7 SEPTEMBER 1776 – David Bushnell, an American inventor, began building underwater mines while a student at Yale University. Deciding that a submarine would be the best means of delivering his mines in warfare, he built an eight-foot-long wooden submersible that was christened the Turtle for its shape. Large enough to accommodate one operator, the submarine was entirely hand-powered. Lead ballast kept the craft balanced. Ezra Lee piloted the craft unnoticed out to the 64-gun HMS Eagle in New York Harbor on September 7, 1776. As Lee worked to anchor a time bomb to the hull, he could see British seamen on the deck above, but they failed to notice the strange craft below the surface. Lee had almost secured the bomb when his boring tools failed to penetrate a layer of iron sheathing. He retreated, and the bomb exploded nearby, causing no harm to either the Eagle or the Turtle. Other attempts were tried but all failed rochestermilitary.com