This is from Iain Sinclair’s London Orbital:

“I spent Saturday afternoon, in the rain, observing a pair of middle-aged mudlarks, up to the elbows in liquid sewage. One of them dragged an old tin bath out into the river, at low tide. The other worked with a sieve like a grizzled prospector, Walter Huston in The Treasure of the Sierra Madre. They spent hours laboriously shifting shit, hoping for the odd ring or coin. And I stuck with them, watching. This was about as far as you could travel from John Prescott. He couldn’t, even it it were explained to him, find anywhere to place such humans. Demographically, they had pulled it off. They didn’t register.”