As French said these words an idea flashed into his mind, and he went on deliberately, but with growing excitement: “And when we connect the idea of a U-boat commander giving a message which ends with a sea expedition, with the fact, which I have just discovered, that the essence of his cipher is the _position_ of the markings on it, we seem to be getting somewhere.” Price smote his thigh. “By Jemima!” he cried. “I’ve got you. That blessed tracing is a map!” “A map, yes. That’s what I think,” French answered eagerly, and then as suddenly he saw the possible significance of Nelson’s exhortation, he went on dramatically: “A map of England!” Cheyne swore softly. “My word, if we aren’t a set of blithering idiots!” he exclaimed. “Of course! ‘England’ is the title. That’s as clear as day! The other words are added as a blind. Let’s have the thing out, Inspector, and see if we can’t make something of it now.” As French produced his enlarged photographs not one of the three men doubted that they were at last well on the way towards wresting the secret from the document which had so long baffled them. Chapter XIX The Message of the Tracing Inspector French spread the photograph on his desk, and Cheyne and Price having drawn up chairs, all three gazed at it as if expecting that in the light of their great idea its message would have become obvious. But in this they were disappointed. The suggestion did not seem in any way to help either French or Cheyne, and Price, who of course had not seen the document before, was satisfactorily mystified. Granted that the thing was a map, granted even that it was a map of England, its meaning remained just as provokingly hidden as ever. Presently Price gave vent to an exclamation. “Hang it all!” he cried irritably, and then: “I suppose those numbers couldn’t be soundings? Could they give depths at the circles?” “That’s an idea,” Cheyne cried, but French shook his head. “I think there’s more in it than that,” he observed. “If you examine those numbers you’ll find that they’re consecutive, they run from one to thirty-six. Soundings wouldn’t lend themselves to such an arrangement. You may be right, Mr. Price, and we must keep your idea in view, but I don’t see it working out for the moment.” Silence reigned for a few moments, then Price sat back from the table and spoke again. “Look here, Inspector,” he said, knocking the ashes out of his pipe and beginning to fill it with his strong, black mixture, “you said something just now I didn’t quite follow. Let’s get your notion clear. You talked of this thing beginning with the sea—at Schulz, and ending with the sea—at _L’Escaut_, and Schulz’s message being a map. Just what was in your mind?”