HMS Pathfinder

HMS Pathfinder was the lead ship of her class of two British scout cruisers, and was the first ship ever to be sunk by a self-propelled torpedo fired by submarine (the American Civil War sloop-of-war USS Housatonic had been sunk by a spar torpedo). She was built by Cammell Laird, Birkenhead, launched on 16 July 1904, and commissioned on 18 July 1905. She was originally to have been named Fastnet, but was renamed prior to construction. During the beginning of World War I, Pathfinder was sunk on 5 September 1914 by the German U-boat U-21.

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