MANHATTAN, WHEN I WAS YOUNG

MANHATTAN, WHEN I WAS YOUNG Mary Cantwell (Houghton Mifflin, $21.95) In her memoir of the postwar '50s and '60s in magical Manhattan, Cantwell, a writer and magazine editor, conjures up a nostalgic era before the standard of living was seriously affected by inflation. Those were the days when college grads could eke out a meager existence in publishing and still live modestly but happily. Cantwell hinges her candid account on a series of apartments she inhabited between graduating from college, working for various magazines, marrying a rising star in the publishing business, having children, and finally divorcing. Her memoir is absorbing and effervescent; the apartments themselves are so well described that they end up becoming vivid minor characters. One of the smaller, dingier ones ''faced an airshaft, and when it snowed the flakes drifted into the warm air toward the bottom of the shaft and then rose, so that looking out a window during a blizzard was like looking into a popcorn machine.''

Throughout, Cantwell refers to her husband as B. and cannot bear to speak his name (she suffered terribly when their marriage broke up). This is a pity, for it distances the reader from a very important person in what is otherwise a poignant pastiche of urban life in a bygone time. A-