one night that he packed up and left the Mansion for good. He was assaulted by an invisible party from behind, and only escaped after a severe struggle. Whoever, or whatever, assaulted him disappeared in an instant, and he swore that he heard the closing of a door somewhere downstairs.

"Everything was done to keep the truth quiet, but of course it leaked out and the place has been regarded as haunted ever since. The servants left, save a few of the oldest, who live away from the Mansion under a separate roof, and have never seen anything unusual."

"That sounds very thrilling," I said; "but the affair may all be founded on nervous dread and hysteria."

"So I thought," said Oakes. "I went up there alone recently, however, and am glad to say that I got back alive."

"What! Did you see it?"

"No, gentlemen, I did not. There was nothing to see; but I learned enough to know that murder stalks there in the Mansion—that the mystery is a deep one, and my conduct nearly cost me my life.

"I have faced danger often, but I never faced an invisible violence, or had such a fight for my life as I had at the Mansion about three weeks ago."

Quintus Oakes was speaking earnestly, and we both were deeply interested. That the celebrated detective should have met such an experience placed the tale outside the realm of fiction. He was a calm man, used to facing danger, and not one to be easily deceived or frightened.

"Great Scott!" said Moore, "you must have had a fine time. Tell us about it. It must have been what the boys call a 'lalapazooza' of a time."

I had to smile at my friend, able and successful, and already a professional man of reputation, but ever fond of an occasional slang expression as a relief from the care with which he was usually burdened. He was well to do, but had been no idler, and knew the meaning of hard work.

"Yes," said Oakes, "I had a fine time."

At this moment the telephone on the desk rang, and Oakes reached forward and placed the receiver to his ear. After a few words of business he replaced it, but I felt a curious sensation of something missing, something unusual.

His hand had shot forward toward the hook and deposited the receiver thereon in one quick, instantaneous movement. The action had been so exact that the contact had given rise to no sound save the after-tinkle of the bell. Moore noticed it too, and looked at me, as much as to say: "How was that, for measuring distance?"

Then Oakes wheeled so as to face us again.

"Excuse me for the interruption. Now I will tell you my story in a few words."

CHAPTER III

Oakes's Experience

Oakes began:

"Mandel & Sturgeon gave me a letter to the chief care-taker, Cook, and I went to Mona as Clark, their agent, giving as an excuse for my presence there that Mr. Odell Mark contemplated making radical alterations in the Mansion before returning to it. Cook and his wife opened that portion of the Mansion which I thought best adapted for my temporary residence—about half of the place, I should say. I spent a few quiet days looking around the estate and the house. I was always on guard, however, lest I appear too inquisitive and thereby betray my true mission.

"There was an old maid-servant, Annie by name, and several gardeners about. These latter, I found, were never admitted to the Mansion. My meals were served in the dining-room, and this room was the one in which I spent most of my time. The servants gave me but little information regarding the mysterious doings that had so frightened their employers. I could tell by their action that they were genuinely afraid to be alone in the place, and they all cautioned me repeatedly. They seemed anxious that the affair should be investigated, and said that Mr. Odell should have had detectives at work on the mystery. It was evident they were afraid that they would lose their positions if no one returned to live at the Mansion soon.

"I noticed a strong under-current of contempt for Mr. Odell; they seemed to think he was a cowardly fellow, none too anxious to remain, or he would have investigated the affair. In fact, they behaved sometimes as though they thought that he might have been at the bottom of the mystery. Occasionally, Cook and his wife and Annie had stayed in the Mansion, cleaning up, and had never seen anything unusual. Nothing had occurred since Mr. Odell Mark had left—which certainly was peculiar.

"I could see that my true identity was not suspected. My presence seemed to have inspired confidence in them all. I called Cook and his wife, or Annie, into my rooms for a talk quite frequently. Nothing happened, and I began to feel that there was exaggeration somewhere; but, nevertheless, I moved with caution and slept in the back room over the dining-room with the doors carefully locked. I insisted that Mr. and Mrs. Cook sleep in the front room. The servants at first demurred, but finally consented when I told them that if they did not do so I would not remain, and would report unfavorably as regards the remodeling of the Mansion. I noticed that they bolted their doors carefully every night and kept a light burning in their room. This I knew, as its rays shone through under their door into the hall.

"This satisfied me that they were on guard and afraid, and consequently unaware of the real nature of the mystery.

"Late one night, after about a week, I was looking out of one of the windows in the dining-room, watching a boat passing. The lights upon her and the throbbing of her engines, half a mile away, were plunging me into a reverie, when suddenly I felt a peculiar sensation of uneasiness. I glanced along the porch, and at the windows; everything seemed all right. I turned, and saw Annie some distance up the hall attending to a lamp at the foot of the stairs. The afternoon paper lay on the table. I walked over to it and picked it up, stationing myself a few feet away from the hall door, where I commanded a view of the entire room, the windows and the balcony. I heard, or fancied I heard, a step or shuffle, and then instantly something closed around my throat and I was pulled backward and downward. I heard a rush in the hall and saw Annie's terrified face looking into the room, but she did not see me. I tried to cry out for help, but was unable to raise my voice. Realizing that I was being killed without aid, I struggled with all my power. I have an indistinct recollection of a shriek in the hall, then a rustling sound, as of garments, near me. The next I knew, Annie, Cook and his wife, with two gardeners, were working over me. One of the gardeners had opened my shirt and thrown water upon my throat. I was unconscious for some minutes, they said; but when I recovered my senses I ordered all hands to keep their mouths closed, under pain of instant dismissal. Inquiries instituted by me revealed that Annie had first heard my struggles, and the shriek that had been given was hers. Response had been quick, but when Cook first entered the room, backed up by the wife and old Annie, I was lying limp and unconscious, face downward on the floor, as though I had been thrown violently forward."

The recital of this narrative had been given in a quiet, dignified manner—one of absolute conviction. It was an impartial statement of fact, and we were profoundly impressed.

Dr. Moore turned to me and said: "Well, do you feel like joining us?"

"Ah! Then you are in this too?" I exclaimed.