, but he
returned this morning to burn his letters and change into civilian
clothes. Then he rushed away again in such a hurry that he forgot his
money. There is nothing more to be seen here. We had better make a few
inquiries of the housekeeper as we go downstairs."

They walked out, and Caldew locked the door behind him and placed the
key in his pocket. When they reached the entrance hall Colwyn paused
outside the door of the recess where the housekeeper lurked, like an
octopus in a pool. At Colwyn's knock a white face, topped by a white
cap, came into view through the narrow slit in the curtained glass half
of the door, and swam towards them in the interior gloom after the
manner of the head of a materialized ghost in a spirit medium's parlour.
The door opened, and the apparition appeared in the flesh, looking at
them with stony eyes. Caldew undertook the conversation:

"Did Captain Nepcote sleep here last night?" he curtly asked.

"I don't know."

"Well, has he been here this morning?"

"I don't know." The tone of the second reply was even more
expressionless than the first, if that were possible.

"It's your business to know," said Caldew angrily.

"It is not my business to discuss Captain Nepcote's private affairs with
strangers." The woman turned back into her room without another word,
closing the door behind her.

"D--n her!" muttered Caldew, in intense exasperation.

"These ancient females learn the wisdom of controlling their natural
garrulity when placed in charge of bachelors' flats," said Colwyn with a
laugh. "We will get nothing out of her if we stay here all day, so we
had better go."

"I am going straight back to Scotland Yard," Caldew announced with
sudden decision when they reached the pavement. "I must tell Merrington
all about this morning's work, and the sooner the better. We must have
the flat watched. Perhaps Nepcote may return."

"He will not return," said Colwyn. "He knows that we are after him, and
that the flat will be watched. But it is a good idea not to let him have
too long a start. Come, let us see if we can find a taxi, and I will
drop you at Scotland Yard."

They walked along to Sherryman Square, and esteemed themselves fortunate
in picking up a cruising taxi-cab with a driver sufficiently complaisant
to drive them in the direction they wished to go.

CHAPTER XXII

It was to Merrington's credit as an official that he suppressed his
feelings as a man on hearing