Akroyd Stuart and Diesel make compression ignition practical

Akroyd Stuart and Rudolf Diesel followed different routes toward practical compression ignition. Stuart's patents combined a heated vaporizer, a four-stroke cycle, fuel injection, and ideas about compression ignition, but Hornsby still had to fund extensive experimental development before the engine succeeded. Stuart's technical education and place in a family engineering firm support the broader explanation of how knowledge and industrial capacity combine. Diesel began from more ambitious thermodynamic theory, some of which proved impracticable before Maschinenfabrik Augsburg-Nurnberg developed a working machine in 1897. Its roughly 500-psi cylinder compression, much higher-pressure air injection, and rapid international licensing explain why Diesel's name became attached to the wider propulsion family. Diesel himself claimed that the engine had broken coal's monopoly.