But it is difficult to believe that the sea-floor could have subsided to such an extent in recent times.
The darkness on the sea-floor was too thick, the wavering shadows too deceptive.
The tests of other creatures largely calcareous may well have been dissolved before reaching the sea-floor.
Hemmy had a glimpse of the NX-1 lying silent and apparently lifeless on the sea-floor, a gaping hole in her bow!
They had ropes, and in seconds they'd lashed us down to the sea-floor.
