The boy had gone after another customer, and Oakes continued: "Martin is my aide; he has posted me. Good-by! See you later. Explain some other time."

We parted, and I went about my preparations for departure with that exhilaration that men feel when about to enter into some strange undertaking. It was to be a novel experience for me, and I frankly confess that certain misgivings haunted me. That I was entering, willingly, to be sure, upon a journey of many possibilities I did not for one moment doubt; that I should need the weapon already purchased, and the utmost coolness that I could muster, seemed to me more than likely. At this date I felt nothing akin to fear, and the knowledge that Quintus Oakes was to be our leader prevented a too serious estimate of the possible consequences.

Later on I did feel some regrets at having hurled myself into the episodes that followed, but this feeling vanished soon in the excitement of the events that transpired at Mona.

Shortly before the appointed time I arrived at the station and strolled about the rotunda in search of Oakes.

I espied him at the paper stand, dressed in a dark heavy overcoat and a hat like mine. His recognition of me was instantaneous, but he made no movement until, after buying a paper, he walked past me to the door.

Looking at me with a glance that warned me, he stepped out and into a car that was approaching. I jumped on the same car, and in a very few moments he and I were going up the Sixth Avenue Elevated stairway, but acting as strangers to one another.

There were many persons boarding the Harlem train with us. It was a tiresome ride to the terminus, but when Oakes and I stepped out and down to the street, he jumped into a carriage in waiting, drawn by a pair of horses, and beckoned to me. I stepped in also, and sat by his side on the back seat.

The driver started at a quick pace across the bridge and into Jerome Avenue.

Oakes turned to me: "It seems that my movements are watched by men in a rival agency. I have detected no followers, but time will tell if they exist. I saw a fellow watching me at the station, and we may have easily been followed on the elevated train; in such a crowd one cannot detect."

"Why do they watch you, Mr. Oakes? Are they suspicious that we are going to Mona?"

"No, not at all," answered Oakes. "They are watching to see _where_ I am going. You see," he continued, "I am working on several other cases, and perhaps they are, too. You realize there are times when men of my profession cross each other's paths, and it is advantageous to know what the other fellow is doing."

"I see. Keeping tab on one another!" I said. "Rather expensive work, is it not?"

Oakes smiled. "Yes, but it is business. I like to know when a rival leaves town. I keep a pretty close watch myself on some of them."

We drove rapidly, and soon pulled up at an out-of-the-way roadhouse.

"Come," said Oakes, alighting.

A portly German was behind the bar, evidently the proprietor.

Oakes made a sudden movement of his hand, and the door was locked. We two were then shown into a rear room where two other men were seated--both tall, well-built fellows, and both dressed as we were, in dark overcoats and black Fedora hats.

They saluted Oakes, and after a word or two stepped into the bar-room, where the German served them with drinks. In a minute they were in our carriage and driving away toward Yonkers.

"I see now why you were particular as to my dress."

"Yes, a subst.i.tution like this is useful sometimes. I thought I might be forced to make one. Much better than nonsensical disguises. We will soon know if any one is coming after us," he continued. "This is really the last place before the fork of the road, and anyone following us would have to be in sight all the time, or else stop here for information."

The proprietor motioned us upstairs to a front room, and Oakes said to him: "Remember, we have gone to Yonkers." But the good-natured German evidently knew his business, for he only smiled and went off muttering something to himself about a "d.a.m.ned good mix-up."

In a few minutes two men drew up in a buggy, and were admitted below by the obsequious old fellow.

Then we heard the question: "Have you seen two tall gentlemen in black coats and soft hats hereabouts, Dutchy?"

The German thought a moment: "Yah, yah; dare vas two big fellers just here; dey vas took some viskey and got away quick."

"Which way?" asked the men.

"Dey vas gone up dar Yonkers Road."

Oakes chuckled. "The old fellow is all right; an old friend of mine."

Then we heard the men say: "Here, Dutchy, here's something for you," and we knew they had given him a tip.

In a moment they were gone, and the old fellow was to be heard chuckling audibly to himself: "Five dollar for von great big mix-up."

Oakes watched the team turn up the Yonkers Road after our decoy, and then he said:

"Come, Stone, move quickly." He led the way downstairs to the back entrance, and to the stable, where we found a man with a team. He saluted us. It was the carriage in which Oakes's men had come out.

"Drive hard for the Harlem Station; we can catch the 10:30 train," was the order.

Our driver evidently knew what to do, and we soon pa.s.sed out of the carriage-way.

At the side of the door we halted a moment, and I saw Oakes give the German a twenty-dollar bill.

"Remember," he said, "not a word."

We caught our train after a long drive to the east, and back over the Harlem River. When we seated ourselves in the sleeper, Oakes turned to me quietly. "Please remember, Stone, that you are a possible buyer, and that I am Charles Clark, agent for the owner of the Mark Mansion. We have had a pleasant evening together so far, have we not?"

He smiled in his quiet, unruffled manner as he spoke.

"Yes--rather active," I said. "I presume those other fellows are thinking so too, probably."

"Only the last two," said Oakes; "my men are home by this time."

Shortly after midnight we arrived at the station at the foot of the hill which hid the beautiful town of Mona.

"Keep your senses alert," said Oakes as we left the train, "for we are now in the region of uncertainty. We had better not walk to the hotel, although it is only about a mile. The hour is too late."

The solitary hackman, seeing us approach, roused himself from his sleepy lethargy and soon we were slowly ascending the hill. The well-kept road was lighted here and there by electricity, an agreeable witness to the civilization around us.

I saw Oakes place his weapon in his outside overcoat pocket--as he said, the most convenient place for it to rest, clad as we were.

The action was a vivid reminder of the experiences of his last visit, and of the caution of the man.

Without further adventure of any kind we arrived at the little hotel, with its sleepy night clerk and its gloomy office. This opened right on the sidewalk by means of a large wooden door, hung a low step above the pavement, and fitting so poorly in its frame that the rays of the light from within sought exit beneath it.

_CHAPTER V_

_The Letter_

While Oakes and I were in the first stages of our journey, Dr. Moore stood in his back office at the close of business hours, wondering if the adventure that Oakes had so well described to us could in any way have been originated by other than physical forces. Moore was a deep student of mental phenomena. He had on more than one occasion heard histories of terrible tragedies, so real in their wording that the picture conveyed was the practical guarantee of their origin at human hands; but, nevertheless, these histories had been proved to be but the imaginings of a diseased mind--products of a delusion.