French submarine lost for over half-a-century located in Mediterranean

[Polybius]

30. The USS Cyclops story is very interesting

From wiki:

Cyclops had three sister ships, all commissioned in 1913, which were all ill-fated.

USS Jupiter (AC-3) was converted to an aircraft carrier between 1920 and 1922 and was recommissioned as USS Langley (CV-1). Langley was the first American aircraft carrier and was vital in developing United States naval aviation capabilities. She was converted again between 1936 and 1937 as a seaplane tender and redesignated as AV-3. She was stationed in the Philippines in December 1941 and departed for Australia following the Japanese attacks on Pearl Harbor and the Philippines. On February 27, 1942, while ferrying fighter planes to Southeast Asia, she was attacked by Japanese aircraft and was hit by five bombs, causing critical damage. After her surviving crew members were rescued, Langley was scuttled by torpedoes fired by her escorting destroyers.

USS Proteus (AC-9) was sold on March 8, 1941, became part of the Canadian Merchant Navy, and was lost at sea without a trace, probably in or near the Caribbean Sea, sometime after November 25, 1941.

USS Nereus (AC-10) was sold to the Aluminium Company of Canada on 27 February 1941. She was lost without a trace after departing Saint Thomas, U.S. Virgin Islands, on December 10, 1941, with a load of bauxite ore (for making aluminum).