noon
It was the bottom of the sea , and at no great depth , not more than a few fathoms below their feet . Such shallow water could not be far from the shore . Reassured , and encouraged by the thought , they once more renewed their exertions , and continued to paddle the spar , taking only short intervals of rest throughout the whole of the morning . Long before noon they were compelled to desist . They were close to the tropic of Cancer , almost under its line . It was the season of midsummer ; and of course at meridian hour the sun was right over their heads . Even their bodies cast no shadow , except upon the white sand directly underneath them , at the bottom of the sea .