"An impression," he replied; "but it has gone now."

"I understand," I said, quietly.

Familiarity with crime in many guises and under many skies had
developed in Paul Harley a sort of sixth sense. It was a fugitive,
fickle thing, as are all the powers which belong to the realm of genius
or inspiration. Often enough it failed him entirely, he had assured me,
that odd, sudden chill as of an abrupt lowering of the temperature,
which, I understood, often advised him of the nearness of enmity
actively malignant.

Now, standing at the window, looking down into that old-world garden,
he was "sensing" the atmosphere keenly, seeking for the note of danger.
It was sheer intuition, perhaps, but whilst he could never rely upon
its answering his summons, once active it never misled him.

"You think some real menace overhangs Colonel Menendez?"

"I am sure of it." He stared into my face. "There is something very,
very strange about this bat wing business."

"Do you still incline to the idea that he has been followed to
England?"

Paul Harley reflected for a moment, then:

"That explanation would be almost too simple," he said. "There is
something bizarre, something unclean--I had almost said unholy--at work
in this house, Knox."