Early continuous sounding record from acoustic system.Off of OCEANOGRAPHER.C&GS; didn't use recording instruments until late 1930's
4/3/2019 10:44:52 AM
Date: 1939
Credit: Family of Rear Admiral Paul A. Smith, C&GS;
Location: Hudson Canyon area Photo
Subject: Charting
Subject: Soundings
Subject: Bathymetry
Subject: Acoustic
Subject: