The First Diesel Engine

In the 1890s, Rudolf Diesel invented an efficient, compression ignition, internal combustion engine that bears his name. Early diesel engines were large and operated at low speeds due to the limitations of their compressed air-assisted fuel injection systems.

Defining innovations can be challenging.  Currently we see mass produced gas trucks and mass produced diesel trucks.  Powerstroke, Cummings, Durmax but what was the original use?  It was not until the 1920's that commercial units were able to use the design and the 1930's for passenger units.  it took 13 years to produce the first functioning design as steam power was the most prominent source for large industries.  Now we have seen diesel engines revolutionize.  
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