By the late 1800s, a handful of experimenters around the world were closing in on the riddle of powered flight. They could fly a plane into the air, but they still couldn't control it - keep it from pitching forward, turning side to side, or rolling. The Wright Brothers solved pitching and turning, but rolling eluded them. One day in the cycle shop in 1899, Wilbur picked up an empty bicycle tube box and adsentmindedly twisted either end. In that instant, he saw the solution: warping one wing down while warping the other up would keep the plane from rolling. Four years of study and experimentation lay ahead, but the Wrights were on their way to being the first to fly a heavier-than-air machine.