that suggested the means of death? In either case,
when he nailed up his letter-box, it was not, of course, to keep the
postman from the door, but to keep the smell of gas inside if he or
anybody else did come. That, I think, is fairly plain."

"It's ingenious," I conceded, "whether the idea's your own or Royle's."

"It must have been his," said Delavoye with conviction. "You don't
engineer an elaborate fake and get in one of your best bits by accident.
No; there was only one mistake poor Royle made, and it _was_
unpremeditated. It was rather touching too. Do you remember my trying to
get something from his fingers, just when the knock came?"

I took a breath through my teeth.

"I wish I didn't. What was it?"

"A locket with yellow hair in it. And he'd broken the glass, and his
thumb was on the hair itself! I don't suppose," added Delavoye, "it
would have meant to anybody else what it must to you and me, Gillon; but
I'm not sorry I got it out of his clutches in time."

Yet now he could shudder in his turn.

"And to think," I said at last, recalling the secret and forgotten
foreboding with which I myself had entered the house of death; "only to
think that at the last I was more prepared for murder than suicide! I
almost suspected the poor chap of having killed his wife, and shut her
up there!"

"Did you?" said Delavoye, with an untimely touch of superiority. "That
never occurred to me."

"But you must have thought something was up?"

"I didn't think. I knew."

"Not what had happened?"

"More or less."

"I wish you'd tell me how!"

Uvo smiled darkly as he shook his head.

"It's no use telling certain people certain things. You shall see for
yourself with your own two eyes." He got up and crossed the room. "You
know what I'm up to at the British Museum; did I tell you they'd got a
fine old last-century plan of the original Estate? Well, for weeks I've
had a man in Holborn trying to get me a copy for love or money. He's
just succeeded. Here it is."

A massive hereditary desk, as mid-Victorian as all the Delavoye
possessions, stood before the open window that looked out into the
moonlight; on this desk was a reading gas-lamp, with a smelly rubber
tube, of the same maligned period; and there and thus was the plan
spread like a tablecloth, pinned down by ash-tray, inkpot, and the lamp
itself, and duly overhung by our two young heads. I carry it pretty
clearly still in my mind's eye. The Estate alone, or ra