The darkness had so lifted that the friends could distinguish each other's forms quite plainly, and the lad saw that Jack had extended his arm, and was pointing out to sea. The fellow was startled, as he had good cause to be.
Apparently not far off was something resembling a star, low down in the horizon and gliding over the surface of the deep. Now and then it disappeared, but only for a moment. At such times it was evidently shut from sight by the crests of the intervening waves.
It was moving steadily from the right to the left, the friends, of course, being unable to decide what points of the compass these were. Its motion in rising and sinking, vanishing and then coming to view again, advancing steadily all the while, left no doubt as to its nature.
"It's the 'Nautilus'!" exclaimed Rob; "Captain McAlpine is looking for us."
"That's not the 'Nautilus'," said Jack; "for she doesn't show her lights in that fashion. Howsumever, it's a craft of some kind, and if we can only make 'em know we're here they'll lay by and take us off in the morning."
As the only means of reaching the ears of the strangers the two began shouting lustily, varying the cries as fancy suggested. In addition, Jack fired his gun several times.
While thus busied they kept their gaze upon the star-like point of light on which their hopes were fixed.
It maintained the same dancing motion, all the while pushing forward, for several minutes after the emission of the signals.
"She has stopped!" was the joyful exclamation of Rob, who postponed a shout that was trembling on his lips; "they have heard us and will soon be here."
Jack was less hopeful, but thought his friend might be right. The motion of the star from left to right had almost ceased, as if the boat was coming to a halt. Still the sailor knew that the same effect on their vision would be produced if the vessel headed either away from or toward the iceberg; it was one of these changes of direction that he feared had taken place.