"Ida placed it there."

It was enough. The entire facts of this mysterious case were clear to me. I required nothing more to prove Edward Layton's innocence than the possession of the document written almost in her death-throes by his unhappy wife.

I unlocked the door and called up Fowler. Briefly and swiftly I told him what was necessary, and said it was not at all improbable that this document was in Ida White's lodgings at Brixton; and I had scarcely uttered the words before a rat-tat-tat came at the street door.

"It is she!" cried Eustace.

"Who?" I asked, in great excitement.

"Ida," he replied.

"It serves our turn exactly, sir," muttered Fowler to me, and then addressing Eustace, he said, "Is that your bedroom?" pointing to a communicating door.

"We will go in there. Let the lady come up."

We disappeared, leaving the communicating door partially open, and the next minute I heard Ida White's voice.

"Cursed luck!" she cried. "I've lost eighty-five pounds to-day. I tell you what it is, Eustace--if we can't wheedle your old governor into forgiving us after we are married, we shall have to turn book-makers ourselves. You shall take the bets, and I will do the clerking. It will be a novelty, and we shall make pots of money."