
Down on the river there was a brief but joyful reunion with those left behind. Homat didn’t try to conceal his relief over the safe return of his human protectors.
