THE MAN or THE RENAISSANCERalph RoederViking ($3.50).
History, defined politely as "the formal record of the past,'' is really organized gossip; but among the historians who retail it there are generally more bores than raconteurs. Historian Ralph Roeder is no bore. His crowded subject, the climax of the Italian Renaissance (1494-1530), could easily trip and entangle a pedestrian fact-plodder, but Author Roeder slips adroitly through its thickets, his eye always on one of his relay of four guides (Savonarola, Machiavelli, Castiglione, Aretino). Not a portrait of some composite Renaissance man but...