from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun depth finder for determining depth of water or a submerged object by means of ultrasound waves
Sorry, no etymologies found.
However this was impossible since the Fathometer concurrently indicated that the ground level was almost 2,000 meters deep.
Fathometer soundings showed it was on a steep upward slope of the continental shelf.
1928 - Fathometer, which measures underwater depth, patented