13. The Clock by Christian Marclay, 2010

The Clock is a  24-hour single-channel montage made of thousands of excerpted moments from television and cinema, depicting the passage of clock time. Marclay sifted through an innumerable number of sources to thread each moment together into a seamless functioning timepiece. The Clock vacillates between being a functional timekeeper and distorter, while consistently reminding us of the abstract nature of time itself. 

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