He gestured to the Survey private at the stern of the boat. "Closer in, please." Barnes said: "Sir, motorboats are forbidden inshore. The vibrations." Bordman shrugged. "We will obey the rule. I've probably samples enough. How far out do the mudflats run, at the surface?" "About two hundred yards at the surface, sir. The mud's about the consistency of thick cream. You can see where the ripples stop, sir." Bordman stared. He turned his eyes away. "Er--sir," said Barnes unhappily. "May I ask--?" Bordman said drily: "You may. But the answer's pure theory. This information will do no good at all unless all the rest of the problem we face is solved. However, solving the rest of the problem will do no good if this part remains unsolved. You see?" "Yes, sir. But the other parts seem more urgent." Bordman shrugged. There was a shout from a nearby boat. Men were pointing ashore. Bordman jerked his eyes to the shoreline. A section of seemingly solid ground moved slowly toward the water. Its forefront seemed to disintegrate, and a slow-moving swell moved out over the rippleless border of the sea, where mudbanks like thick cream reached the surface. The moving mass was a good half-mile in width. Its outer edge dissolved in the sea, and the top tilted, and green vegetation leaned down-wind and subsided into the water. It was remarkably like the way an ingot of non-ferrous metal slides into the pool made by its own melting. But the aftermath was somehow horrifying. When the tumbled soil was all dissolved and the grass undulated like a floating meadow on the water, there remained a jagged shallow gap in the land-bank. There were irregularities: vertical striations and unevennesses in the exposed, broken soil. Bordman snatched up glasses and put them to his eyes. The shore seemed to leap toward him. He saw the harsh outlines of the temporary cliff go soft. The bottom ceased to look like soil. It glistened. It moved outward in masses which grew rounder as they swelled. They flowed after the now-vanished fallen stuff, into the water. The top-soil was suddenly undercut. The wetter material under it flowed away, leaving a ledge which bore carefully tended flowering shrubs--Bordman could see specks of color which were their blossoms--and a brightly-colored, small, trim house in which some family had lived. The flow-away of the deeper soil made a greater, more cavernous hollow beneath the surface. It began to collapse. The house teetered, fell, smashed. More soil dropped down, and more, and more. Presently there was a depression, a sort of valley leading inland away from the sea, in what had been a rampart of green at the water's edge. It was still green, but through the glasses Bordman could see that trees had fallen, and a white-painted fence was splintered. And there was still movement.