THE DARK ANGEL (374 pp.)Mika WaltariPutnam ($3.75).
Five hundred years ago last week, the Turkish Sultan Mohammed II rolled up his artillery and scaling ladders for one of the most decisive battles ever foughtthe final assault on Christian Constantinople. Inside the battered city, Emperor Constantine XI, last of the 1,000-year-old Byzantine line, delivered a speech to his followers which Historian Edward Gibbon was to call "the funeral oration of the Roman Empire."
Mika Waltari, one of the most successful of practicing historical novelists (The Egyptian, The Wanderer), has taken this most crucial of...