John Adams dismissed William Franklin (1730-1813) as a ""base-born brat,"" but that oversimplifies the case--or so says author Randall in this somewhat longwinded but engrossing account of the hard time William had with the famous father who sired him out of wedlock. Until his late twenties, Randall explains, ""Billy"" kept very much in Ben's shadow, quietly enduring the older man's indifference and penny-pinching, obedient to every twist and turn of his political maneuvering in Pennsylvania, and content to let him take credit for scientific experiments on which they both worked. (Guess who really went out in the rain to fly that kite?) But then Billy began to establish his own identity: first in Philadelphia's most fashionable circles--where he cut a better figure than his less polished father; then in England--where he studied law, hobnobbed with aristocrats, and found a rich wife; and finally in New Jersey--where he served as royal governor from 1762 to 1776 and won a reputation for hard work, integrity, and extravagant taste. Despite their joint interest in a huge western land-speculation scheme, the imperial crisis of the 1770s revealed how little by then the two men had in common--the one increasingly identified with the cause of American resistance and revolution, the other more and more closely tied to Britain, by career and sentiment, and no longer willing to be bullied. They parted after a bitter quarrel, and until his death a dozen years later Ben passed up no chance for ""a little revenge"" (his phrase, different context)--having the Continental Congress throw Billy in jail, hauling Billy's son Temple off to France, letting Billy's beloved wife die a miserable death in occupied New York, and so on. Despite the loss of many of Billy's papers, Randall manages to be thorough, level-headed, and remarkably even-handed about all this--too thorough, maybe, with excessive doses of political and military background, but mercifully without facile moralizing or psychologizing. (He has previously distinguished himself as an investigative journalist.) Neither one comes out ahead--not the pompous, hypocritical, vindictive old patriot or his foppish, social-climbing, Tory son--and that makes for good reading indeed.