The author has chosen an access to the essential Byron and his circle -- the poet's finances -- usually disdained by biographers. Moore's research has produced a wealth of long-buried material, particularly the conscientious archives of Byron's house steward, his ""secretary,"" Lega-Zambelli, which illuminate Byron's Italian sojourn. Byron had frantically awaited the removal from England -- from the wild tangle of estate finances, his disastrous marriage, the debts of his youth. Byron's ""spiritual claustrophobia,"" aggravated by his financial situation, ""gave to everything he did a feeling of transience, of unreality. . . he meandered into situations."" But in Italy his youthful libertinism subsided and a stronger need for a self-abnegating independence took its place (the author marks the coincidence of relatively thrifty living with his affair with Teresa Guiccioli). Throughout the narrative -- soundings of Byron's career from childhood to his death -- there are shrewd defenses of the traditionally maligned (Byron's mother and Teresa e.g.); a back-of-the-hand for those who, Moore convinces us, deserve it (the nit Clare, Trelawney, Byron's father who had questionable intimacies with his sister) and some casual but mind-boggling suggestings about other relationships. Moore skims through the archives and comes up with a multitude of matter, stylish and vital.