He was indeed an inveterate pipe-smoker, and only rarely did he truly enjoy a cigar, however choice its pedigree. With a sigh of content he began to fill his briar. His mood was more restful, and covertly I watched him studying our host. The night remained very warm and one of the two windows of the dining room, which was the most homely apartment in Cray’s Folly, was wide open, offering a prospect of sweeping velvet lawns touched by the magic of the moonlight.

A short silence fell, to be broken by the Colonel.

“Gentlemen,” he said, “I trust you do not regret your fishing excursion?”

“I could cheerfully pass the rest of my days in such ideal surroundings,” replied Paul Harley.

I nodded in agreement.

“But,” continued my friend, speaking very deliberately, “I have to remember that I am here upon business, and that my professional reputation is perhaps at stake.”

He stared very hard at Colonel Menendez.

“I have spoken with your butler, known as Pedro, and with some of the other servants, and have learned all that there is to be learned about the person unknown who gained admittance to the house a month ago, and concerning the wing of a bat, found attached to the door more recently.”

“And to what conclusion have you come?” asked Colonel Menendez, eagerly.

He bent forward, resting his elbows upon his knees, a pose which he frequently adopted. He was smoking a cigar, but his total absorption in the topic under discussion was revealed by the fact that from a pocket in his dinner jacket he had taken out a portion of tobacco, had laid it in a slip of rice paper, and was busily rolling one of his eternal cigarettes.