four o'clock
This drawback , of little consequence when sun or stars could be seen , assumed the most serious importance when a heavy fog spread over the face of the waters . The set of the current was a guide of a sort , but , as events proved , it misled them . Man is ever prone to over-estimate , and such a slight thing as the lap of water across the bows of a small craft was sure to be miscalculated ; they contrived to steer west , it is true , but with a southerly inclination . At four o'clock , by general reckoning , they were mid-way between island and continent . They were all wide awake , too weary and miserable to sleep . Suddenly a fog-horn smote the oppressive gloom . It drew near .