Rather grandly housed in a less-than-glamorous Manhattan neighborhood, the American Academy of Arts and Letters tends to keep a low profile. Indeed, most people have probably never heard of the institution, which hands out awards and grants and convenes once a year for a celebrity-intensive blowout. Yet this all-American equivalent of the Academie Française has just turned 100, occasioning this chronicle by an eminent round robin of academicians. R.W.B. Lewis covers the initial decade, during which William James declined his nomination on the grounds that his little brother Henry had been elected first. Norman Mailer recalls the momentary entente between the Kennedy White House and the arts community, while architecture critic Ada Louise Huxtable documents the Academy"s semicomatose state during the early 1980s. A Century of Arts & Letters is, on one hand, a kind of anthropological study, which tells us a great deal about the roosting patterns of artistically-inclined Homo sapiens. Yet it also tracks the slow incursion of modernism into the academy, which has finally embraced it and made a little room, even, for the postmodern barbarians at the gate.