Obscene, libidinous, loathsome, lascivious. Those were just some of the ways critics described the nineteenth-century weeklies that covered and publicized New York City's extensive sexual underworld. Publications like the Flash and the Whip --distinguished by a captivating brew of lowbrow humor and titillating gossip about prostitutes, theater denizens, and sporting events--were not the sort generally bound in leather for future reference, and despite...