Ancient Shores by Jack McDevitt Page B

to a depth of more than three hundred feet.
    He checked the dates on Native Americans. They had been here early enough to have seen Agassiz. What else had they seen?
    The spruce fibers in the loops of the mooring cables indicated that the boat had been tied up rather than simply anchored. That implied a harbor. Where within a reasonable range of Tom Lasker’s farm had there been a sheltered harbor?
    Where, along the shores of Lake Agassiz, would you build a pier?
    The size of the coastline was dismaying. It stretched from north-central Saskatchewan to St. Anthony’s Falls in Minneapolis. Probably ten thousand miles of shore. Hopeless. But there was a fair chance that the boat had been moored, that it had broken loose, and that it had been driven onto a reef or sunk by a storm shortly afterward. Not a tight chain of reasoning. But it was possible. If so, then the mooring place lay in the neighborhood. Say, along the western coastline between Fargo and Winnipeg.
    He looked a long time at the maps.
    What did a good harbor need? Obviously the water had to be at the right level. That made it a problem of altitude. Okay, he could check that out. It would have to provide shelter from current and wind. And enough depth to tie up without grounding during low tide. That meant no shallow slopes. There couldn’t be too many places like that.
    He hoped.
     
    Max lifted off, climbed into a clear sky, and turned west, looking for the shoreline. He didn’t find it. The Red River Valley rises in the south, and the escarpment, which is so pronounced near the border, sinks to invisibility. From offshore, the coast would have looked flat. That meant there could have been no deep-water approaches.
    He turned north, flying over a snow-covered landscape marked by silos and occasional towns connected by long, quiet two-lane roads. The ancient coast did not appear until he crossed into Cavalier County.
    Near Herzog Dam, Route 5 passes through a cut. He went down to four thousand feet for a better look. The snowfields had been abandoned to winter, and nothing moved in all that landscape save a lone pickup, approaching from the east. It was possible the cut disguised an ancient harbor, and he flew overhead several times without coming to a firm conclusion. Unfortunately, if this was it, he doubted there would be much left to look at. He photographed it and flew on.
    He found another potential landfall south of Walhalla, off Route 32.
    And another candidate in Canada.
    Three possibilities in all.
    The site at Walhalla was closest to the Lasker farm. That one first, he thought, turning east.
     
    He called April from the plane. “No big thing,” he said. “But it’s a possibility.”
    “Sure.” She didn’t sound particularly enthusiastic. “Anything’s better than what we’re doing now. Who owns the land?”
    “I can find out, if you want me to pursue it.”
    “Yes,” she said. “Go ahead. Get us permission to look around.”
    Tom met him at Fort Moxie International. He was equally unimpressed, but he shrugged and took the same tack. “We can ride over now, if you want,” he said.
    They drove west on Route 11, past the farm, and out to the edge of the Pembina Escarpment, where they turned south on Route 32. The hills and ridges on the west side of the road formed a solid chain, with clumps of forest scattered across their summits and piles of rock at ground level. Walhalla nestled in this section, a prosperous prairie town of frame houses, lumberyards, and feed stores.
    Ten minutes south of town, the trees parted, and they were looking into a horseshoe canyon.
    “Johnson’s Ridge,” said Lasker.
    The canyon walls were rocky and almost sheer on the south and west. The northern slope rose more gradually toward the summit. It was heavily wooded, as was the valley floor. Two men were stopped just off the road, cutting firewood, stacking it in the back of a pickup.
    The canyon was two hundred yards wide at its mouth and maybe twice as