"Hop, skip, and a jump."

The Coast Guard officer turned out to be a fresh-faced young lieutenant with an M-16 over his shoulder, plus webbing with ammunition. He hopped nimbly from the ship's boat to the right float of the seaplane, and offered a hand all around as he slid into the other rear seat, putting the assault rifle between his knees. He had a camera, too, something better than the Polaroid Cofflin had brought.

"Lieutenant William Walker," he said; there was a Western twang to his voice, and he looked like a younger version of the Marlboro Man, square-jawed and handsome in a boyish way.

No, Cofflin thought. He looks like… what's that guy's name… Redford, yeah.

"Happy to meet you."

"Can't say as I'm too happy about anything, at the moment," Cofflin said with a dry smile, shaking his hand. It was hard and felt extremely strong. "But welcome aboard." He nodded at the assault rifle. "See you came prepared."

Walker chuckled. "The sum total of the Eagle's armament, if you don't count the flare pistol," he said. "I notice…" He nodded at the shotgun in turn.

Conversation died away as they accelerated, throwing up spray from the floats. "Water looks odd," Toffler commented as they lifted and circled the windjammer, then headed for the mainland. "And what the hell's that?" He indicated a silvery patch below.

"Take a look," Cofflin said.

The plane banked and slid down, swooping; not all Toffler's fighter-pilot reflexes had gone the way of his hair. They leveled out and made a pass with the floats nearly touching the water, the heavy salt smell filling the cabin. And not only salt.

"It's fish," Cofflin said, wrinkling his nose. "Dead fish. Damn, but there's a lot of 'em." Seagulls swarmed around the massive shoal, diving and pecking.

"Cod," Lieutenant Walker said, peering out through binoculars. "Thousands and thousands of cod, big cod."

Cofflin grunted skeptically. There hadn't been concentrations of codfish like that around New England waters for… then he remembered what Rosenthal had told him, and shivered.

"What killed them?" he said, trying to lose awe in practicality.

"There's a curving mark in the water," the astronomer behind him said suddenly. He started a little; she hadn't spoken much since the airport. "See, you can follow it." Different shades of blue, and a crosshatching of waves.

The Coast Guard lieutenant used his binoculars. "The lady's right. It's the edge of a circle, a very big circle, or at least some geometric figure. Like the effect you get with a river estuary emptying into the sea, or two very distinct currents… I've never seen anything quite like it, though. Like two different bodies of water just starting to merge."

"Never seen anything like it. That's something we're all getting used to saying," Cofflin said dryly. He clicked on the radiophone and relayed the information to the Eagle.

"Could you fly along the edge of the phenomenon for a few miles?" Alston said. "I'd like to get a radius."

"Good idea." He handed the radiophone to Walker, who called the data to his commander.

A few minutes later she answered: "Got that. Just a second… Not a circle. It's pretty well a precise ellipse, centered somewhere on the island. Not an exact distance in miles or kilometers, though-something like twenty-three point four miles across and five in height. We were just inside the edge of it, then."

Cofflin grinned humorlessly at the tinge of bitterness and took the radiophone. "Bad luck for you, Captain-but good for the rest of us, I think. We're heading in to the coast now."

"You folks know something that I don't?" Toffler said. Sweat shone on his forehead and the high dome of his head, and the Kentucky accent was stronger.

"Fill him in, Ms. Rosenthal," Cofflin said wearily.

The fact of what had happened was beginning to sink in now, and it left silence in the wake of the astronomer's hesitant voice.

"The… the transition event must have included a body of water around the island," she finished. "That's what we're seeing here. There would be differences in temperature, salinity, and so forth. Perhaps the fish were caught at the, um, interface. It looked electrical and it affected our electronic apparatus. Where it met the water, I think it electrocuted some of the sea life."

The floatplane flew low, a few hundred feet up, over intensely blue ocean just rough enough to show whitecaps; the sky was clear but a little hazy with high cloud. After a few minutes, Toffler tipped one wing and spoke:

"Thar she blows."

Cofflin shaped a silent whistle. Thar she did, in twin-tailed spouts. He'd never in his life seen that many whales; the spouts and glistening backs stretched for miles. "Big pod," he said expressionlessly. "Right whales. Blackfish."

Which had been virtually extinct in these waters since the eighteenth century.

By the time they overflew a Cape Cod empty of roads and houses and reached Boston, he was almost unsurprised at what they found. There was still a bay and islands, but only roughly like the maps. Dense forest grew almost to the water's edge, huge broadleaf trees towering hundreds of feet into the air, and birds rose in their tens of thousands from salt marsh and creekmouth, enough to make the pilot swerve. Toffler circled for a few minutes, aimlessly. What clear spots there were on dry land looked to be the result of old forest fires. Under his numbness Cofflin thought how beautiful it was, with an unhuman comeliness that made Yosemite look like a cultivated garden.

"Well," he said, "I think you were right, miss." Rosenthal nodded and sneezed into her Kleenex.

Walker pointed. "There."

A stretch of shingle beach edged a seaside clearing where a creek ran into the sea. In it were a score or so of shelters made by bending saplings into U-shapes, and then covering the sides with bark and brush, like Stone Age versions of Quonset huts. Fires trickled smoke, and human figures pointed upward. When the plane came lower overhead they scattered like drops of mercury on dry ice; a few pushed big log canoes into the water and paddled frantically away along the shore. Lower, and they could see a woman turn back, scoop up a crying infant, and scuttle for the edge of the woods with the child in her arms.

"Can you take us down there, Andy?"

"Sure," the pilot said. "Water's calm, and that looks like a sloping surface-I should be able to ground the floats."

The seaplane turned into the wind and sank. There was a skip… skip… skip sensation as the floats touched; the airplane surged forward, then sank back to a slightly nose-up position as Toffler turned it toward the shore. Cofflin cracked the door and looked down.

"Sand and gravel… getting shallow, any minute now…"

Toffler killed the engine and the plane coasted forward. The aluminum of the floats touched bottom; they slewed about slightly and stopped. Cofflin picked up his shotgun and stepped down, onto the float and then into knee-deep water. He wiped his brow.

"Hot for March," he said, looking inland.

Walker followed him, using his binoculars again. "Can't see any of the… Indians, I suppose. Looks like they've cleared out."

"Wouldn't you?" Toffler asked. "Let's get the plane secured. We need to stake down some lines."

The men occupied themselves. Rosenthal took some items from her backpack and fiddled with them. "You're right, Chief Cofflin. It's eighty Fahrenheit." That was unusual for Massachusetts in early spring. "And look at the trees, the other vegetation."

Cofflin straightened up and did. "Season's pretty far along," he said. "But how do we know it's March?"

"I worked on my calculations," she said. "It's March, all right. Early spring, at least, but I'm morally certain it's the same day, down to the hour, that it, ah, would have been. Sunrise was at exactly the right time." She paused. "The climate may well be in a warmer phase."