Four years of searching the depths of the Indian Ocean has failed to locate Malaysia Airlines Flight 370. But the unprecedented seabed hunt for the missing airliner might be close to solving two 19th century maritime mysteries — the locations of two sailing ships that vanished while carrying cargos of coal.

Maritime historians on Thursday published a short list of the possible identities of two shipwrecks found in the course of the initial three-year search for the Boeing 777 that was lost in 2014 with 238 people aboard.

The wrecks were found southwest of Australia in debris fields scattered with coal.