Rudolf Diesel is probably best known as the inventor of the engine which bears his name, but his puzzling and seemingly inexplicable disappearance on September 29, 1913 left behind a mystery nearly as enduring as the legacy of his engineering achievements.
After working as an engineer developing everything from refrigerators to steam engines, Diesel ultimately filed the patent for his groundbreaking engine in 1892. In the years to follow, the diesel engine would become a major backbone of the manufacturing and trucking industries.
Then, one night in 1913, while crossing the English Channel aboard the steamer Dresden, Rudolf Diesel disappeared without a trace.
On September 29, 1913, Diesel boarded a ship bound from Antwerp to London. Witnesses at the time said that he had dinner on board and retired to his cabin at around 10:00 pm, requesting a wake-up call at 6:15 the following morning. However, Diesel’s bed was never slept in, and his nightclothes were found laid out upon the undisturbed blankets of his mattress.
Official accounts concluded that Diesel perished that night. Some say he fell overboard during a midnight stroll on the decks–Diesel was a known insomniac–but there are no reports of rough seas or inclement weather that could have contributed to such a fall. The more common version of events says that the 55-year-old man threw himself into the sea to escape his failing health, his mounting debt, or whatever else may have been plaguing him. However, there are other theories.
Diesel’s eponymous engine was instrumental in the development of the German U-boats, which would play a major role in both the First and Second World Wars. Some believe that German agents snuck aboard Diesel’s boat and killed him in order to prevent him from sharing his inventions with the Brits.
Stories of what happened after Diesel’s disappearance are also varied. Even newspaper accounts of the time couldn’t keep track of the facts of the case, nor the financial security of the Diesel family. The New York Times ran two separate headlines within weeks of each other: one read, “German Inventor Was a Millionaire and His Home Was Happy” while the other announced, “DIESEL FAMILY IN STRAITS: Missing Inventor Said to Have Left Them in Extreme Need”.
Indeed, the Diesel family became quite rich as a result of Rudolf's patents, Rudolf himself may have been a better engineer than money manager. Reports suggested that he was in considerable debt prior to his disappearance—leading some researchers to suspect that there was more to his vanishing than met the eye.
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Adding to the mystery, Diesel’s body was never officially recovered. However, there are two accounts that may shed some light on his body’s whereabouts after his disappearance. Ten days after he vanished, the crew of a Dutch boat fished a man’s body out of the sea near Norway. The remains were too decomposed for identification, but they took the body’s belongings, which were later identified by Diesel’s son as belonging to the deceased inventor. On October 14, 1913, another report of what may have been Diesel’s body surfaced, near the mouth of the Scheldt river, but the person who found it was forced to throw it back overboard due to rough weather.
Besides the lack of a body, other strange circumstances surrounding Diesel’s disappearance have led to speculation as to the nature—and, indeed, facts—of his demise. According to Greg Pahl, author of the book Biodiesel: Growing a New Energy Economy, Diesel gave his wife a bag shortly before he left on his trip, with instructions not to open it until the following week. Inside were financial statements indicating their debt, as well as a substantial sum in German marks.
Perhaps more ominous still, Diesel had drawn a small cross in his diary next to the date he disappeared. Whether this was an indication of his intent to take his own life, knowledge of his impending murder or held some other significance, we may never know.
These strange accounts, along with a few others, have led some to hypothesize that Diesel neither killed himself nor was murdered, but instead faked his own death and went into hiding. In fact, by the spring of 1914, even the New York Times was reporting on what turned out to be an unsubstantiated rumor that the inventor was alive and well in Canada.
Rudolf Diesel was inducted into the Automotive Hall of Fame in 1978, decades after he vanished without a trace. In a case so long cold, the full story will probably never be known, but now that you’ve heard the tale of Rudolf Diesel’s mysterious disappearance, you may never look at a diesel engine the same way again.
Featured photo: Wikimedia Commons; Additional photo: Alchetron