Andy continued to make use of the pair of glasses that magnified objects in the far distance so wonderfully that a man could have been recognized easily a mile away, and perhaps much further, if the air were real clear.

Now and then he turned them to the right.  The beautiful lake always attracted him very much like a magnet would, whenever he had a chance to look out over its glistening bosom.

And there was the little steamer, just as Frank had said; why, he could even distinguish Todd Pemberton up in the pilothouse, grasping his wheel and guiding his charge among the shoals that were charted in the northern end of the lake as dangerous, that is, for green hands at the tiller or wheel of a boat propelled by sails, steam or gasolene.

They were moving in a line that would carry them up along the shore, and consequently every minute they drew nearer the small lake steamer that was heading toward them.

Passengers could be seen on its deck, and possibly every eye was glued just at that particular moment on the aeroplane that was buzzing go steadily northward; perhaps it might have been the first time some of these people had ever seen such an interesting object; but in the region around Bloomsbury it was by now a common sight, with such enterprising young air pilots as the Bird boys and Percy Carberry in the field almost every decent day.

All at once Frank was heard to utter an exclamation.

“Turn your glasses straight ahead, and see what that can be fluttering among the bushes at Norton’s Point, Andy!” he called out hastily.

When the other had swung around, and covered the region spoken of, he quickly gave the desired information.

“Somebody seems to be shaking a handkerchief or something else white,” he observed.  “And it don’t look like just waving at the steamer either, for they do it after a system, as we would signal with wigwag flags.  There, I counted seven times he did it; then comes a halt, and one, two, three times, another halt; and once more he starts in, this time three, four, five, and then stops.  Now, what do you suppose the fellow means by that, and who can he be waving to, Frank?”

“You’d expect it might be some one out on the lake; can you see any small boat in sight, Andy; or any one waving back from another point?”

“Not a thing, as far as I can see,” replied the boy with the marine glasses.

“Suppose you try the steamer, then,” suggested Frank, meaningly.

Immediately Andy gave an exclamation of astonishment.

“I see a signal moving, Frank, and it seems to be copying the one on shore,” he hastened to remark, excitedly.

“Where does it come from, the passengers that I saw pushing up against the rail, and staring at us; are any of them interested, do you think?” continued Frank, who just then could not turn his head to look, but must depend on his chum.

“Well, no,” answered Andy, “it seems to come from the pilothouse, and must be Todd Pemberton, himself.”