Spring 2013. I am standing in front of Marcel Duchamp’s collaborative artwork of 1916, With Hidden Noise (À bruit secret), protected in its glazed case, at the Barbican Gallery, London, and wishing not just that I could put myself closer to this puzzling apparatus, but that I could pick it up and shake it: that I could activate the secret sound within it. Between two small, nearly square metal plates bearing incomplete text phrases and held in place by four long machine screws: a ball of twine; inside the ball of twine: an unknown object, placed there at Duchamp’s invitation by the work’s first owner, Walter Arensberg (Fig. 1). “Unrelentingly strange” in the words of one commentator (Harris 2013: 23), the work eludes my intellect in its refusal to explain itself, in those deliberately stalled inscriptions that both announce and withdraw some solution to an enigma. In a game of transatlantic tag, here it is in London when it normally lives in Philadelphia, paraphrasing Duchamp’s own peripatetic journeys between Old and New Worlds – like that other burrowing object in a stringed machine, a shuttle. It is as though the Philadelphia Museum of Art, home to a major display of Duchamp’s work as well as to Arensberg’s art collection, had kept hold of one end of its reel of string and will eventually wind it back, rehearsing loss and restitution, silence and exclamation, like every collector who lets go then reclaims a precious possession. Fort! Da!