The Black rock was one of a number of second hand Scottish built steamers acquired by the Thomas family. She had been raised after being sunk by a steamer Balniel close to Liverpool bar. She was brought to Amlwch, stripped down and modified. While in the dry dock a violent storm caused her to crash through the lock gates. She demolished the lighthouse pier and totally blocked the harbour entrance. Following a refit she was renamed the Eleth after the patron saint of Amlwch. Despite being structurally sound she was very un popular with her crew. in the second world war she was know as Empire Lethe to disguise her true name from crew members. She eventually floundered on 1 February 1951 with a loss of 9 members of her crew