Rudolf Christian Karl Diesel was born on March 18th 1858 in Paris to Bavarian parents, Theodor and Elise Diesel, the second of their three children. Theodor had immigrated to France from Germany around 1850, he had a small leather working business there and provided a merge income for his family. Rudolf, a shy but bright child, spent most of his childhood in France. He exhibited an aptitude in mechanics from and early age but also excelled in mathematics and languages (he spoke three; German, French and English).
During the Franco-Prussian War of 1870/71 Germans became political-undesirables in Paris and so the family left for London. Theodor found it very difficult to obtain work there and when an uncle back in Augsburg, Germany, offered to take the now twelve-year-old Rudolf his parents agreed. Rudolf was entered into a three year programme at a technical college in Augsburg where he again excelled, after his parents returned to Paris in 1871 Rudolf stayed in Germany where he graduated as top of his class. He returned to Paris but after the tragic death of his elder sister returned again to Augsburg where he enrolled on a mechanical engineering program and again graduated top of his class.
Rudolf was awarded a scholarship to attend the Munich Institute of Technology where he studied thermodynamics under Prof. Carl von Linde, the inventor of the ammonia refrigeration machine and the man who devised the first practical method of liquefying air. It was here that Diesel began to think about his ides for a “heat engine”.
At the time the dominant source of mechanical power was from the steam-engine but this suffered from a very poor efficiency, between six and ten per-cent, with less than one-tenth of the energy available to do useful work relative to the energy in fuel it was fed. Diesel asked himself if the heat could not be turned directly into mechanical energy rather than via the steam.
Diesel graduated from Munich Institute of Technology in 1880 and became an apprentice pattern maker and engineer in Winterthur, Switzerland but he was quickly moved to Paris where his old teacher Carl von Linde arranged a job for him in the city’s first ice making factory where he was quickly promoted to plant manager.
Here in Paris he filed for his first patent (on the “production of ice in glass containers”), became a connoisseur of the arts, a linguist, and a social theorist. He married Martha Flasche in 1883 (they had three children, Eugen, Hedi and Rudolf). Carl von Linde arranged a franchise for Diesel to sell Linde’s refrigerators in Southern Europe and the young family moved to Berlin.
In 1892 from Berlin, Diesel filed for a patent at the Imperial Patent Office in Germany and within a year he was granted Patent No. 67207 for his proposed engine. This is also when he wrote is paper “Theory and Construction of a Rational Heat Engine to Replace the Steam Engine and Contemporary Combustion Engine” which outlined an engine which could burn any fuel ignited not by a spark but by the temperature caused by the compression of gasses; a similar concept to refrigeration.
At this time the engine was only a concept, Diesel need to build a prototype. With the help of the Augsburg Machine Works among others he produced his first working prototype in February 1894. Diesel had enormous technical problems to overcome, he continued to build prototypes, modify designs and experiment with fuels such as gasoline, kerosene and lighting-gas for several years. On 31st December 1896 Diesel ran the first engine he considered to be a success.
Diesel had traded the licence to produce his new engine in Germany with his investors but as word of his new invention spread he started selling licences to build and refine the design across the world. He sold the American patent rights to the brewer Adolphus Busch for one-million marks. As companies bought licenses Diesel quickly became a very wealthy man, he established a company, the General Society for Diesel Engines, in 1898 to mange the business, it bought the rights to his engine and assumed full control, paying Diesel 3.5 million German Marks for this (a massive amount of money).
All was not rosy however, years of constant work were having a serious effect on Diesel’s health, he suffered severe headaches and exhaustion and gout and was sent to various sanatoriums for rest. He suffered exhausting patent disputes, the Diesel engine not being the first to employ the principle of compression ignition. In addition, while diesel had been very successful in his own business he had also made some terrible investments and lost millions in other peoples ventures.
At the Paris exposition of 1900 a diesel engine was exhibited where it won the Grand Prize. Myth has it that it was exhibited by Diesel himself but in reality at the request of the French Government it was exhibited by the Otto Company, however it is true ran wholly on peanut oil. To quote Diesel himself:
“…at the Paris Exhibition in 1900 there was shown by the Otto Company a small Diesel engine, which, at the request of the French Government, ran on Arachide (earth-nut or pea-nut) oil, and worked so smoothly that only very few people were aware of it. The engine was constructed for using mineral oil, and was then worked on vegetable oil without any alterations being made.”
This is often cited as evidence of Diesel’s foresight on bio-fuels but it seem it was more to do with h French Government’s desire to enable their African colonies to become more self sufficient and les reliant on imported fuel. Diesel again:
“The French Government at the time thought of testing the applicability to power production of the Arachide, or earth-nut, which grows in considerable quantities in their African colonies, and which can be easily cultivated there, because in this way the colonies could be supplied with power and industry from their own resources, without being compelled to buy and import coal or liquid fuel.”
However it is true that Diesel was a strong advocate of the use of bio-fuels, if only for his original desire for the engine to be operational almost anywhere on almost any fuel. In 1911 he said:
“The diesel engine can be fed with vegetable oils and would help considerably in the development of agriculture of the countries which use it”
And in 1912:
“The use of vegetable oils for engine fuels may seem insignificant today but such oils may become, in the course of time, as important as petroleum and the coal-tar products of the present time…motive power can still be produced from the heat of the sun…even when the natural stores of solid and liquid fuels are completely exhausted”
Despite the publishing of another book in 1912, Die Enstebung des Dieslmotors, recounting the history of his invention, Diesel’s debits continued to rise, he seemed to be sinking into a deeper depression over his financial difficulties. On the evening of 29th September 1913 he boarded the SS Dresden to cross the English Channel from Belgium to England to attend a meeting of the Directors’ of the British Diesel Company. He boarded the ship with three fellow directors; the three men took dinner on board and later strolled on deck before retiring to their cabins around 10pm, arranging to continue their conversation in the morning – Diesel was later described as “cheery and buoyant”. When, as instructed, he was called at 6:15am the next morning he could not be found, his bed had not been slept in and his night shirt was laid out ready and his watch was next to the bed. Several through searches were carried out but he was not to be found, he had utterly vanished.
The British, European and US press had a field day suggesting that Diesel had been murdered by big oil business, the British Secret Service, the Germans or the French.
On October 10th 1913 his body was found dead in the water off the Dutch coast. Following the custom of the time, personal effects were removed from the decomposing body and it was returned to the sea. Diesel’s son identified the effects as belonging to his farther.
Considerable speculation has grown around Diesel’s death; no autopsy or official investigation was ever carried out, he had marked an X by that date in his diary, he left no suicide note and no will. However he did leave an overnight valise with his wife with instruction not to open it until the following week; it contained twenty-thousand German marks in cash and bank statements showing that they were nearly broke.
Rudolf Diesel has no known grave.
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