along the corridor,
and disappeared into Franklin Fullaway's suite. It was all over in less
than a minute, and Allerdyke turned into his own door, smiling
cynically to himself.

"She looked right and left, but she forgot to look up!" he muttered.
"Ah! those small details. And what does that mean? Anyway, I know which
door she came out of!"

He glanced at his watch--precisely half-past eleven. He made a note of
the time in his pocket-book and went to bed. And next morning, rising
early, as was his custom, he descended to the ground floor by means of
the stairs instead of the lift, and as he passed the door from which he
had seen Mrs. Marlow emerge he mentally registered the number.
Fifty-three. Number fifty-three.

Allerdyke, who could not exist without fresh air and exercise, went for a
stroll before breakfast when he was in London--he usually chose the
Embankment, as being the nearest convenient open space, and thither he
now repaired, thinking things over. There were many new features of this
affair to think about, but the one of the previous night now occupied his
thoughts to the exclusion of the others. What was this woman doing,
coming--with evident secrecy--out of one set of rooms, and entering
another at that late hour? He wanted to know--he must find out--and he
would find out with ease,--and indirectly, from Fullaway.

Fullaway always took his breakfast at a certain table in a certain corner
of the coffee-room at the hotel; there Allerdyke had sometimes joined
him. He found the American there, steadily eating, when he returned from
his walk, and he dropped into a chair at his side with a casual remark
about the fine morning.

"Didn't set eyes on you last night at all," he went on, as he picked up
his napkin. "Off somewhere, eh?"

"Spent the evening out," answered Fullaway. "Not often I do, but I
did--for once in a way. Van Koon and I (you don't know Van Koon, do
you?--he's a fellow countryman of mine, stopping here for the summer,
and a very clever man) we dined at the Carlton, and then went to the
Haymarket Theatre. I was going to ask you to join us, Allerdyke, but you
were out and hadn't come in by the time we had to go."

"Thank you--no, I didn't get in until seven o'clock or so," answered
Allerdyke. "So I'd a quiet evening."

"No news, I suppose?" asked Fullaway, going vigorously forward with his
breakfast. "Heard nothing from the police authorities?"

"Nothing," replied Allerdyke. "I suppose th