Oliver Evans (1755-1819) was a Delaware-born inventor who pioneered the high-pressure steam engine and created the first continuous production line. Evans was born in Newport, Delaware, and received little formal education before being apprenticed to a wheelwright when he was sixteen. When he was twenty-two, Evans became a specialist in forming the fine wire used in textile cards, which were used to comb fibers in preparation for the spinning process to make thread or yarn. In order to increase the efficiency of this process, Evans invented a machine that would bend wire into teeth and cut them off rapidly to aid the assembly of cards. Although he was unable to find financial backing to commercialize his invention, his invention inspired card manufacturing innovations over the next two decades.

In 1784, Evans tackled another major industrial production problem, the age-old process of grinding grain. Working with his brothers at a mill they built in Newport, Delaware, Evans created a production line with conveyors, elevators, and weighing scales that were automatic. Labor was required only to set the mill in motion; power was supplied by waterwheels, and grain was fed in at one end and emerged at the other end as finished flour, a system that was much improved over the labor-intensive existing method and resulted in reducing costs by fifty percent.

In 1790, Evans added a third invention, a high-pressure steam engine. He continued to work on this for the next several years, envisioning both a stationary engine for industrial purposes and an engine for land and water transport. In 1801, he built a stationary engine that turned a rotary crusher to produce pulverized limestone for agricultural purposes. By 1805, Evans had completed his new type of steam-engine scow, called the Orukter Amphibolos, or amphibious digger. In its machinery, it embodied the chain-and-buckets principle of his automatic flour mill. Equipped with wheels, it ran on land as well as on water, making it the first powered road vehicle to operate in the United States.

In 1806, Evans turned his attention once more to the commercialization of his inventions. He established the Mars Iron Works, where he made more than a hundred steam engines that were used with screw presses for processing cotton, tobacco, and paper. Additionally, the Mars Works produced cast iron fittings, milling and farming machines, and casting naval cannons during the War of 1812.

Over his life, Evans wrote several guides, including Young Mill-Wright and Miller's Guide and The Abortion of the Young Steam Engineer's Guide.

Evans married Sarah Tomlinson (1763-1816) in 1783. The couple had eight children: Elizabeth, George, Ann, Rachel, Sarah, Oliver, Cadwallader, and Oliver Jr. Sarah died in 1816, and two years later, he married Hetty Ward (1790-1824). On April 11, 1819, news reached him in New York that the Mars Works in Philadelphia had burned down. Four days later, Evans died, following a month of illness.