eleven o'clock
Accordingly , he and Mildmay forthwith adjourned to consult the chart and lay off the course ; and ten minutes later the remainder of the party , who were still sitting on deck , awaiting the return of the absentees , became conscious of the fact that the night-breeze had suddenly strengthened ; and when they looked about them in search of an explanation , they saw the sea about three hundred feet beneath them , and the land slipping away into the gloom of the night astern . The travellers had been at sea a week , pottering along on the surface during the day , and rising some three hundred feet into the air at night -- just high enough , in fact , to take them over and clear of the masts of any ships that they might happen to encounter during the hours of darkness -- maintaining a tolerably uniform speed of ten knots through the air -- not counting the acceleration or retardation of speed due to the varying direction and strength of the several winds that they met with . Thus they had been able to sleep at night with wide open ports , to their great comfort and enjoyment , and the manifest improvement of their health , as was particularly exemplified in the case of little Ida , who was by this time as well as even her parents could desire . The hour was eleven o'clock in the forenoon -- six bells , Mildmay called it -- and the ship had been running on the surface for about an hour . The entire party were sitting out on deck under the awnings , amusing themselves in various ways , the two ladies , each with a book on her lap , to which it is to be feared she was giving but scant attention , and Ida , her father , Lethbridge , and the Russian colonel playing bull . It was a most lovely day , the sky without a cloud , the water smooth , and a soft but refreshing breeze was breathing out from the southward . The ship was steering herself , the self-steering apparatus having been thrown into action , as no other craft were in sight .