The eruption in April 1815 of Mount Tambora, a volcano in what is now Indonesia, was one of the largest in recorded history. A vast plume of dust and ash spread around the world, blocking out the sun and reducing global temperatures. In China the cold weather killed trees, crops and water buffalo. In North America a “dry fog” reddened the sun and there was summer snowfall in New York. Riots and looting broke out in Europe as harvests failed. Food prices soared and tens of thousands of people died from famine and disease. Horses starved or were slaughtered, as the high price of oats forced people to choose whether to feed their animals or themselves.
This last predicament prompted Karl von Drais, a German inventor, to devise a personal-transport machine to replace the horse: a two-wheeled wooden contraption which he called the Laufmaschine (literally, “running machine”). Sitting on a saddle, Drais propelled it by planting his feet on the ground and pushing every few metres, while steering it using a tiller. A demonstration ride, in which he travelled 40 miles in four hours, showed that it was as fast as a trotting horse, and could be powered by its rider without much effort. The tricky part was keeping it balanced while gliding along, which took some practice.
Drais’s invention didn’t replace the horse: the weather returned to normal, leading to a bumper harvest in 1817. Even so, enthusiasts continued to improve on his design. The crucial addition of pedals occurred in France in the 1860s. Other refinements included better brakes, a steel frame, lightweight metal wheels and a chain to drive them. By the late 1880s these elements had been combined into a recognisably modern design: the bicycle.
An invention prompted by the challenges of a long-forgotten global crisis thus ended up spreading around the world and becoming part of everyday life. What innovations might the coronavirus outbreak of 2020 spawn? The pandemic will surely inspire new approaches to online education, say, or package delivery by drone – and, no doubt, some less obvious ideas. Who would have guessed, after all, that a volcano would give rise to the bicycle?•