ten o'clock
But there was no wind ; the black sea was calm save for a long , hardly perceptible swell . A strong swimmer and in superb condition , Dan felt no anxiety about being able to make the distance . There was danger , however , that a shark would run across him , or that he could not find a landing place upon the rocky shore . Four bells had rung when he had seen the first flash ; it had been just ten o'clock . And it was some four hours later that Dan touched bottom and waded wearily up a bit of smooth hard beach , through palely glittering phosphorescent foam . He rubbed the brine from his tired limbs , and sat down for a time , in a spot where a fallen boulder sheltered his naked body from the cool morning wind . In a few moments he rose , flexed his muscles and peered through the starlit darkness for a way up the cliff behind the beach .