Nothing was in sight.

Not a quicksand, not an island.

A vast desert.
Captain Nemo, by the help of his sextant, took the altitude of the sun, which ought also to give the latitude.

He waited for some moments till its disc touched the horizon.

Whilst taking observations not a muscle moved, the instrument could not have been more motionless in a hand of marble.
"Twelve o'clock, sir," said he.