Nelly Bly made history in 1887 when she posed as a mental patient in order to investigate the treatment of the insane. Working for Joseph Pulitzer, then head of the New York World, Bly was not only one of the first women journalists, she was also the inventor of undercover investigative reporting.

Since then, muckraking of all stripes has enjoyed a special place in American journalism. From Ida Tarbell’s expose of Standard Oil’s

monopoly and Upton Sinclair’s harrowing portrait of the Chicago meatpacking industry to Studs Terkel’s oral histories and Susan Faludi’s Pulitzer Prize-winning work on the leveraged buyout of Safeway, the ideal of progressive reporting – of documentation that would lead to positive social change – has been a guiding principle of American journalism.

Barbara Ehrenreich’s Nickel and Dimed: On (not) Getting By in America is a rich addition to this already rich tradition. In 1998, Ehrenreich’s editor at Harper’s sent her out on a fact-finding mission: Her job was to pose as a low-wage worker, and her mission was to discover how – or whether – someone can live on the low hourly wages that are commonly paid to “unskilled” workers.

Undertaking her investigation in the wake of welfare reform and at the height of America’s economic boom, Ehrenreich was especially interested in how the roughly four million women about to be forced onto the labor market would cope: What work would they do? What would they earn? And how would they make ends meet? Armed with a laptop, a Rent-a-Wreck, $1000 in seed money, and her health, Ehrenreich ran the experiment three times in three locales, starting by waiting tables in Key West, moving on to cleaning houses in Portland, Maine, and ending with a stint in women’s clothing at a Minneapolis Wal-Mart.

Nickel and Dimed is divided into three sections, one for each place, and it is written in a riveting combination of personal narrative and economic analysis. Each section describes in detail Ehrenreich’s difficult and frustrating searches for decent jobs and passable housing; the steep expense of food and gas; the physical and emotional exhaustion of repetitive, demanding hourly work; the degradations of the urine tests and personality tests that form a standard part of the application process for much low-wage work, and the bonds she forms with her fellow workers as she moves from one job to the next.

What begins as a relatively simple economic experiment – can you get food, shelter and clothing for one on a Wal-Mart-level wage? – thus evolves into much, much more. Nickel and Dimed is as powerful a sociological statement as it is an economic one; Ehrenreich has as much to say about the culture of the working poor and the psychology of low-wage labor as she does about the gruesome math problem posed by the need to live on $6 or $7 an hour.

Along the way, Ehrenreich offers spot analyses of everything from the

demographics of low-wage work (which is increasingly becoming the territory of non-white, non-English speaking people) to the techniques of professional maid services (which do more to create the appearance of cleanliness than to clean, and which often require scrubbing to be done on one’s knees) to the decreasing availability of low-income housing (which forces more and more workers to live in overpriced hotels, in shelters or even in their cars).

Part memoir, part manifesto, Nickel and Dimed challenges us to drop the complacent belief that jobs eliminate poverty. Ehrenreich conducted her experiment with a car and enough start-up money to pay housing deposits – assets that many low-wage workers don’t have. She worked more than full time, often juggling two jobs and sometimes working seven days a week. And even so she went hungry, struggled continually to make her rent, felt her strength and her sense of self seep away, and was only saved from certain destitution by the journalist’s prerogative to terminate the experiment. We like to say that employment is the antidote to poverty, Ehrenreich notes. But it is just not that simple. The truth, as she so devastatingly shows, is that cheap and plentiful jobs just make it easier not to know how extensive or how grinding poverty in America really is.

Nickel and Dimed is finally a devastating picture of an America that is

not what it seems to be. The kind of commonplace, continuous hardship Ehrenreich experiences firsthand is completely invisible to a system that calculates the poverty level by the price of food – which is fairly inflation-proof – rather than by the cost of rent, which is market-driven and which has skyrocketed as more and more tenements have been turned into condos, housing developments, golf courses and the like. The official poverty rate may have remained steady at a respectable 13% for years, Ehrenreich notes. But even so, 20% of all homeless are employed in either full- or part-time jobs.

The impulse to reveal the human costs of decadence was neatly answered over a century ago by Jacob Riis’ powerfully illustrated 1890 study of New York City slums, How the Other Half Lives. Riis combined uncompromisingly graphic photographs of urban squalor with hard-hitting expository prose, and he did so at the height of the Gilded Age, when entrepreneurs such as Henry Clay Frick, Andrew Carnegie and John D. Rockefeller were making obscene amounts of money in coal, steel, and oil, and when famously wealthy families such as the Astors and Vanderbilts were flaunting their lavish lifestyles.

Nickel and Dimed is a kind of How the Other Half Lives for contemporary America. Ehrenreich did the research for Nickel and Dimed during a period of unprecedented economic growth, and she aimed, like Riis, to outline in unforgettable terms the struggles of those who were not making millions on Wall Street, but were instead doing the drudgery – the serving, the scouring and the selling – that keeps an affluent America up and running. When Riis was writing, the notion of “the other half” was a generous metaphor: Riis claimed that 1% of Americans owned 99% of the wealth; more conservative estimates suggest that 10% of Americans owned 90% of the wealth. But today, the metaphor has become an accurate description. Despite our enlightened perspectives and our social services, 60% of American workers still earn less than the official living wage of $14/hour; 30% work for less than $8/hour. The more things change, it seems, the more they stay the same.