The 1850s have been called the American Renaissance, the decade when distinctive new voices emerged in prose and poetry. The great works were remarkably concentrated: from The Scarlet Letter (1850) to Moby-Dick (1851), to Walden (1854), to Leaves of Grass (1855). In her seminal 1846 essay on American literature in the New York Tribune, Margaret Fuller had called on writers “to develop a genius, wide and full as our rivers, flowery, luxuriant and impassioned as our vast prairies, rooted in strength as the rocks on which the Puritan fathers landed. That such a genius is to rise and work in this hemisphere we are confident; equally so that scarce the first faint streaks of that day’s dawn are yet visible.” That dawn broke just as she vanished into the sea. Emerson was the wellspring of the Renaissance. Walt Whitman, in 1863, predicted that historians would come to acknowledge Emerson as “the actual beginner of the whole procession” of America’s original poets and writers.…