Translator, literary critic, magazine editor, and biographer, William Henry Channing is numbered (in Ralph Waldo Emerson's phrase) among the "young men with knives in their brains" who constituted the first generation of New England Transcendentalists. He was born into a stable, prominent family--his uncle Dr. William Ellery Channing was arguably the most influential Unitarian minister of his day--yet his intellectual and spiritual wanderlust began early. He attended Harvard College, graduating with the famous class of 1829, and went on to Harvard's Divinity School. At Cambridge he became imbued with German romanticism, filtered through the writings of Samuel Taylor Coleridge and Thomas Carlyle; like others of the Transcendental circle, he read prodigiously and widely, in philosophy and world religions as well as in belles lettres. His eclectic education, combined with an apparently constitutional inability to stay put, made him a wide-ranging critic of literature and culture whose work suffered from...