brary of
Rowchester on the evening of the eighteenth of this month."

"That is so, sir," I answered. "And early the next morning I reported
to the Duke that the papers had been tampered with."

There was a dead silence for several moments. Lord Chelsford glanced at
the Duke, who sat there imperturbable, with a chill, mirthless smile at
the corner of his lips. Then he looked again at me, as though he had
not heard aright.

"Will you kindly repeat that, Mr. Ducaine?" he said.

"Certainly, sir," I answered. "I had occasion to go to the safe again
early on the morning of the nineteenth, and I saw at once that the
documents in question had been tampered with. I reported the matter at
once to his Grace."

The eyes of every one were bent upon the Duke. He nodded his head
slowly.

"Mr. Ducaine," he said, "certainly came to me and made the statement
which he has just repeated. I considered the matter, and I came to the
conclusion that he was mistaken. I was sure of it then. I am equally
sure of it now."

"Tell us, Mr. Ducaine," Lord Chelsford said, "what your reasons were
for making such a statement."

I took a piece of red tape and a newspaper from the table before which I
stood. I folded up the newspaper and tied the tape around it.

"When I put those documents away," I said, "I tied them up with a knot
like this, of my own invention, which I have never seen used by anybody
else. In the morning I found that my knot had been untied, and that the
tape around the papers had been re-tied in an ordinary bow."

"Will you permit me for a moment," the Duke interposed. "The safe, I
believe, Mr. Ducaine, was secured with a code lock, the word of which
was known to-whom?"

"Yourself, sir, Colonel Ray, and myself."

The Duke nodded.

"If I remember rightly," he said, "the code word was never mentioned,
but was written on a piece of paper, glanced at by each of us in turn,
and immediately destroyed."

"That is quite true, sir."

"Now, do you believe, Mr. Ducaine," the Duke continued, "that it was
possible for any one else except us the to have attained to the
knowledge of that word."

"I do not sir," I admitted.

"Do you believe that it was possible for any one to have opened the safe
without the knowledge of that word?"

"Without breaking it open, no, sir."

"There were no signs of the lock having been tampered with when you went
to it in the morning?" "None, sir."

"It was set at the correct word, the word kno