"And you certainly made a mighty good guess," declared Don.
"Yes; so it seems," replied Monsieur de Morancourt, with a smile. "I spent a great part of my time in the château searching for an entrance to the subterranean passageway. On the occasion of your first appearance I must have entered the building very soon after you. It was I who stumbled over the chair, and, naturally, I realized at once that it had been moved. Surmising the presence of some one, I merely waited until I heard you coming down-stairs and then walked outside.
"After your departure, I reëntered, and, wishing to see if anything had been disturbed, made a hasty examination—that explains the flashing light at the window."
"How very simple mysteries sometimes appear after one has learned all about them," laughed Don. "And maybe we wouldn't have been surprised at the Cheval Noir if we'd known that you were the very man responsible!"
"Well, rather!" chuckled Chase.
"And we never even had a suspicion of the truth," laughed Dunstan.
"I certainly was astonished to run into the mysterious visitors," declared Monsieur de Morancourt. And then addressing Chase, he added: "When you made your early morning call my presence is explained by the fact that I had spent the night in one of the upper rooms.
"Now, Messieurs, I believe there is nothing further to add to my story."
The ambulanciers all declared that it had been a very interesting one.
At length, in the midst of a general conversation and much levity and noise, Bodkins, holding his banjo aloft, shouted: