A constable entered the room whilst Poltavo was talking, and T. B. raised his hand warningly.

"Tell me," he said carelessly, "why you have not joined them."

Then, like a flash, he brought his hand down over the transmitter and turned to the waiting constable.

"Run across to Mr. Elk's room," he said rapidly; "call the Treasury Exchange and ask what part of London—what office—this man is speaking to me from."

Poltavo was talking before T. B. had finished giving his instructions.

"Why have I not joined them?" he said, and there was a little bitterness in his voice,—"because they do not wish to have me. Poltavo has served his purpose! Where are they now?—that is what I wish to know. More important still, I greatly desire a piece of information which you alone, monsieur, can afford me."

The sublime audacity of the man brought a grin to T. B.'s face.

"And that is?" he asked.

"There was," said Poltavo, "amongst the documents you found at our headquarters in Jerez a scrap of paper written somewhat unintelligibly, and apparently—I should imagine, for I have not seen it—without much meaning."

"There was," said T. B. cheerfully.