The ship was buried as junk two centuries ago - landfill to expand a bustling little island of commerce called Manhattan. When it re-emerged this week, surrounded by skyscrapers, it was an instant treasure that popped up from the mud near ground zero. A 32-foot piece of the vessel was found in soil 20 feet under street level, amid noisy bulldozers excavating a parking garage for the future World Trade Center. Near the site of so many grim finds - Sept. 11 victims' remains, twisted steel - this discovery was as unexpected as it was thrilling. Historians say the ship,...