Oliver Evans was born in Newport, Delaware, on September 13, 1755, and as a young man was apprenticed to a wheelwright. At 22 he invented a machine for making the carding teeth used in the textiles industry. Two years later he went into the flour-milling business with two of his brothers. While working at the flour mill, he invented the grain elevator, conveyor, drill, hopper boy, and descender. These inventions essentially automated the flour-milling process to the point that the mill could be run by one person. In the late 1780s the legislatures of Maryland and Pennsylvania granted Evans the exclusive right to the application of these improvements, and the U.S. Congress granted Evans U.S. patents for his flour-milling inventions in 1790. His was only the third patent granted by the U.S. government.

Around 1800 Evans refined the steam engines of his day, developing perhaps the first steam engine constructed...