HARVEY asked in a muffled voice: “May I take away my handkerchief?”  
“It can do no harm, but I don’t know that your precaution did any good.”
 
“I kept my eyes open and peeped over the top; the way the Professor studied us proved he had misgivings, but he did not see my features.”
 
“It looks as if he is not satisfied.”
 
The elder referred to the fact that the aviator, instead of veering to the left and coming to a stop as he had done earlier in the day, continued his straightaway course. Harvey unshipped his field glass and leveled it at the object which rapidly grew smaller and finally flickered from sight.
 
“He is doing that to mislead us,” said Harvey.
 
“Is there any way by which we can make him believe he has succeeded?”
 
“How would it do to stop paddling and begin fishing if he comes into sight again?”
 
“I am proud of a brother bright enough to think of that; it is a good plan, for if he is not satisfied[147] he will come back for another view and he mustn’t catch us napping.”
 
Accordingly the paddle was swung again, and the younger brother gave his attention to watching the sky in every direction, for it was possible that with so swift a machine as was at his command the Professor might make a wide circuit and swoop down upon them again from the rear.
 
“If he does,” said Harvey, “it will show that he doesn’t like the look of things, and if I resort to my handkerchief again he will know why I do so.”
 
“Which will be as bad as if you didn’t do it. If we can reach the end of the lake before he returns we’ll begin our hunt without more delay, but—”
 
“By George! Yonder he comes!”
 
“Quick! Get out your fishing line; I always carry mine.”
 
Dick dropped the paddle in the bottom of the canoe and in a twinkling had flung the sinker into the crystalline water. It took Harvey a little longer, but he did it, with a number of seconds to spare. They could well affect not to be aware of the aerocar, though it was sailing low down, since it moved silently, and true fishermen are always absorbed in the work, or rather pleasure, of trying to woo a bite from the finny inhabitants below[148] the surface. Neither seemed to look up, but none the less they kept a stealthy watch for the monoplane in which they were interested.
 
Professor Morgan gave a thrilling exhibition of his machine’s capability and his skill in handling it. He made a sweeping curve which took him past the fishermen, swooping gracefully to the right and to the left at a height of less than a hundred feet. When he was nearest them he shouted:
 
“Hello, there! What are you doing?”
 
Harvey Hamilton just then was excitedly pulling at his line as if he had a bite and was more anxious to land his catch than to do anything else. Dick suspended his occupation and looked up.
 
“Can’t you see we are fishing?” was his fitting reply in the form of a question.
 
“You are watching me,” insisted the aviator, as he made another circle and came nearer.
 
“What do we care about you? You are scaring away the fish; I wish you would clear out and leave us alone.”
 
“Who is that with you?”
 
“Bill Jones, from Squedunk; he hasn’t much sense and if you don’t look out he’ll take a shot at you with his revolver, and if he doesn’t I will!”
 
And Dick dropped his fishing line over the edge[149] of the canoe, picked up his rifle and pointed it at the loony inventor.
 
“Get!” he commanded, “before I fire!”
 
The demonstration was unexpected, and scared Professor Morgan. Had it not been done at the psychological moment, it is likely he would have approached still closer and forced Harvey to disclose himself. The youth was in a tremor, but it was hard for him to restrain his merriment over the rank bluffing of his brother. The Professor yanked his levers and with his feet abruptly turned the rudder so that his machine shot off at a tangent at an amazing rate of speed. Instead of turning back over his course, he made for the wooded, rocky, mountainous country which had been his destination when he believed he was not under the eye of any one. As soon as he was beyond distinct vision, Harvey dropped his fishing line and brought his field glass into use.
 
“Keep an eye on him as long as he’s in sight,” warned Dick, who also laid his line aside and turned to watch the aviator. The latter held to a direct course for half a mile or more, by which time he was above the section where the brothers believed Bohunkus Johnson was kept in confinement.
 
“He seems to have stopped,” said Dick.
 
“He has; he is descending.”
 
[150]Holding his machine in poise for a minute or two, Harvey saw it dropping down like a weight suspended at the end of a rope. It disappeared behind a mass of rocks and amid a group of large trees covered with exuberant foliage.
 
“It looks as if that is the spot for which we are hunting,” said Harvey lowering the glass.
 
“All the same it isn’t; it’s a trick meant to make us believe it is. Professor Morgan may be crazy regarding aeroplanes, but he isn’t in a good many other things. It has become a game of hide and seek between us.”
 
Conceding this to be the truth, our young friends had to decide upon their next step.
 
“If we land and go to the place, he will know we are more interested in him than he thinks we ought to be. He is watching us from where he landed.”
 
“And if we go there we shall not find Bunk. I do not think he is anywhere near. Meanwhile, the best thing we can do is to keep on fishing. Doubtless he has a glass and is scrutinizing us like a cat watching a mouse. Let’s drop our lines into the water.”
 
They did so and a minute later Harvey felt a tug at his hook. Drawing in his line, he landed a plump bass that must have weighed nearly two pounds.
 
[151]“If the Professor has noticed that,” remarked the younger, “it will help him to believe we are no more than we pretend to be; but, Dick, I don’t understand why he doesn’t shut us off from interfering with him.”
 
“How would he do it?”
 
“Pick up Bunk and carry him away.”
 
“Where to?”
 
“He could keep him in his workshop for the little while that must pass before he starts on his grand flight.”
 
“The Prof............