The sentence is never finished. Vernet's foot has pressed the yielding carpet; he clutches the air wildly, and disappears like a clown in a pantomine. "Now," whispers Silly Charlie, "off with your fetters, Warburton, and I will guide you out of this place. You are not entirely safe yet." Up from the trap comes a yell loud enough to waken the seven sleepers, and suddenly, from without, comes an answering cry. "It's Vernet's men," says Silly Charlie. "Now, Warburton, your safety depends upon your wind and speed. Come!" CHAPTER XVII. A PROMISE TO THE DEAD. Guided by Silly Charlie, Alan Warburton finds himself hurrying through crooked streets and dismal alleys, for what seems to him an interminable distance. Now they run forward swiftly; now halt suddenly, while Charlie creeps ahead to reconnoiter the ground over which they must go. At last they have passed the Rubicon, and halting at the corner of a wider street than any they have as yet traversed, Alan's strange guide says, "You are tolerably safe now, Mr. Warburton; at least you are not likely to be overtaken by Vernet or his men. You are still a long distance from home, however, and possibly the way is unfamiliar. I would pilot you further, but must hurry back to see how Vernet is coming out." [Illustration: "Vernet's foot has pressed the yielding carpet; he clutches the air wildly, and disappears."--page 137.] For the first time Alan Warburton, the self-possessed, polished man of society, is at a loss for words. Society has given him no training, taught him no lessons applicable to such emergencies as this. "Of one thing you must be warned," continues the guide. "Van Vernet is a sleuth-hound on a criminal secret, and he considers you a criminal. He has seen you standing above that dead man with a bar of iron in your hand--did you know that bar of iron was smeared with blood, and that wisps of human hair clung to its surface? Never mind; _I_ do not accuse you. I do not ask you to explain your presence there. You have escaped from Van Vernet, and he will never forgive you for it. He will hunt you down, if possible. You know the man?" "I never saw his face until to-night." "What! and yet, two hours ago, he was at your brother's house, a guest!" "True. My dear sir, I am deeply indebted to you, but just now my gratitude is swallowed up in amazement. In Heaven's name, who are you, that you know so much?" "'Silly Charlie' is what they call me in these alleys, and I pass for an idiot." "But you are anything but what you 'pass for.' You have puzzled me, and outwitted Van Vernet. Tell me who you are. Tell me how I can reward your services." "In serving you to-night, Mr. Warburton, I have also served myself. As to who I am, it cannot matter to you." "That must be as you will,"--Alan is beginning to recover his conventional courtesy--"but at least tell me how I may discharge my obligations to you. _That_ does concern me." Alan's companion ponders a moment, and then says: