High Quality Content by WIKIPEDIA articles! HMS Ariadne was a Diadem-class protected cruiser of the Royal Navy. She was built by J G Thompson of Clydebank and launched on 22 April 1898. In March 1913, she was converted to a stokers` training ship and in 1917 was converted to a minelayer and assigned to the Nore Command. She was torpedoed and sunk off Beachy Head by the German submarine UC-65 on 26 July 1917.