4th August 1921
U.S. Navy submarine USS S-12 is launched.
Ship Losses:
Ellen Benzon (Denmark) The schooner was driven ashore at Seyðisfjörður, Iceland and was wrecked. Her crew were saved.
Salti I (Italy) The coaster struck a mine in the Adriatic Sea off the coast of Foggia and sank with the loss of a crew member. Survivors were rescued by
Mikali ( Greece).