In Telegraph letters published today, Dr Keith Ray of Marlow, Buckinghamshire, delivers a sharp blow to "the myth" that Rudolph Diesel invented the diesel engine:
Diesel filed a patent in February 1893 for an engine that would (or could in theory at least, as he didn't build one for a further four years) run on coal dust, with ignition taking place through the heat of compression. He didn't finally make a working machine until 1897, which blew up and nearly killed him.
As early as 1891 (two years before even Diesel's dubious coal-burning patent), Herbert Akroyd Stuart, an Englishman, built the first compression-ignition oil (not coal dust) engine in Bletchley, six years before Diesel built any engine. He leased the rights to Richard Hornsby, who by 1892, five years before Diesel's disastrous prototype, had a diesel engine working in a water-works. By 1896, they were building diesel tractors and locomotives in some quantity.
The Oxford Dictionary of National Biography confirms Dr. Ray's points, but Diesel receives all the recognition. Why? For one thing German companies interested in making millions ran with Diesel's invention, which he had beautifully documented with precise engineering drawings. For another Diesel's engine was capable of producing high speeds. And third – just an idea for the poets among us – Diesel's name has a powerful, oily sound.