A center of mechanical marvels, Alexandria boasted automatic doors and hydraulic lifts, hidden treadmills and coin-operated machines. With invisible wires, siphons, pulleys, and magnets the Ptolemies could work miracles. Fires erupted and died down; lights flickered from statues’ eyes; trumpets blared spontaneously. For the early procession, the city’s ingenious metalworkers outdid themselves: A fifteen-foot-tall statue in a yellow spangled tunic floated through the streets. She rose to her full height, poured offerings of milk, then magically reseated herself, enthralling the crowds.