In a storied long-distance swimming career, Tammy van Wisse has conquered the English Channel, Scotland's frigid Loch Ness and some of the world's most treacherous ocean straits in and around her native Australia. Along the way, she's collected a passel of world records and victories in grueling swim marathons, including a record-breaking loop around Manhattan in 1997. Yesterday, the 37-year-old van Wisse returned to local waters to retrace the strokes of her childhood hero, pioneering swimmer Ger trude Ederle, the first woman to make the 22-mile crossing between Lower Manhattan and Sandy Hook. Ederle's record time for the crossing --...