A fair, delicately-molded hand, on which glittered gems worth a raja's loyalty, was extended in the direction of the sea.Half a mile out, where the light ripples melted away into a blue and white haze upon the water, a small black smudge, like the back of a porpoise, seemed to be sliding along the surface.But it was not a porpoise, for out of it there rose a thin, black shaft, scarcely higher than a flag-staff, and from the top of this thin shaft there trickled a faint wreathing line of smoke, just visible against the background of sky and sea."It is a submarine! What is it doing there?"The exclamation, followed by the question, came from the second, perhaps the fairer, of two women of gracious and beautiful presence, who were pacing, arm linked in arm, along a marble terrace overlooking a famous northern strait.The terrace on which they stood formed part of a stately palace, built by a king of the North who loved to retire in the summer time from his bustling capital, and gather his family around him in this romantic home.From here, as from a watch-tower, could be seen the fleets of empires, the crowded shipping of many a rich port and the humbler craft of the fisherman, passing and repassing all day long between the great inland sea of the North and the broad western ocean.