Chord: Conrad Shawcross’ huge mechanical sculpture is hidden in the disused underground Kingsway Tram station in the belly of Holborn for those brave enough to venture in… Vanessa and I visited it last week.

Two huge, intricate pieces of industrial machinery rotate as if by clockwork, inching apart from each other at a glacial pace. They patiently weave a rope from over one hundred spools of brightly coloured thread, and by the time the month-long exhibition finishes, they will span the entire accessible length of the tunnel.

It’s on until 8th November, and is free! Go http://www.measure.org.uk/measurenews.html