Sudhir Venkatesh's "Floating City," and More Illustration by John Gall FLOATING CITY A Rogue Sociologist Lost and Found in New York's Underground Economy By Sudhir Venkatesh Penguin Press, $27.95. When Venkatesh, a sociology professor, presented his proposal to study drug dealers and sex workers to a Columbia University research review board, his colleagues dismissed the project as mere "journalism." Undeterred, he moved forward, winning the trust of professional lawbreakers, much as he did in "Gang Leader for a Day." He found that in contrast to Chicago, the setting of his previous book, where your neighborhood was your fate, people "float" in New York, pursuing opportunity across town and across race and class lines. The self-described "rogue sociologist" shadows Shine, a Harlem drug dealer who is dropping his uptown crack clientele for a richer, whiter cocaine customer base downtown, and Analise, a Gramercy Park socialite who runs a high-end prostitution ring. But for all his deep reporting, Venkatesh offers only thin sociology - just a few perfunctory nods to social theories of gentrification and the "global city." Even when New York madams tell him that large numbers of middle-class women are surprisingly open to doing sex work to "supplement poorly paying straight jobs," he neglects to put this remarkable fact into the context of feminist debates over exploitation and empowerment, or demographers" charting of the demise of New York's middle class. Perhaps his Columbia colleagues were right: "Floating City" is just journalism. But in offering vivid portraits of sources with so much to lose, it is journalism of a very high order. SMART CITIES Big Data, Civic Hackers, and the Quest for a New Utopia By Anthony M. Townsend Norton, $28.95. It's alive! Your city, that is. And it's watching you. This can be a boon, as in Istanbul, where IBM recently revamped bus routes based on where passengers" mobile phones revealed them to be going, but not so great in Chongqing, where video cameras will soon record every street corner with the help of Cisco. Guiding us through the nexus of urbanization and digital technology is Townsend, the rare technologist who is in the know without being in the tank. He turns a skeptical eye toward the giant companies salivating over "the $100 billion jackpot" that will be spent to connect cities with information technology. He repeatedly reminds us of the 1939 New York World's Fair, where a General Motors-sponsored "Futurama" exhibit sold the country on a vision of expressways and suburbs that was good for G.M. but bad for America. Fool us twice, shame on us, Townsend suggests. Rather than again turning over our collective future to the "paternalistic philosophy" of multinational corporations, "Smart Cities" endorses "civic hackers" who create public-interest apps tailored to their hometowns. Map Kibera, for example, allows Nairobi slum dwellers to keep a corrupt and ineffectual government honest by crowdsourcing updates on the progress of public infrastructure projects. Less a to-do list than a framework and a sensibility, "Smart Cities" is a timely and necessary guide to this age of the Franken-city. THE URBAN BESTIARY Encountering the Everyday Wild By Lyanda Lynn Haupt Little, Brown, $27. In this curious work, a naturalist attempts to bring the bestiary, a medieval illustrated compendium of animal lore and knowledge, into our modern age. Part tracking guide, part mythology sourcebook, part treatise on the place of humans in nature, "The Urban Bestiary" is a primer for a civilization that can't keep from intruding on pristine wilderness. Being mindful of nature, Haupt exhorts, can increase our connection to it even when we're in our urban homes. Take a good look at the squirrels out your window, she advises, and you'll soon realize they're your squirrels; squirrel couples generally keep to just a half-acre of land. And beware the slanders against our most common animal neighbors. Rats, Haupt notes, "spend far more time cleaning and preening than humans do." As for "rats with wings," Haupt reminds us that pigeons are taxonomically doves and make great pets: "Hand-raised pigeons are delightfully tame, cuddly, gentle and have the endearing habit of settling all warm and feathery under the hair at the base of your neck." How sympathetic readers will be to this "Seattle eco-hippie," a vegetarian who sleeps in a tent in the yard every summer, will vary, as will their interest in reading what is, ultimately, a reference book. But "The Urban Bestiary" will make even the most hard-boiled urbanite look at the pigeon on the telephone wire as more than just a potential dry-cleaning bill. UNFATHOMABLE CITY A New Orleans Atlas By Rebecca Solnit and Rebecca Snedeker University of California, cloth, $49.95; paper, $29.95. My first landlord in New Orleans, a Tennessee native who had lived in New York and Washington, told me that after a few years in the financial and political capitals, he understood them. But after a decade in this sweltering city, with its 18th-century fusion cuisine, misplaced Massapequa-on-the-Mississippi accent and transvestite rap divas, he was "still just peeling back the layers." In the second volume of her planned trilogy of deliciously eccentric atlases, Solnit, the Left Coast polymath, amasses a team led by Snedeker, a New Orleans filmmaker, to plumb the Crescent City's admittedly "unfathomable" depths. As cultured New Orleanians know (or at least pretend to), the word essay comes from the French essayer (to attempt); the book's most rewarding essays are not its most successful attempts but its most audacious. Is it a single civic psychosis that led Louisiana to construct the world's largest pumping station and the nation's largest prison in costly, fruitless attempts to solve New Orleans's notorious flooding and crime problems? Do local cravings for raw oysters and raunchy sex share a root? Maybe. Regardless, this objet d'art is as infectious as a second line, an urban art form that the scholar-parader Joel (Heavy D) Dinerstein points out is named for its audience participants instead of its leaders. With "Unfathomable City," Solnit and Snedeker have produced an idiosyncratic, luminous tribute to the greatest human creation defined by its audience participants: the city itself. Daniel Brook's "A History of Future Cities" was published last year.