By: HISTORY.com Editors

1913

Inventor Rudolf Diesel mysteriously vanishes

Published: November 13, 2009Last Updated: May 27, 2025

On September 29, 1913, Rudolf Diesel, inventor of the engine that bears his name, disappears from the steamship Dresden while traveling from Antwerp, Belgium to Harwich, England. On October 10, a Belgian sailor aboard a North Sea steamer spotted a body floating in the water; upon further investigation, it turned out that the body was Diesel’s. There was, and remains, a great deal of mystery surrounding his death: It was officially judged a suicide, but many people believed (and still believe) that Diesel was murdered.

Diesel patented a design for his engine on February 28, 1892,; the following year, he explained his design in a paper called “Theory and Construction of a Rational Heat Engine to Replace the Steam Engine and Contemporary Combustion Engine.” He called his invention a “compression ignition engine” that could burn any fuel—later on, the prototypes he built would run on peanut or vegetable oil—and needed no ignition system: It ignited by introducing fuel into a cylinder full of air that had been compressed to an extremely high pressure and was, therefore, extremely hot.

Such an engine would be unprecedentedly efficient, Diesel argued: In contrast to the other steam engines of the era, which wasted more than 90 percent of their fuel energy, Diesel calculated that his could be as much as 75 percent efficient. (That is, just one-quarter of their energy would be wasted.) The most efficient engine that Diesel ever actually built had an efficiency of 26 percent—not quite 75 percent, but still much better than its peers.

By 1912, there were more than 70,000 diesel engines working around the world, mostly in factories and generators. Eventually, Diesel’s engine would revolutionize the railroad industry; after World War II, trucks and buses also started using diesel-type engines that enabled them to carry heavy loads much more economically.

At the time of Diesel’s death, he was on his way to England to attend the groundbreaking of a new diesel-engine plant—and to meet with the British navy about installing his engine on their submarines. Conspiracy theories began to fly almost immediately: “Inventor Thrown Into the Sea to Stop Sale of Patents to British Government,” read one headline; another worried that Diesel was “Murdered by Agents from Big Oil Trusts.” It is likely that Diesel did throw himself overboard—as it turns out, he was nearly broke—but the mystery will probably never be solved.

Timeline

Also on This Day in History

Discover more of the major events, famous births, notable deaths and everything else history-making that happened on September 29th

Related Articles

Art made of code named Kryptos sits on the grounds of the C.I.A. Headquarters in Virginia

Since 1990, the world's top codebreakers have been stumped by a mysterious sculpture called 'Kryptos.'

Marie Sklodowka Curie (1867 - 1934) in her laboratory. She shared a Nobel Prize in Physics in 1903 with her husband Pierre for their work in radioactivity. In 1911 she became one of the few people to be awarded a second Nobel Prize, this time in chemisty for her discovery of poloium and radium. Her daugther and son-in-law also shared a Nobel Prize for Chemistry in 1935 for work in radioactive materials. He went on to become the first chairman of the French atomic energy commission. France.

Marie Curie won not just one Nobel Prize in her lifetime, but two, for her groundbreaking work in radioactivity.

While the advent of train travel altered previously held concepts of time and distance, learn about 10 railways and train journeys that also changed the course of history.

About the author

HISTORY.com Editors

HISTORY.com works with a wide range of writers and editors to create accurate and informative content. All articles are regularly reviewed and updated by the HISTORY.com team. Articles with the “HISTORY.com Editors” byline have been written or edited by the HISTORY.com editors, including Amanda Onion, Missy Sullivan, Matt Mullen, Christian Zapata and Cristiana Lombardo.

Fact Check

We strive for accuracy and fairness. But if you see something that doesn't look right, click here to contact us! HISTORY reviews and updates its content regularly to ensure it is complete and accurate.

Citation Information

Article title
Inventor Rudolf Diesel mysteriously vanishes
Website Name
History
Date Accessed
August 22, 2025
Publisher
A&E Television Networks
Last Updated
May 27, 2025
Original Published Date
November 13, 2009

History Every Day

Sign Up for This Day in History

Uncover fascinating moments from the past every day! Learn something new with key events in history, from the American Revolution to pop culture, crime and more.

By submitting your information, you agree to receive emails from HISTORY and A+E Global Media. You can opt out at any time. You must be 16 years or older and a resident of the United States.More details: Privacy Policy | Terms of Use | Contact Us