The tall man straightened up suddenly, and his manner was that of one who had been startled. Jack knew why he should act in this way, for the same sound that had come to the man’s ears had also reached his.
It was a shrill whistle, twice repeated, and it came from the same direction in which the two men had gone a short time before.
Undoubtedly it was a signal denoting urgent need of haste. The actions of the tall smuggler would indicate as much; for he dashed out of the cabin like a shot, and Jack heard the thud as he threw the shovel into the shrubbery surrounding the lone hut.
Then followed the crashing of bushes as the man started by a circuitous route toward the upper end of the island. He must know every foot of the ground, and by taking to the open beach, could gain a given point much sooner than one who kept to the thick undergrowth.
Jack saw the lantern had been hastily dropped, though it was still burning. He was trembling with excitement, and feeling very much as though he wanted to yell at the top of his voice as he picked up this abandoned tool of the discovered smugglers.
He could hear the boys talking down there where the trio of motor boats were anchored; and could imagine how they must be wondering what all the racket on the island meant; while Josh would doubtless start in to tell them how he, Jack, had persisted in going ashore.
Some one was coming, for Jack could hear quick footsteps near by. He still held his Marlin gun, but was loath to even threaten to use it. Nor was there any need, for a moment later the moving dim figure took form, and proved to be no other than Professor Marshland.
At sight of Jack standing there, lantern in one hand and gun in the other, the gentleman allowed something like a grim smile to creep over his face, even as he came hurrying up, almost out of breath from his exertions.
“Do you know what it all means, Jack?” demanded the other, as soon as he reached the side of the boy.
Jack nodded his head eagerly.