We gazed at Bensersiel in silence.

“There can’t be anything here?” I said.

“What can there be?” said Davies.

“What about that dyke?” I said, with a sudden inspiration.

From the bank we could see all along the coast-line, which is dyked continuously, as I have already said. The dyke was here a substantial brick-faced embankment, very similar, though on a smaller scale, to that which had bordered the Elbe near Cuxhaven, and over whose summit we had seen the snouts of guns.

“I say, Davies,” I said, “do you think this coast could be invaded? Along here, I mean, behind these islands?”

Davies shook his head. “I’ve thought of that,” he said. “There’s nothing in it. It’s just the very last place on earth where a landing would be possible. No transport could get nearer than where the Blitz is lying, four miles out.”

“Well, you say every inch of this coast is important?”

“Yes, but it’s the water I mean.”

“Well, I want to see that dyke. Let’s walk along it.”