Limited LP. Includes download code. Both sides open inside Tower Bridge. Side A begins in the north bascule chamber during a lift in 2013, side B in the south chamber in 2017, and the record closes on the electric motors of the bridge's machine room. Between those returns to the machine, everything gets further away and quieter.

What lies downriver is dated and located rather than evoked. Allhallows Marshes on a summer afternoon in 2011. The tidal landscape of Maplin Sands in 2012. Wind striking the flagpoles of Albert Basin in the Docklands, also 2012. Allhallows again at night in 2018, marsh frogs going over the top of passing cargo ships.

And the siren of the Coryton Refinery, recorded in 2010. The plant shut down in 2012 and was demolished. That track is the argument of the whole project in one object: Ian Rawes began the London Sound Survey in 2008 because he sensed the city's rate of change was quickening and nobody was keeping account of how it sounded. Urban sound goes extinct imperceptibly. There is no last-ever moment and no announcement, just a thing that stops being made — except here, where it was recorded two years before it stopped.

The Survey went online in 2009 and now holds over 2,000 modern recordings alongside a large body of historical sound material. Rachel Lichtenstein, author of Estuary: out from London to the sea, called this collection an audio mosaic reflecting an extraordinary landscape, and mosaic is the right word: eight pieces set beside one another across eight years, not a journey taken in one go.