Joseph “Pat” Shackelford served aboard the S.S. Halo, a Cities Service Oil Co. tanker which was laden with crude oil on her unescorted route in the Gulf of Mexico. She sank May 20, 1942 about three minutes after being struck by two torpedoes from the German U-Boat 506 (Wurdemann). The information is contained in a book “A Careless Word, A Needless Sinking” by Captain Arthur C. Moore (1998), which compiles data about hundreds of merchant ship losses during World War II. According to Moore, the crude-oil laden Halo, owned by Cities Service since 1923, was struck shortly after midnight 50 miles from the entrance to the Mississippi River. Shackelford was the only survivor from his group found by the Mexican freighter Oaxaca. Moore relates that two other survivors were picked up by the British tank Orina and taken to New Orleans. Moore’s book is subtitled: “A History of the Staggering Losses Suffered by the U.S. Merchant Marine, Both in Ships and Personnel, during World War II.”...