Book excerpt: This novel of Ben Franklin, Isaac Newton, and a demonic Louis XIV is “eminently worthwhile reading for both fantasy and alternate-history lovers” (Booklist). In 1681, in an England somewhat like our England . . . the great alchemist Sir Isaac Newton makes the remarkable discovery of a substance he calls philosopher’s mercury, with which one can manipulate the four essential elements of the universe: earth, water, air, and fire. In the opulent court of Britain’s greatest enemy, the ancient King Louis XIV, his life alchemically and indefinitely prolonged, employs treacherous means to obtain the prize that will grant him dominion over the entire continent. Meanwhile, his brilliant and beautiful mistress, Adrienne de Mornay de Montchevreuil, secretly pursues a mathematical method to prevent his takeover. And in another corner of the world, the young printer’s apprentice and aspiring alchemist Ben Franklin is plagued by a demon and flees to England seeking the aid of his hero: Newton. But Franklin will discover that Newton has demons of his own . . . A wondrously dark and richly imagined alternate history, Greg Keyes’s Newton’s Cannon is the first book in his extraordinary Age of Unreason series—a magnificent journey to a past that never was in a world where magic is a science and the greatest minds must conspire to prevent an end to all things.