Question

Which unit is used for measuring depth of sea?

Answer 1

the unit is FATHOMS

measured using FATHOMETER or SONIC DEPTH FINDERS

Answer 2

A deep sea assist the heaviest of sounding lead and it used in the water exceeding 100 fathoms in depths.

This method has well superseded by the sonic depth finder for measuring the mechanically the depth of water beneath a ship.

One version of which is fathometer. On the other hand the record mad by such device is fathogram.