Sea travel in the early 1800s was a risky proposition. Lighthouses had been around since at least the third century B.C., but they were too few in number and insufficiently bright to be of much use when the weather turned treacherous. With sea trade on the rise, the number of shipwrecks remained consistently high; the insurer Lloyd’s of London tallied 362 ships wrecked on rocky coastlines in 1816 alone.
Part of the problem was that the accepted scientific theories of light held that light traveled in particles, and the idea that it traveled in waves was still an outsider view. An engineer named Augustin-Jean Fresnel was one such outsider. Assigned by the government to menial road-building supervision, he dedicated his leisure time to solving one of the mysteries of light that Isaac Newton hadn’t been able to crack. Diffraction — the spreading out of light after it travels through a narrow gap — was one of the unsolved mysteries of the particle theory. Fresnel’s revolutionary ideas about considering the motion of light as a wave enabled him to design a system of lenses that would amplify lighthouse beams many times over.
As Theresa Levitt’s fascinating book describes it, however, Fresnel’s journey from scientific outsider to innovator of lighthouse technology wasn’t exactly smooth sailing. Mahatma Gandhi, describing his attempts to bring about change, said, “First they ignore you, then they laugh at you, then they fight you, then you win,” and Fresnel’s innovative research resulted in a fast transition to that third stage. Much as they are today, politics and personal reputations were built on maintaining the status quo, and Fresnel’s ideas faced an uphill climb against the entrenched ideas of the time.
“A Short Bright Flash” carries the story well past Fresnel’s death at age 39, as the obstacles to his ideas becoming reality lasted well beyond his passing. His brother Leonor was smart enough to oversee the continuing research into the ideas, but he also excelled in an area his brother struggled with: Leonor was charismatic. With Augustin’s innovations in hand, Leonor through the force of his personality drove efforts to navigate relationships with politicians, glassmakers and eventually even other nations.
Levitt’s writing captures the mix of scientific rigor and cultural shifts in a way that mirrors the sea voyages of the day — a journey fraught with uncertainty, but in the end, guided to success by Fresnel’s lighthouse lenses.
Matthew Tiffany is a writer and clinician. He blogs at http://condalmo.com