Oliver Evans

Oliver Evans was an American inventor and engineer from Delaware who worked chiefly out of Philadelphia and became one of the earliest developers of high-pressure steam engines in the United States. Beginning in 1801 he pursued high-pressure designs independently of the British engineer Richard Trevithick, recognizing that a high-pressure engine could be built far smaller than a low-pressure one for the same power output, and by 1803 he had a working prototype with a double-acting cylinder that the Philadelphia newspaper Aurora called the start of a new era in steam engine history. He patented his steam engine in 1804, and his later Columbian Engine, built around 1812 with a straight-line linkage mechanism, became widely used to power steamboats on the Mississippi River. Evans had already designed the first fully automated industrial process, an automated flour mill using bucket elevators and conveyor belts that needed no manual labor to move grain through the milling process.