esents in connection with the cotillon promoted by the Marquis.

At two o'clock the following morning the Marquis was entertaining a
select party in the smoking-room. The ladies had all vanished by this
time. The Marquis was speaking of his adventures. He really had quite a
talent in that direction. Naturally, a man of his wealth was certain to
be the mark for swindlers. Merrick listened with an approving smile. He
knew that most of these stories were true, for they had all been
recorded from time to time at Scotland Yard.

"You would have made an excellent detective, Marquis," he said. "You
have made it quite clear where the police blundered over that Glasgow
tragedy. I suppose you read all about the Grand Coast Railway murder."

The Marquis started ever so slightly. There was a questioning look in
his eyes.

"Did you?" he said. "Naturally one would, Colonel. But a matter the most
inexplicable. I gave him up. From the very first I gave him up. If the
guard Catesby was not the guilty person, then I admit I have no theory."

One by one, the smoking-room company faded away. Presently only Merrick
and the Marquis remained, save one guest who had fallen asleep in his
chair. A sleepy waiter looked in and vanished again. The hotel was
absolutely quiet now. Merrick, however, was wide awake enough; so,
apparently, was the Marquis. All the same, he yawned ostentatiously.

"Let us to bed," he said. "To-morrow, perhaps----"

"No," Merrick said somewhat curtly. "I prefer to-night. Sit down."

The last two words came crisply and with a ring of command in them. The
Marquis bowed as he dropped into a chair and lighted a fresh cigarette.
A little red spot glowed on either of his brown cheeks, his eyes
glittered.

"You want to speak to me, Colonel?" he said.

"Very much indeed. Now, you are an exceedingly clever man, Marquis, and
you may be able to help me. It happens that I am deeply interested in
the Grand Coast Express murder; in fact, I have devoted the last two
months to its solution."

"With no success whatever, my dear Colonel?" the Marquis murmured.

"On the contrary, my dear Marquis, with absolute satisfaction. I am
quite sure that you will be interested in my story."

The Marquis raised his cigarette graciously.

"You are very good to give me your confidence," he said. "Pray proceed."

"Thank you. I will not bore you with any preliminary details, for they
are too recent to have faded from your memory. Sufficien