Concentrating on the 1849-1855 transformation of hack-journalist Whitman into the inspired Leaves oS' Grass poet, Zweig (Comp. Lit., Queens College) emphasizes the intent and craft behind this apparent eruption of native genius; at the same time, less originally, he stresses the poetry as ""a dream of personal expansion,"" reflecting both mid-19th-century America and Whitman's insistence on the total correspondence between his life and his work. After a very brief consideration of the writer's early years, seeing his family history in terms of ""the Victorian marriage myth"" as well as Freudian psychology, Zweig concentrates--not very differently than did Justin Kaplan's 1980 biography--on the popular passions of mid-century America that vibrated through the 30-ish Whitman: theater, grand opera, the romance of democracy, phrenology (with its body/spirit connections), urban bustle, American optimism about change. He closely examines the journalism and early-1850s notebooks of ""a man awakening from a lifelong sleep""--tracing themes (nature, art, death) and heralding verbal development. (""We see the sweeping, hard-edged language, so different from the pudgy journalistic prose he was still capable of."") He makes it clear that the poet wasn't the intellectual hermit he sometimes pretended to be: ""Not only did Whitman read, he scavenged, paraphrased, and pastiched."" (Like Kaplan, Zweig suggests an important Carlyle influence.) As for Whitman's homosexuality, Zweig sees him as ""fairly chaste"" in practice, ""intransitive"" and mystical in eroticism--molding the resources of his poetry to express ""sensory expansion, physical ecstasy."" And finally Zweig turns to the poetry itself--focusing on ""Song of Myself"" (an ""engine of self-making""), noting the uneven quality of the late-1850s work (with guilt and inhibitions re sexuality). . . and ending with Whitman's 1860s shift from ""verbal adventurer"" to ""prophet and man of wisdom."" Somewhat repetitious in format, and not completely persuasive in its interpretive reliance on dualities (""the infantile visionary was also a crafty poet"")--but a strong, occasionally eloquent analysis/appreciation: for readers who want a densely critical approach rather than Kaplan's low-key narrative.