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The Roots of Progress About the blog • Writing • Speaking • Bibliography • Subscribe • Roots of Progress Institute Why did we wait so long for the bicycle? by Jason Crawford · July 13, 2019 · 11 min read The bicycle, as we know it today, was not invented until the late 1800s. Yet it was a simple mechanical invention. It would seem to require no brilliant inventive insight, and certainly no scientific background. Why, then, wasn’t it invented much earlier? I asked this question on Twitter , and read some discussion on Quora . People proposed many hypotheses, including: Technology factors. Metalworking improved a lot in the 1800s: we got improved iron refining and eventually cheap steel, better processes for shaping metal, and ability to make parts like hollow tubes. Wheel technology improved: wire-spoke (aka tension-spoked) wheels replaced heavier designs; vulcanized rubber (1839) was needed for tires; inflatable tires weren’t invented until 1887. Chains, gears, and ball bearings are all crucial parts that require advanced manufacturing techniques for precision and cost. Design iteration. Early bicycles were inconvenient and dangerous. The first version didn’t even have pedals. Some versions didn’t have steering, and could only be turned by leaning. (!) The famous “penny-farthing” design, with its huge front wheel, made it impossible to balance with your feet, was prone to tipping forward on a hard stop, and generally left the rider high in the air, all of which increased risk of injury. It took decades of iteration to get to a successful bicycle model. Quality of roads. Roads in the 1800s and earlier were terrible by modern standards. Roads were often dirt, rutted from the passage of many carts, turning muddy in the rain. Macadam paving , which gave smooth surfaces to roads, wasn’t invented until about 1820. City roads at the time were paved with cobblestones, which were good for horses but too bumpy for bicycles. (The unevenness was apparently a feature, assisting in the runoff of sewage—leading one Quora answer to claim that the construction of city sewers was what opened the door to bicycles.) Competition from horses. Horses were a common and accepted mode of transportation at the time. They could deal with all kinds of roads. They could carry heavy loads. Who then needs a bicycle? In this connection, it has been claimed that the bicycle was invented in response to food shortages due to the “ Year without a Summer ”, an 1816 weather event caused by the volcanic explosion of Mt. Tambora the year earlier, which darkened skies and lowered temperatures in many parts of the world. The agricultural crisis caused horses as well as people to starve, which led to some horses being slaughtered for food, and made the remaining ones more expensive to feed. This could have motivated the search for alternatives. General economic growth. Multiple commenters pointed out the need for a middle class to provide demand for such an invention. If all you have are a lot of poor peasants and a few aristocrats (who, by the way, have horses, carriages, and drivers), there isn’t much of a market for bicycles. This is more plausible when you realize that bicycles were more of a hobby for entertainment before they became a practical means of transportation. Cultural factors. Maybe there was just a general lack of interest in useful mechanical inventions until a certain point in history? But when did this change, and why? These are all good hypotheses. But some of them start to buckle under pressure: The quality of roads is relevant, but not really the answer. Bicycles can be ridden on dirt roads or sidewalks (although the latter led to run-ins with pedestrians and made bicycles unpopular among the public at first). And historically, roads didn’t improve until after bicycles became common—indeed it seems that it was in part the cyclists who called for the improvement of roads. I don’t think horses explain it either. A bicycle, from what I’ve read, was cheaper to buy than a horse, and it was certainly cheaper to maintain (if nothing else, you don’t have to feed a bicycle). And it turns out that inventors were interested in the problem of human-powered vehicles, dispensing with the need for horses, for a long time before the modern bicycle. Even Karl von Drais, who invented the first two-wheeled human-powered vehicle after the Year without a Summer, had been working on the problem for years before that. Technology factors are more convincing to me. They may have been necessary for bicycles to become practical and cheap enough to take off. But they weren’t needed for early experimentation. Frames can be built of wood. Wheels can be rimmed with metal. Gears can be omitted. Chains can be replaced with belts; some early designs even used treadles instead of pedals, and at least one design drove the wheels with levers, as on a steam locomotive. So what’s the real explanation? To understand this, I dug into the history of the bicycle. The concept of a human-powered vehicle goes back many centuries. The earliest reference I have found is to Venetian engineer Giovanni Fontana, who in the early 1400s described a four-wheeled carriage powered by a driver pulling on a loop of rope connected by gears to the wheels (it’s unclear if he ever even attempted to build such a machine; Fontana sketched a lot of strange things ). Another early concept was described in the book Bicycle by David V. Herlihy : More than three centuries ago, the distinguished French mathematician Jacques Ozanam spelled out the theoretical advantages of a human-powered carriage “in which one can drive oneself wherever one pleases, without horses.” Its owner could freely roam along the roads without having to care for an animal and might even enjoy a healthy exercise in the process. Moreover, this particular type of “self-moving” vehicle, in contrast to those that called for wind or steam for propulsion, would run on that most abundant and accessible of all resources: willpower. But how to construct such a valuable vehicle? That was the twenty-third of some fifty “useful and entertaining” problems Ozanam identified and addressed in his famous Récréations Mathématiques et Physiques , published in 1696. Ozanam’s book presented a proposed solution from another inventor: another four-wheeled carriage, driven by two people (one to steer, one to power the vehicle by stepping up and down on large treadles connected to the wheels by ropes, pulleys, and gears). It seems that for centuries, the carriage was the model for human-powered vehicles. Various inventors tried their hand at designs, and some were even built. There is a record in a London journal of an attempt in 1774 that went up to six miles an hour. French inventor Jean-Pierre Blanchard (who would later go on to fame in ballooning) built a human-powered carriage that went a dozen miles from Paris to Versailles. An American mechanic named Bolton built a version in 1804 that used mechanical leverage from interlocking gears. Presumably, all these attempts went nowhere because the machines were too large and heavy to be practical. The key insight was to stop trying to build a mechanical carriage, and instead build something more like a mechanical horse. This step was taken by the aforementioned Karl von Drais in the early 1800s. Drais was an aristocrat; he held a position as forest master in Baden that is said to have given him free time to tinker. His first attempts, beginning in 1813, were four-wheeled carriages like their predecessors, and like them failed to gain the support of authorities. But in 1817 (possibly motivated by the aforementioned food crisis and resultant shortage of horses, although this is unclear), he tried again with a new design: a two-wheeled, one-person vehicle that is a recognizable ancestor of the modern bicycle. It was made of wood, with iron tires. He called it the Laufmaschine , or “running machine”; it had no pedals, and ins