Edison, Bell, Ford, Wright—all immortal names in the pantheon of inventors. “Diesel,” however, evokes a sparkless engine and the compressed fuel that powers it, not its eponymous creator, let alone his extraordinary scientific and geopolitical importance. Rudolf Diesel, sadly, has mostly been lost to history.
No longer. In Douglas Brunt’s superb biography, the fin-de-siècle Franco-German Diesel reemerges in vivid color as an ingenious engineer, an aggressive businessman, and a fully formed innovator whose life’s work strongly influenced the First World War and fundamentally remade numerous industries. To top it off, Diesel perished mysteriously shortly before the conflagration that his (fire-free) engine helped ignite.
Calling the diesel engine “a quantum leap forward in humankind’s ability to convert a substance into power,” Brunt unapologetically declares it “the most disruptive technology in history.” Edison himself characterized it as “one of the great achievement of mankind.” Winston Churchill dubbed diesel-powered ships “the most perfect maritime masterpiece of the century.” It’s not surprising, therefore, that Diesel’s pivotal creation got him crosswise of giants like John D. Rockefeller and Kaiser Wilhelm II, fueling speculation about the cause of his untimely demise.
Brunt’s skillful retelling of Diesel’s life and times has an almost cinematic feel: a young man, torn between two countries, against a backdrop of brewing international conflict, confronting entrenched business interests and overcoming immense technical skepticism at the peak of the Industrial Age.
Born in Paris in 1858 to German parents, Diesel lived a mostly charmed life in the City of Light. He spoke perfect French and enjoyed visiting the Conservatoire national des arts et métiers near Le Marais. And at the 1867 World’s Fair, he encountered, significantly, the first coal-gas internal combustion engine, which was twice as efficient as its steam-powered predecessor.
In 1870, when the Franco-Prussian War sparked virulent anti-German sentiment, the Diesel family sought exile in London. Rudolf’s parents ultimately sent the teenager to Augsburg, Germany, a small industrial Bavarian city 50 miles northwest of Munich, where he apprenticed and eventually enrolled in technical university.
While engrossed in study, Diesel grew obsessed with a single, central question, recorded for posterity in one of his notebooks: “Can one build steam engines which realize the perfect cycle process without their being very complicated?” After earning his degree, Diesel went to work at the Paris factory of his mentor, Carl von Linde, a refrigeration pioneer—Diesel himself would later invent the ice cube—while continuing to pursue his primary research focus.
After marrying and starting a family, Diesel relocated to Berlin and then Munich. His son, Eugen, recalled a moment when Rudolf explained to the children the principle behind his obsession by means of a pneumatic cigar lighter—a sparkless, syringe-shaped tool that ignites when its plunger is depressed and compresses the air inside. “Now just imagine that some petrol or petroleum or coal dust were in there instead of the tinder,” Diesel said. “Of course it would have ignited, and the increased gas pressure from this combustion—because heat expands objects and air, too—would naturally push out the piston.”
Diesel continued to refine this concept, both on paper and in the lab. In 1891, he published a 64-page monograph about his engine; in February 1893, he received his first patent on the idea; and in January 1894, he completed his first test engine, which exploded, nearly killing its creator. The inventor received nothing but scorn and disbelief from colleagues and rivals in the industry. As Diesel would later reflect, “publishing my brochure provoked violent criticism, on the average very unfavorable, if not utterly annihilating.”
And so, it wasn’t until 1897 that the tide turned: A then-39-year-old Diesel first submitted his engine to a public test, which it passed with flying colors, recording a mind-blowing 26.2 percent thermal efficiency—more than twice that of the internal combustion engine. In addition, the absence of a spark meant Diesel’s engine ran safer, cleaner, and quieter than gasoline engines.
He and his patrons in Augsburg then inaugurated an international licensing campaign. They began in Scotland, where none other than Lord Kelvin opined that “Diesel’s process of heating the air, simply by compression, to a temperature far above the igniting point of the fuel…supersedes all use of flame or hot chamber for ignition.”
A few months later, Adolphus Busch traveled to Augsburg from St. Louis and became the exclusive licensee of diesel engines in the United States and Canada for the modest cost of $9 million in today’s money.
And the following year, Diesel executed an agreement with Emanuel Nobel, nephew of Alfred, for exclusive engine-building rights in Russia. He signed at least 22 licensing compacts across Europe and North American from 1897 to ’98 alone, and the technology spread as far as Japan and South America.
The new engine’s maritime applications were abundant. In 1903, Nobel became the first to install a diesel engine on a ship: Unlike steamships, diesel-powered tankers required no coal, no stokers, no refueling stops, and little maintenance. Those same characteristics made the new engine especially suitable for the developing technology of submarine craft, and the French navy launched its first diesel-powered submarine in 1904. Brunt surmises that the technology accounted, at least in part, for the success of the Antarctic Amundsen expedition, whereby a Diesel-powered ship enabled the Norwegian to win the race to the South Pole.
Meanwhile, Kaiser Wilhelm II, determined to boost Germany’s nascent naval power, focused his efforts on integrating diesel engines into both surface ships and U-boats, ultimately focusing on the latter when he concluded he would never match British prowess in the former. But Diesel himself grew disaffected with the German war effort and the country’s budding militarism, and as his patents began to expire, he explored partnerships in Britain and the U.S. In 1912, at the peak of the German–British arms race, he co-founded the Consolidated Diesel Engine Company at the behest of Churchill, then First Lord of the Admiralty.
Meanwhile, he embarked on a grand American tour, barnstorming the country to deliver energetic speeches and conferring with innovators such as Edison, Ford, Westinghouse, and Merck. “Nowhere in the world,” he would later tell his colleagues in Munich, “are the possibilities of the prime mover as great as in the United States of America.” But Diesel’s engine, which could run on a wide variety of fuels, threatened the monopoly on light sweet crude held by Rockefeller, then the world’s richest man.
So when Diesel died suddenly in September 1913—nine months before the outbreak of the Great War—after boarding a ship crossing the English Channel from Antwerp to Harwich, speculation abounded. Some fingered the Kaiser or the robber barons as hiring hit men; others trafficked in rumors that Diesel’s faltering health and mounting debts prompted suicide; yet others blamed an accident.
Brunt carefully considers all of these possibilities and arrives at a compelling way of resolving the conflicting evidence. Without spoiling his bold and creative conclusion, it implicates geopolitical intrigue, British intelligence officers, and an abrupt acceleration of the Allied effort to develop advanced submarines.
Brunt dwells in a bit more detail than necessary on the vicissitudes of the inbred, quarrelsome Wilhelmine family line and on Rockefeller’s and Standard Oil’s interesting but not entirely relevant backstory. He might instead have devoted more space to Diesel’s actual development of his groundbreaking technology.
Yet this indispensable book documents just how important Diesel’s innovation—and life—proved. Nowadays, nearly all maritime, rail, and truck traffic are powered by diesel engines, as are roughly 35 percent of the 1.4 billion cars on the road. The global diesel market is valued at more than a trillion dollars. And, for good or ill, the technology transformed modern warfare and international relations. At a moment when mononymic innovators such as Musk, Bezos, and Gates wield outsize influence on global economics and politics, there’s much to ponder in the life, death, and legacy of Diesel, one of their worthiest predecessors.
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