Automotive progress is not always led by engineers and designers. Sometimes it’s made by grocers. In 1860 a travelling grocery salesman called Nikolaus Otto came across an account of a ‘reciprocating engine’ built in Paris by one Jean-Joseph Lenoir, running on the gas then used to light the streets of the Cité de Lumière.
Intrigued, he built a replica of Lenoir’s engine and started to investigate how it might be improved: you might say that there was some room for it – Lenoir’s monster put out all of 2hp from its prodigious 18-litre capacity. In so doing, Otto hit upon the idea of compressing the air-fuel mixture before igniting it. Undeterred by his first compressed-charge engine blowing up after running for only a few minutes, our intrepid salesman persisted, and in 1876 finally perfected what we now know as the four-stroke Otto-cycle engine.
