"Lost your man!" was his greeting. And it wasn't a question; it was a statement. "How did you know?" I growled. My humiliation was too fresh to stand kidding. "Constantinople," said Foulet amiably. "You always lose them in Constantinople. I've lost three here." "Three?" I said, "Like mine!" "Exactly," he nodded. Then he lowered his voice. "Come to my hotel. We can talk there." "Now," he continued fifteen minutes later as we settled ourselves in his room, "you were very circumspect in Paris. You told me little--just a hint here and there. But it was enough. You--the United States--have joined our ranks--" "You mean--" "I mean that for a year we, the various secret service organizations of the Continent--and that includes, of course, Scotland Yard--have been after--Well, to be frank, we don't know what we're after. But we do know this. There is a power--there is someone, somewhere, who is trying to conquer the world." [Illustration: _A white speck took shape beneath the rising Island._] "Are you serious?" I glanced at him but the tight lines of his set mouth convinced me. "I beg your pardon," I murmured. "Go ahead." "I don't blame you for thinking it was a jest," he said imperturbably, "But, to prove I know what I'm talking about, let me tell you what this man has done whom you have been pursuing. He has done one of two things. Either he has proved himself a dangerous revolutionary or he has engineered the failure of a bank or chain of banks--" "We can't prove it," I interrupted. "No," said Foulet, "Neither can we. Neither can Scotland Yard--or the secret services of Belgium or Germany or Italy or Spain. But there you are--" "You mean that in all these countries--?" "I mean that for a year--probably longer--these countries have been and are being steadily, and systematically, undermined. The morale of the people is being weakened; their faith in their government is being betrayed--and someone is behind it. Someone who can think faster and plan more carefully than we--someone whose agents we always lose in Constantinople! I'll wager you lost your man from a roof-top." I nodded, my disgust at my own stupidity returning in full force. "There was a lower roof and a maze of crisscross alleys," I muttered. "He got away." "Was there an airplane anywhere around?" asked Foulet. I glanced at him in surprise. What good would an airplane have been on a roof-top ten feet wide by twelve feet long? Then I remembered. "There was an airplane," I said, "but it was a long way off, and I could scarcely see it; but the air was very still and I heard the motor." Foulet nodded, "And if you had had a pair of glasses," he said gently, "You would have seen that the airplane had a glider attached to it. There is always an airplane--and a glider--when we lose our men from the roofs of Constantinople." "But that must be coincidence!" I insisted. "Why, I was on that roof right on the fellow's heels--and the airplane was at least five miles away!"