"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?"