James Postlethwaite was a schooner, launched in 1881. She operated out of Arklow after 1909. She was in Hamburg on the day that Britain entered the First World War with its declaration of war against Germany. Her crew was imprisoned and she was impounded and used as a barge to carry munitions. After the war, in difficult economic conditions, she resumed trading. In 1929, a collier collided with, and sunk, her; however she was successfully salvaged.