The history of cinema began twice. All art forms are shaped by technological change, but the advent of the talkie in the late 1920s – only a few decades after the first silent films – did not so much develop the medium as kill it and replace it with something new. So abrupt was the change that the strange visual operas of cinema’s earliest years became imbued with a certain innocence, now almost impossible to replicate. To this day, silent film has an aura of mystery, a quality that cultural critic Peter Conrad addresses in his erudite new book.