“If you happen to be in Paris late at night, squire, and a rough-looking customer asks you the time or begs for a match, you'd better look out for his friend—le Père François, they call him—who may be coming up behind you with a long strip of flannel in his hand. While the first man holds you in talk, the Père François lassoes you with his flannel rope and pulls the two ends so that it catches your throat. Then he sinks down suddenly and turns his back to you, slipping the rope over his shoulder as he turns. This pulls you down back to back with him; and when he rises to his normal height again, there you are on his back like a sack on a coal-heaver's back, with your feet off the ground. The first man then goes through your pockets at his leisure, and if you choke to death before he's done, so much the worse for you. You can't struggle with any effect.
“That I suspect, was how they caught friend Paul; and Aird just carried him on his back to the quicksand and dumped him in. From Aird's footmarks it was clear he'd been carrying a heavy weight; the prints were deep and the feet almost parallel after he'd done his Père François trick. See now what I meant by ‘Get off the Earth’? Naturally there were no signs of a struggle, since all the struggle was off the ground. And, of course, they'd take care to wear shoes that left no clue—common type and largest size. And they got away either in a boat or by wading along in the water, so as to leave no tracks. I could see no way to bring the affair home to them. The only sure method depended on our wringing evidence out of one of them somehow; and I didn't see how it could be managed just then. Also, I hadn't much of a case against Cargill beyond suspicion; and I wanted him too, if it could be managed.
“The next thing was the arrival of the Fordingbridge lawyer; and from him I learned that we might get on the track of any malversations by Friend Paul if I went up to London. I wanted to know definitely where I stood in that matter, because, if I was wrong there, then the whole latter part of my notions would collapse. So I made up my mind to go to town.
“But I was very uneasy. Now that Paul Fordingbridge was out of the road for good, Mrs. Fleetwood was the only person between the claimant and the cash. If she disappeared in her turn, then Miss Fordingbridge would have welcomed her long-lost nephew with pure joy and gratitude for his preservation, and there would have been no one left alive to object to his coming into Foxhills and the rest. Therefore, I was inclined to take some steps to see that she came to no harm while I was away.
“The obvious thing to do would have been to warn her. But that would have meant giving my case away to the Fleetwoods; and I don't feel inclined to chuck confidences around if it can be avoided, as I've pointed out before. Further, the police were not altogether in good odour with the Fleetwoods; and I wasn't sure if I'd make much impression on them by a mere warning, with nothing to back it. So I hit on the notion of putting a man on to watch Mrs. Fleetwood; and, as a further precaution, I fixed up that code-wire so that if I wanted it I could have her arrested at a moment's notice, and then she'd be safe in police hands and out of reach of the gang.
“I went up to London and found, as I'd expected, that friend Paul had been playing ducks and drakes with all the securities he could handle without exciting too much suspicion. He seems to have been speculating right and left, most unsuccessfully. So I'd been right about his motives, anyhow.
“But I couldn't get out of my mind the risk I was letting that girl run; and at last—I suppose Miss Fordingbridge would say it was telepathy or something—I got the wind up completely, and wired to have her arrested. After that I felt safer.
“As you know, they'd been too quick for me. They fished out the note that Paul Fordingbridge wrote to the claimant and they sent it to her as if it came from Paul himself, after altering the hour on it. She thought her uncle was in trouble; went to help him; dodged the constable; and fell straight into the trap they'd set for her. You know all the rest. And probably by now you understand why I was quite content to let Mr. Aird have his full dose in the funnel of the souffleur. There's nothing like a confession for convincing a jury, and I meant him to hang if it could be managed. I didn't want to run any risk of his getting off merely because it was all circumstantial evidence.”
“Thanks,” said Wendover, seeing that the chief constable had finished his outline. “To quote from that favourite detective story of yours:
In one moment I've seen what has hitherto been
Enveloped in absolute mystery.