The music of ancient Greece, unheard for thousands of years, is being brought back to life by Armand D'Angour, a musician and tutor in classics at Oxford University. He describes what his research is discovering. "Suppose that 2,500 years from now all that survived of the Beatles songs were a few of the lyrics, and all that remained of Mozart and Verdi's operas were the words and not the music. Imagine if we could then reconstruct the music, rediscover the instruments that played them, and hear the words once again in their proper setting, how exciting that would be. This...