The others scrutinized the maze of foot-prints with the same care as had Rob and were forced to come to the same conclusion. There was no question about it—they would have to seek elsewhere for a trace of the lad.
But where?
They gazed about them at the stretch of lone bay or inlet, the sparse scrub grass and vegetation fringing it on the shore side and wheeling sea-gulls swooping and soaring above the shoal waters.
Then Rob's gaze rested carelessly on a closed and seemingly deserted bungalow, occupying the island above them. As his eyes fell on it they suddenly became riveted and then grew wide with surprise.
A stream of smoke was issuing from the fieldstone chimney roughly constructed at one end of the apparently deserted dwelling.
"There's some one living in that bungalow," he exclaimed, as he made the discovery, "maybe whoever it is can give us some clue to where Joe Digby is."
They all gazed intently at the weather-beaten old house from which the paint was scaling, adding to the note of desertion sounded by its closed shutters and forlorn-looking yard.
As they looked, astonished at the idea that the barren structure should actually house a human being, a sudden thought struck Merritt.
"Suppose Jack Curtiss and his gang are there?" he said.
"Hardly likely," rejoined Rob, "however, we'll get over there and find out just who is making that smoke."