As a matter of fact, he probably thought, as I did, that this was a
familiar case of a man of possibly blameless life who had become
subject to that delusion which leads people to believe themselves
threatened by mysterious and unnameable danger.

Our visitor inhaled deeply.

"You, of course, are waiting for the facts," he presently resumed,
speaking with a slowness which told of a mind labouring for the right
mode of expression. "These are so scanty, I fear, of so, shall I say,
phantom a kind, that even when they are in your possession you will
consider me to be merely the victim of a delusion. In the first place,
then, I have reason to believe that someone followed me from my home to
your office."

"Indeed," said Paul Harley, sympathetically, for this I perceived was
exactly what he had anticipated, and merely tended to confirm his
suspicion. "Some member of your household?"

"Certainly not."

"Did you actually see this follower?"

"My dear sir," cried Colonel Menendez, excitement emphasizing his
accent, "if I had seen him, so much would have been made clear, so
much! I have never seen him, but I have heard him and felt him--felt
his presence, I mean."

"In what way?" asked Harley, leaning back in his chair and studying the
fierce face.