Lighting the way
A Short Bright Flash: Augustin Fresnel and the Birth of the Modern Lighthouse by Theresa Levitt. New York: W. W. Norton & Co., 2013, 288 pp.
Jody A. Roberts
In A Short Bright Flash: Augustin Fresnel and the Birth of the Modern Lighthouse, Theresa Levitt wastes little time in revealing just how bad things were for sailors in the 19th century. She begins with the grisly tale of la Méduse, a ship run aground off the coast of West Africa in 1817 and the abandonment, murder, and cannibalism that followed. Of the nearly 150 individuals who took refuge on a makeshift raft adrift in the Atlantic Ocean, only 15 survived the 15-day ordeal before being rescued. Not every shipwreck ended so dramatically, but with hundreds of boats lost each year (the British insurer Lloyd’s of London put the number at 362 in 1816 alone), the event and its awful ending struck a sensitive chord with an anxious public.
Thus, the scene was set for Fresnel’s invention of his eponymous lens, which proved to be a miraculous feat of mathematics, optics, and engineering. Lighthouse engineering held that a brighter light could be generated only by increasing the quantity of light available (more oil, more wicks) and reflecting that light with larger reflectors. Fresnel, a French physicist and engineer, challenged this approach by first arguing that the amount of light lost in the system needed just as much attention as the amount of light produced and reflected. That is, by examining the behavior of light and understanding how to maximize it, it would be possible to create a lamp that not only shone brighter and farther, but theoretically could do so with less oil. In turning this theory into reality, Fresnel challenged not only the status quo in lighthouse operations; he grounded his approach within the contemporaneous debates then raging within scientific circles about the nature of light.
Fresnel’s suggestion that light possessed wave-like properties kept him firmly on the outside of received wisdom. He was not alone in his approach to light, but his careful studies and experiments demonstrating wave properties of light before the scientific elite of France made him a hero of the scientific avant-garde challenging the entrenched authorities in the debates about the nature of light. More importantly for Fresnel, the experiments demonstrated the theoretical possibility of his approach to new lighthouse technologies: the secret was in the lens, not the light source.
Fresnel’s design, based as it was on mathematical precision, required massive lenses carefully constructed through the ordering and placement of each individual piece of glass. Defects in the glass or parts placed at a wrong angle would lead to a scattering of the light and a loss of the focusing power that made the lens work. The craftsmanship required for lens construction resulted not only from the nature of the precision needed for the glass but also from the effort required to cut glass of this size. The introduction of steam power meant lathes could operate faster, yielding more lenses and more lighthouses equipped with the Fresnel system.
Once made, these lenses needed to be installed—a feat that required transport of delicate glass parts to remote ends of the country (and eventually the world), installing them in giant towers often placed precariously on a nearly inaccessible outcropping of rocks, and into a room scores of feet in the air. And yet somehow it all worked.
New class of engineers
Levitt presents Augustin Fresnel as an unlikely hero of this era. But Fresnel was a product of a radical shift in education happening in France in the 19th century. The creation of the new elite engineering schools in France made possible this rise from obscurity to national hero. Indeed, Fresnel took part in a larger national experiment that not only focused on technical training; it also tied engineering to governance and political power. Engineering for the state was also engineering of the state, a fact embodied in the perhaps even more unlikely rise of a young ballistics and artillery engineer named Napoleon Bonaparte to ultimate power in France (and much of Europe).
France deployed its engineers across the country in the service of the state— building infrastructure, surveying, training its military. Fresnel was one of this new class emerging in France (and indeed spent most of his time overseeing the construction of roads and other infrastructure, a job he absolutely despised). Being an engineer meant the state supported you, but it also meant you supported the state. As Fresnel’s new system found its way across the country, the light stood as a glowing example of French engineering and not just the genius of Fresnel. Indeed, installation of his lighting system at expositions of engineering in Paris (following Fresnel’s early death attributed to consumption) was taken to be an example of the power of France and its new engineers.
Lighthouses and Fresnel’s lens meant more than just safety for sailors; they constituted physical symbols of the expansion of commerce. The loss of a ship of happy travelers would have been tragic indeed. But the loss of a commercial fleet was expensive and disruptive to the national economy. Lighting the coast did not happen all at once; the lighthouse commission in France set priorities based on safety and strategic importance of the ports. Once the coast was lit (a massive and thorough undertaking by the French government, overseen by its engineers), lighthouses with Fresnel lenses began appearing in more remote—but equally strategic— locations: Corsica, Algiers, and Gibraltar among them. Lighthouses equipped with Fresnel lenses became part of commercial infrastructure.
Though Levitt spends much time documenting the resistance by some people and groups in the United States, when the lenses did arrive, they, too, were prioritized by their commercial importance. When gold was found in California at the close of the 1840s, it took a mere two years for San Francisco to boast new lighthouses using Fresnel lenses—an amazing feat given the distance from the center of manufacturing in France and the demand for lenses at the time.
In a telling tale of the strategic importance of the lighthouses and the power of these lenses, Levitt documents the efforts taken by the Confederacy at the start of the U.S. Civil War to impose a blackout along the southern coast. Remarkable, however, is the unbelievable care taken by state authorities (and even raiding parties) at the onset of war to carefully dismantle the lenses for safekeeping in hidden locations. Although some lighthouses saw their hardware simply smashed into a thousand unusable bits, much of the hardware remained undamaged (if far from its original location) and found its way back to Federal authorities at the end of the war.
Lessons for today
In her telling of the historical emergence and evolution of the modern lighthouse, Levitt digs deep into the technical construction of the first lenses and the methodical placement of lamps as they began to dot the coasts of empires big and small. But for all of the detailed historical description that populates her careful depiction of the Fresnel lens and its production in the 19th century, the book lacks a compelling narrative or even larger context within which this feat can be fully appreciated. Despite that absence (or perhaps in lieu of Levitt’s efforts), it is possible to draw some ideas from the book that may compel further conversation.
To fully understand what happened as these events unfolded and why it was so amazing, it is necessary to understand the scientific debates and technological challenges, as well as the pressing social and political and economic needs, of the time. To focus on any one of these elements without the others is to miss the much bigger picture this story is trying to tell.
The lens was just one part of a larger system; and in this regard the lighthouse is not a singular object, but part of a larger infrastructure of the state. When viewed from this perspective, it is easier to understand why France and the United States took such different approaches to the installation of these new technologies. In fact, it is not only easier, but essential for taking one of the main points from this book. In the largely centralized and technocratic state of France, the institutionalization of new lighthouses equipped with Fresnel lenses followed a “rational plan.” In the United States, factors such as the role of open markets, the status of scientists and engineers, and the reluctance to use (or opposition to) federal funding of large state projects left efforts to update the then-current system stuck in a bureaucratic trap and with inadequate funding.
Sound familiar? It should—and that is one of the main lessons of this book. Just think about the debates in the United States today over nuclear power, funding of research, and the role of the university versus the corporation as engines of innovation. The landscape today did not suddenly appear. Treating this terrain of comingled science, technology, politics, and cultural identity with more attention could go a long way toward helping policymakers and stakeholders to appreciate the unique character of these systems. And a better understanding of how these systems came to be can go a long way toward helping us to create alternative possibilities for moving forward.
In all, A Short Bright Flash is a wonderful reminder of just how much effort goes into the construction of the nation’s largely invisible (and crumbling) infrastructure. Perhaps more discussions of this sort might yield a deeper appreciation for the efforts that need to be made to build and maintain an infrastructure for the 21st century.
Jody A. Roberts (jroberts@chem heritage.org) is director of the Center for Contemporary History and Policy at the Chemical Heritage Foundation in Philadelphia, Pennsylvania.