Harvey Hamilton stood speechless. When he spoke to Professor Morgan, they were no more than a rod apart, with only the broad open space in front of the hotel between them. Upon hearing himself addressed, the man had looked straight into the face of the lad and then, as already said, passed on without the faintest sign of recognition.

A more direct snub cannot be imagined, and yet it was not in the nature of a snub. Nothing had occurred that could justify so marked a slight. The humiliation which Harvey felt for a few seconds quickly passed away.

“He must have been too absorbed in reverie to see me, and yet that can’t be possible, for he showed that he heard me call him by his title.”

By and by the young aviator reached the only conclusion that seemed reasonable.

“He is a crank in every sense of the word; he is as crazy as a June bug; he was friendly enough last night and this forenoon, and now he is in a different mood. Well, I shall always feel grateful for the good turn he did me. If we meet again, he may be in a more genial frame of mind; at least I hope so.”

The downpour was increasing and the air had become so chilly that Harvey passed inside to the sitting-room. The same number of men were present as before, smoking, chewing and gossiping. He glanced into their countenances, as he moved his chair beside the sleeping Bohunkus Johnson, prepared to pass the dismal hours as best he could without finding any reading matter in the form of books or newspapers. He had registered before dinner and engaged a room for himself and another for his companion. His letters were given to the landlord, who promised to send them to the post office in time for the afternoon’s mail.

Somehow or other, there was one man among the group in whom Harvey felt a slight interest, though he attributed the fact to the lack of anything else to engage his mind. This individual was standing at the desk, when Harvey came from the outside, studying the dog-eared register, as if he too was guided by some idle impulse. He glanced at the newcomer and followed him into the larger room, where he lighted a cigar and took a seat against the other wall.

He was of slight frame, in middle life, dressed in a gray business suit, with clean shaven face, a thin sharp nose, good teeth and keen blue eyes. He was alert of manner, and might well have been a drummer held in town for a brief while against his will. When Harvey glanced at him again he quickly averted his eyes. Apparently he did not wish to be detected in the act and he came within a hair of succeeding in his attempt. He gazed in an absent way through the door leading to the bar-room and smoked his cigar like a man who thoroughly enjoyed the weed.

Being in an idle mood, Harvey twisted the corner of his handkerchief into a tight spiral, making the end quite stiff and pointed, and, leaning forward, began drawing it back and forth against the base of the sleeping Bohunkus Johnson’s nose. Immediately every other person in the room began watching the proceedings.

For a little while the negro slept on undisturbed. Then he suddenly crinkled his broad, flat nose and flipped his hand at the fly or mosquito that was supposed to be tickling him. The spectators grinned, and Harvey waited till Bunk was slumbering as heavily as before. Then he resumed his role of Tantalus. This time he tickled so energetically that Bunk struck impatiently at his tormentor and banged the top of the chair a vigorous blow—so vigorous indeed that several of the men snickered and the dusky youth opened his eyes and raised his head, as wide awake as ever in his life.

“Think yo’s smart, doan’ yo’?” he growled, donning the cap that had fallen to the floor and shaking himself together.

“The next thing, Bunk, you’ll fall asleep in the biplane and tumble out head first.”

“I doan’ see dat it’ll make any difference to yo’ if I do,” replied the other, nettled by the general laughter more than by the manner of his awaking.

“It won’t, but it will to you. If you want to sleep all the time go to your room.”

Bohunkus mumbled something, shifted his position, sank down in his chair until he seemed to be sitting on the upper part of his spine, and in a few minutes was nodding again. Harvey molested him no further, but looking up discovered by a furtive glance that the thin young man in gray had been studying him for an indefinite time, though quick to shift his gaze as before.

Harvey drew his note-book from his pocket, and, bringing his chair to the table, began making sketches with his pencil, wholly from imagination. The stranger, a little while later, drew up his seat opposite and busied himself in the same way. Thus the situation remained for perhaps ten minutes.

Suddenly a pellet of paper the size of a dime was flipped across the brief space and fell upon the page that was covered with Harvey’s tracings. He knew it came from the man on the other side of the table, and he understood it was meant to be secret. It was an extraordinary way by which to communicate with him, when it would have been easy to speak one or two words in so guarded tones that they could not be overheard. But the man must have had his reasons, which would appear later.

With that quickness of resource that has been shown to be a marked trait of Harvey Hamilton, he did a bright thing. Without betraying any haste or interest, he picked up the tiny wad and slipped it into his waistcoat pocket. He did not even look at the stranger, but nodded his head, keeping his eyes on his note-book. A minute later the man rose from his chair and sauntered into the bar-room, turning off to one side so as to be out of sight of the youth had he looked for him while still in his seat, which he did not.

It was with curious emotions that Harvey saw he was called upon to play a peculiar role. He had been given a written communication in such a manner as to make it certain the sender wished no other person to know what had taken place. The youth must read the message, but do so secretly. To untwist the bit and examine it while in the sitting-room would betray everything. Only one course remained.

It was not yet dark, for it will be remembered it was summer time, but stepping to the bar, behind which the landlord was standing serving a customer, Harvey asked for the key to his room. It was handed to him from a nail and he was directed to ascend the stairs to the upper hall, along which he was to walk until he saw the number “34” on the door.

As Harvey started to follow directions, he glanced about the bar-room, in which there were six or eight persons, but the author of the mysterious message was not among them. He was standing on the porch outside, and looked for an instant through the window at Harvey, but no sign or signal was exchanged between them.

Not until he had entered his room and locked the door did Harvey unroll the paper pellet, and, standing by the window where the light was good, read the following words:

“I shall knock at your door at nine o’clock this evening. Keep your colored servant out of the way. I have something important to say to you. When we meet outside of your room neither must show that he has ever met the other. Don’t fail me.

After the perplexity caused by these curious sentences, Harvey Hamilton’s feeling was that of amusement.

“I have come to Chesterton in my aeroplane, and dived head first into one of the most tremendous mysteries that ever was. Bunk and I set out to find adventure and it looks as if we had struck it rich. But what the mischief can it all mean?”

Try as hard as he might, he could not take the matter as seriously as it seemed to him he ought to do. The time was well on in the twentieth century, he was in one of the most civilized sections of the Union, and things as a rule were conducted in accordance with law. Surely “S. P.” was not hinting at murder, or burglary, or incendiarism, or any other heinous crime.

“What is he driving at and who is he?”

Harvey Hamilton would not have been a bright, high-spirited youth of seventeen years had he not been stirred by the curious communication that had been delivered so oddly to him. He speculated and theorized, and the more he did so the more he was puzzled.

“Some folks like to be mysterious,” he said, “and the less cause they have for being so the more secret they are. Why didn’t ‘S. P.’, whoever he is, drop me a word, which he could have done without it being noticed by any one else?

“It must have been there was another person in the room that he was afraid would become suspicious, but I have no idea who he was. It is odd that this fellow is the only one who interested me.

“What can his business be with me? I was never in this part of the world before and haven’t had anything to do with the people here, nor anywhere in the neighborhood, except those young men this forenoon. It can’t have any relation to them, for they have not had time to reach Chesterton since our run-in.”

“How about Professor Morgan?” Harvey asked himself with a start. “I know he is in town and didn’t show any pleasure when I recognized him. Can it be that he and ‘S. P.’ have anything between them in which I am concerned?”

He sat for a long time turning over the perplexing subject in his mind, with the only result of becoming more befogged.

“Pshaw! what’s the use?” he exclaimed impatiently, as he came to his feet and donned his cap; “it is nearly night and I have to wait but a few hours, when he will make everything clear. So here goes.”

He locked his door behind him and started down the long hall. At the head of the stairs, whom should he meet but the alert looking man in gray? Harvey was about to suggest that they return to his room together and have their conference, but the other did not seem to see him; and recalling the warning, the youth passed down the steps as if he had encountered an utter stranger. The latter did not show up at the supper table and Harvey was relieved, for it would have been some embarrassment to him. It may have been the man’s knowledge of this fact that caused him to keep out of the way.

Time passed slowly. When Harvey looked at his watch and saw that it lacked fifteen minutes of the time appointed, he started for his room. Bohunkus had already gone up stairs. When he bade his friend good night, he said to him:

“I need sleep, Bunk, so stay in your room till I call you in the morning.”

“All right; I hain’t no ’bjection; I sha’n’t get up till yo’ bang on my door.”