SS Sir William Siemens was a steel-hulled American lake freighter in service between 1896 and 1944. Built in 1896 by the Globe Iron Works Company of Cleveland, Ohio, for John D. Rockefeller's Bessemer Steamship Company, she was the third of three 432-foot-long (131.7 m) lake freighters, each of which shared the unofficial title of "Queen of the Lakes" due to their record-breaking length.