There certainly had been lively work, for within six hours after the discovery of the destroyed aeroplane, a message had been sent from New York to Garden City, Long Island, a machine despatched from that point to the little town among the Alleghanies in eastern Pennsylvania, and an aerial ship had sailed across the State of New Jersey to the destination more than two hundred miles from its starting point. When and by what means the merchant had learned of the straits of his son could not as yet be guessed, but the news must have been waiting when he reached his office in the city, since young Mitchell said it was received at the factory between eight and nine o’clock that morning. The flight to Groveton was made in about four hours, with a brief halt on the way to replenish the supply of gasoline. Traveling at the rate of fifty miles an hour and sometimes faster was surely “going some.”

As Mitchell afterward explained, he had visited the section twice, and was familiar with it. He lost no time, therefore, in groping, but recognized rivers, cities, towns, and the general conformation of the country over which he glided, and identified Groveton long before any one there dreamed he intended to make a call.

Harvey glanced at the little watch on his wrist, and noted the exact time of starting. Eleven minutes later to the second, he volplaned into the open space in front of the hotel. Although the distance passed was less than by rail, he must have averaged nearly if not quite a mile a minute.

The lesson of the “accident” to the other machine was not lost upon the two young men. It was hardly to be supposed that any one would try to harm the new one, but Bohunkus was ordered to stay with it and see that all hands were kept off.

“Yo’ bet I will,” he replied, fully alive to his duty; “de fust chap dat lays an onkind hand on dis pet will git broke in ’leben pieces and den flung ober de fence.”

Several idlers were gaping at the fractured aeroplane huddled in the wagon sheds of the hotel. Mitchell quickly finished his examination.

“The man or men who did that,” he said in a low voice to Harvey, “showed the devil’s own spite. It looks as if the scoundrel was crazy.”

Harvey glanced at his companion. Did he suspect the truth? His looks and manner, however, showed that he was not thinking of Professor Morgan. The remark was a natural one, under the circumstances. Harvey was not disposed to reveal anything, since he saw no good to be accomplished thereby, while an unpleasant situation might develop.

“You can save something out of the wreck?” remarked the owner inquiringly.

“Considerable; I shall ship what’s worth while to the factory at Garden City, and in a few weeks you will have a new machine as good as ever.”

“The greater part of it will have to be new,” commented Harvey.

“That being so, you can return this one in exchange, if you wish.”

“Is there any way, Mitchell, in which I can serve you?”

“None; I shall have what is left of the machine gathered up, as I said, and sent to the factory; that will take the remainder of the day, when I shall follow in the train. Meanwhile you are not called upon to lose any part of your vacation. There is no perceptible difference between the two biplanes, so you don’t need any help from me.”

The youths walked back to where a small group remained staring at the biplane in which Bohunkus Johnson was still seated, as alert as a watch dog. As the couple approached, the negro crooked his stubby forefinger to his friend, who went forward.

“What is it, Bunk?”

“Yo’s forgot something.”

“What is that?”

“It’s ’bout dinner time.”

The colored youth meant to whisper, but his husky aspiration carried as far as if he had spoken in a loud tone.

“He is right,” remarked Mitchell; “let us have dinner together.”

The old fellow who served the hotel as hostler was hired to stay by the machine and to keep every other person at a distance, while the three went in to their meal.

During these minutes, Harvey was on the watch for a sight of Detective Pendar. He much wanted to have a few words with him, but was puzzled how to bring it about. Harvey had given up his room, so he could not signal to the officer to follow him thither and there was no understanding as to how they should otherwise meet.

Pendar, however, remained invisible until Bohunkus had perched himself in the seat in front of the tank, and Harvey had his hands on the levers. Mitchell stepped to the rear to give a swing to the propeller blades. The machine was pointed to the left, where the highway showed quite a sharp slope downward, of which the young aviator meant to take advantage.

At this crisis, when twenty pairs of eyes were upon the party, Harvey heard an odd sounding cough. He looked around and saw a man standing on the porch above the other spectators. It was Detective Pendar, who was looking keenly at Harvey. As their eyes met the former rubbed his smooth chin thoughtfully and winked once, but made no other sign that he recognized the youth.

“Now what does he mean by that?” Harvey asked himself; “a wink may signify one of a score of things.” As the only reply he could make, he winked in return. A dozen of the group might have accepted it as meant for him, but, if so, he must have been equally puzzled with the author of the signal, who a minute later was scooting through the air and steadily rising.

Harvey had decided to carry out so far as he could the programme agreed upon the day before by him and Pendar. The only change was that caused by the enforced delay. Instead of making his search in the forenoon, it now would have to be done in the afternoon. He shot upward, until barely five hundred feet above the earth, and then headed westward over the long stretch of forest of which mention has been made. It was advisable that he should keep as near the ground as practical, since his view would thereby be improved.

Bohunkus Johnson was still in the dark on two points: he had no conception of the serious business upon which his companion was engaged, knowing nothing of the kidnapped child, and, though certain in his own mind that Professor Morgan was the man who had wrecked the aeroplane, he had never suspected that he was insane. Ignorance on the former point was a good thing, but as regards the latter it proved a serious mistake, as has been intimated in another place.

It need not be said that a heavier-than-air machine must progress rapidly in order to sustain itself aloft. When such motion stops, through breakage, accident or the will of the aviator, an aeroplane obeys the law of gravity and comes to the ground. It does not fall, as is the case with a balloon.

It would never do to withdraw care from the machine, which worked with perfect smoothness, but having headed westward and struck as moderate a gait as was practical, Harvey Hamilton gave all the attention possible to the country under his feet. He noted the wide expanse of forest in its exuberant foliage, a flashing stream of water and the foam of a tumbling cascade on the slope of the farther ridge. In the other direction wound the railway line over which he and Bunk had ridden earlier in the day. The sky was clear and sunshiny with a rift of fleecy clouds in advance, but at so great an elevation that no inconvenience was to be feared from them. The town of Groveton was so distinctly seen that he recognized several of the buildings, including the hotel, which he had observed on his brief visit. Far away in the radiant horizon the steeples and tall buildings of a city showed, but it was all strange to him. He could identify nothing beyond that which has been named.

Harvey had sailed probably three or four miles from Chesterton when he was thrilled by a sight that roused instant hope. In the midst of the wood, an open space several acres in extent was crossed by a stream of considerable size, on its winding way to the distant Delaware. In the center of this clearing stood a log cabin, which recalled that of Abisha Wharton where Harvey and Bunk had spent a night after leaving home on their outing. The land showed slight signs of cultivation, but from the stone chimney running up the outside of the decayed structure, he traced a faint blue spiral of smoke.

“That shows somebody lives there,” was Harvey’s thought; “from what Pendar told me I believe it’s the very place where the kidnappers are holding the child a prisoner.”

He leaned far over and scrutinized the picture as he swept over it. What he longed to see was the little girl running about or playing in front of the cabin, or one or more of her captors. It would seem that the loud throbbing of his motor ought to have attracted the attention of the occupants, but it did not do so, and the spot speedily glided from sight. When Harvey twisted his neck, however, in the effort to see more, he noticed that Bunk had also turned and was attentively studying the picture. Conversation in such circumstances was impossible, but Harvey hoped his companion had discovered something—a supposition which he was certain to remember when the time came for a halt in their flight.

Had our young friend followed his inclination, he would have circled around and returned over the cabin, in order to inspect it further, but that most likely would have roused the suspicion of the abductors, and the moment they believed an aeroplane had been impressed into the service against them, that moment the usefulness of the contrivance would be ended. He could remember the location clearly, and would give the detective all the directions he needed.

“I didn’t see any wagon road or trails, but there must be one path at least which connects the house with the outer world. Those men have a source of supplies and they can’t help leaving footprints.”

As Harvey reasoned out the problem, the solution was simplified. Simmons Pendar was confident that the hiding place was somewhere in the stretch of wilderness, but to search for it would prove fatal. The effort was certain of discovery by the watchful guards. Now, however, since the exact location of the cabin seemed to have been found, a speedy approach ought to be within the detective’s power. The near future must answer the question.