"More than that, on the New York visit Goldenburg was accompanied by a woman whose description in every particular corresponds with that of the Princess Petrovska--though she called herself the Hon. Katherine Balton. There is material enough in that information, Sir Hilary, to draw a number of conclusions from. At any rate, they go to confirm my opinions at present. I know very well that there is sometimes smoke without fire, but my experience is that you can usually safely lay odds that there is a fire somewhere when you do see smoke." The elliptic form of speech was sometimes adopted by Heldon Foyle in discussing affairs with one whose alertness of brain he could depend upon. Thornton twisted his grey moustache and his eye twinkled appreciatively. "That's all right," he said. "But how do you account for Grell finding people ready to his hand in London to help him disappear at the very moment he needs them? There are several people mixed up in it, we know; but how is it that they are all loyal to him? We know that criminals will not keep faith with each other unless there is some strong inducement. How do you account for it?" "There may be a dozen reasons. Purely as an hypothesis, Grell may have a hold on these people by threatening them with exposure for some crime they have committed. Self-interest is the finest incentive I know to silence." "All the same, it's queer," said Sir Hilary, with a little frown. "What do you propose to do?" Heldon Foyle's lips became dogged. "Break 'em up piecemeal as we lay our hands on 'em now. We've got one--the man we roped in with Red Ike. He's as tight as an oyster; but while we've got him he can't do anything to help his pals. Then there's the Princess. She's as slippery as an eel; but if the Liverpool people can get hold of her we may reckon she'll be kept safe for a few weeks on the charge of drugging Blake. Then there's Ivan Abramovitch. We may be able to lay our fingers on him. If there's any more in this business I don't know 'em; but every one of the gang we take means so much less help for Grell." A discreet knock at the door heralded the entrance of a messenger, who laid an envelope on the table and silently disappeared. "Western Union," muttered the superintendent. "This may be something else from Pinkerton's, Sir Hilary. Don't go yet." And, tearing open the envelope, he crossed the room and pulled down a code-book. In a little he had deciphered the cable. "We're getting closer," he said. "Pinkerton's have got hold of 'Billy the Scribe,' who identified the photograph of the dagger with which the murder was committed as one that he believes was in the possession of Henry Goldenburg when he last saw him. That may be fancy or invention, or it may be important. Hello! what is it?"