“You never knew what you were drinking or who you’d wake up with. . . . We wore wishbone diaphragms that weren’t always reliable. There was a woman doctor who handled abortions for our crowd. She would take a vacation at Christmastime to rest up for the rush after New Year’s Eve.”

So wrote Lois Long, a twentysomething correspondent for the New Yorker, the smart-set weekly that debuted in Prohibition-era Manhattan and thrived thanks to nervy, candid tales of the city’s demimonde like hers. The madcap indulgence in New York’s speakeasies and nightclubs in the ’20s that Long chronicled— not just