How the flashbulb changed
the face of urban poverty

IN OCTOBER OF 1887, a New York paper ran a four-line dispatch announcing that two German scientists, Adolf Miethe and Johannes Gaedicke, had hit upon a new technique for taking photographs in low-light conditions. Photographers had tinkered with artificial lighting since the first daguerreotypes were printed in the 1830s, but almost all the solutions to date had produced unsatisfactory results. (Candles and gaslight were useless, obviously.) Early experiments heated a ball of calcium carbonate — the “limelight” that would illuminate theater productions until the dawn of electric light — but limelit photographs suffered from harsh contrasts and ghostly white faces. But Miethe and Gaedicke had come up with a new solution, the New York paper reported, mixing fine magnesium powder with potassium chlorate, creating a much more stable concoction that allowed high-shutter-speed photographs in low-light conditions. The Germans called it Blitzlicht — literally, “flash light.”

Portrait of Jacob Riis, circa 1890s.

It was hardly a front-page story; the vast majority of New Yorkers ignored it altogether. But the idea of flash photography set off a chain of associations in the mind of one reader — a police reporter and amateur photographer who stumbled across the article while having breakfast with his wife in Brooklyn. His name was Jacob Riis.

Then a twenty-eight-year-old Danish immigrant, Riis would ultimately enter the history books as one of the original muckrakers of the late nineteenth century, the man who did more to expose the squalor of tenement life — and inspire a progressive reform movement — than any other figure of the era. But until that breakfast in 1887, Riis’s attempts to shine light on the appalling conditions in the slums of Manhattan had failed to change public opinion in any meaningful way.

A close confidant of then police commissioner Teddy Roosevelt, Riis had been exploring the depths of Five Points and other Manhattan hovels for years. With over half a million people living in only fifteen thousand tenements, sections of Manhattan were the most densely populated places on the planet. Riis was fond of taking late-night walks through the bleak alleyways on his way back home to Brooklyn from the police headquarters on Mulberry Street. “We used to go in the small hours of the morning,” he later recalled, “into the worst tenements to count noses and see if the law against overcrowding was violated, and the sights I saw there gripped my heart until I felt that I must tell of them, or burst, or turn anarchist, or something.”

Appalled by what he had discovered on his expeditions, Riis began writing about the mass tragedy of the tenements for local papers and national magazines such as Scribner’s and Harper’s Weekly. His written accounts of the shame of the cities belonged to a long tradition, dating back at least to Dickens’s horrified visit to New York in 1840. A number of exhaustive surveys of tenement depravity had been published over the years, with titles like “The Report of the Council of Hygiene and Public Health.” An entire genre of “sunshine and shadow” guidebooks to Five Points and its ilk flourished after the Civil War, offering curious visitors tips on exploring the seedy underbelly of big-city life, or at least exploring it vicariously from the safety of their small-town oasis. (The phrase “slumming it” originates with these tourist expeditions.) But despite stylistic differences, these texts shared one attribute: they had almost no effect on improving the actual lived conditions of those slum dwellers.

RIIS HAD LONG SUSPECTED that the problem with tenement reform — and urban poverty initiatives generally — was ultimately a problem of imagination. Unless you walked through the streets of Five Points after midnight, or descended into the dark recesses of interior apartments populated by multiple families at a time, you simply couldn’t imagine the conditions; they were too far removed from the day-to-day experience of most Americans, or at least most voting Americans. And so the political mandate to clean up the cities never quite amassed enough support to overcome the barriers of remote indifference.

Like other chroniclers of urban blight before him, Riis had experimented with illustrations that dramatized the devastating human cost of the tenements. But the line drawings invariably aestheticized the suffering; even the bleakest underground hovel looked almost quaint as an etching. Only photographs seemed to capture the reality with sufficient resolution to change hearts, but whenever Riis experimented with photography, he ran into the same impasse. Almost everything he wanted to photograph involved environments with minimal amounts of light. Indeed, the lack of even indirect sunlight in so many of the tenement flats was part of what made them so objectionable. This was Riis’s great stumbling block: as far as photography was concerned, the most important environments in the city — in fact, some of the most important new living quarters in the world — were literally invisible. They couldn’t be seen.

All of which should explain Jacob Riis’s epiphany at the breakfast table in 1887. Why trifle with line drawings when Blitzlicht could shine light in the darkness?

WITHIN TWO WEEKS of that breakfast discovery, Riis assembled a team of amateur photographers (and a few curious police officers) to set off into the bowels of the darkened city — literally armed with Blitzlicht. (The flash is produced by firing a cartridge of the substance from a revolver.) More than a few denizens of Five Points found the shooting party hard to comprehend. As Riis would later put it: “The spectacle of half a dozen strange men invading a house in the midnight hour armed with big pistols which they shot off recklessly was hardly reassuring, however sugary our speech, and it was not to be wondered at if the tenants bolted through windows and down fire-escapes wherever we went.”

Circa 1887: The cellar of 11 Ludlow Street in New York, where beggars sleep in squalid conditions.
1887: An Italian immigrant rag-picker sits with her baby in a small run-down tenement room on Jersey Street, New York City.

Before long, Riis replaced the revolver with a frying pan. The apparatus seemed more “home- like,” he claimed, and made his subjects feel more comfortable encountering the baffling new technology. (The simple act of being photographed was novelty enough for most of them.) It was still dangerous work; one small explosion in the frying pan nearly blinded Riis, and twice he set fire to his house while experimenting with the flash. But the images that emerged from those urban expeditions would ultimately change history. Using new half-tone printing techniques, Riis published the photographs in his runaway bestseller, How the Other Half Lives, and traveled across the country giving lectures that were accompanied by magic-lantern images of Five Points and its previously invisible poverty. The convention of gathering together in a darkened room and watching illuminated images on a screen would become a ritual of fantasy and wish fulfillment in the twentieth century. But for many Americans, the first images they saw in those environments were ones of squalor and human suffering.

Riis’s books and lectures — and the riveting images they contain — helped create a massive shift in public opinion, and set the stage for one of the great periods of social reform in American history. Within a decade of their publication, Riis’s images built support for the New York State Tenement House Act of 1901, one of the first great reforms of the Progressive Era, which eliminated much of the appalling living conditions that Riis had documented. His work ignited a new tradition of muckraking that would ultimately improve the working conditions of factory floors as well. In a literal sense, illuminating the dark squalor of the tenements changed the map of urban centers around the world.

THE STORY OF BLITZLICHT and Jacob Riis shows us how hummingbird effects work their way into politics and social history. The utility of mixing magnesium and potassium chlorate seems straightforward enough: Blitzlicht meant that human beings could record images in dark environments more accurately than ever before. But that new capability also expanded the space of possibility for other ways of seeing. This is what Riis understood almost immediately. If you could see in the dark, if you could share that vision with strangers around the world thanks to the magic of photography, then the underworld of Five Points could, at long last, be seen in all its tragic reality. The dry, statistical accounts of “The Report of the Council of Hygiene and Public Health” would be replaced with actual human beings sharing physical space of devastating squalor.

Circa 1890: Lodgers in a crowded and squalid tenement, which rented for five cents a spot, Bayard Street, New York City. Twelve men and women slept in a room not thirteen feet either.
1887: A group of men loitering in an alley known as ‘Bandits’ Roost’, situated off Mulberry Street in New York City.

The network of minds that invented flash photography — from the first tinkerers with limelight to Miethe and Gaedicke — had deliberately set out with a clearly defined goal: to build a tool that would allow photographs to be taken in darkness. But like almost every important innovation in human history, that breakthrough created a platform that allowed other innovations in radically different fields.

We like to organize the world into neat categories: photography goes here, politics there. But the history of Blitzlicht reminds us that ideas always travel in networks. They come into being through networks of collaboration, and once unleashed on the world, they set into motion changes that are rarely confined to single disciplines. One century’s attempt to invent flash photography transformed the lives of millions of city dwellers in the next century.

Riis’s vision should also serve as a corrective to the excesses of crude techno-determinism. It was virtually inevitable that someone would invent flash photography in the nineteenth century. (The simple fact that it was invented multiple times shows us that the time was ripe for the idea.) But there was nothing intrinsic to the technology that suggested it be used to illuminate the lives of the very people who could least afford to enjoy it. You could have reasonably predicted that the problem of photographing in low light would be “solved” be 1900. But no one would have predicted that its very first mainstream use would come in the form of a crusade against urban poverty. That twist belongs to Riis alone. The march of technology expands the space of possibility around us, but how we explore that space is up to us.

Excerpted from How We Got to Now: Six Innovations That Made the Modern World, published by Riverhead Books. Copyright © 2014 by Steven Johnson.

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