Rudolf Diesel's engine, patented in 1892, was a monumental leap in efficiency. Unlike gasoline engines, it used compression ignition, requiring no spark plug. This allowed it to run on a variety of fuels, including vegetable oils—a fact he demonstrated at the 1900 Paris Exposition. His disappearance in September 1913 from the steamer Dresden en route to London occurred under deeply suspicious circumstances. He was to meet with the British Navy about using his engines for submarines. Found floati