[Here’s a link to other forays around my map.]

This was, perhaps, a grid square that only a nerd like me could love. More than half of it was blue, an incongruous representation of the muddy, mildly intimidating industrial estuary sprawling out before me. Behind me the entire remainder of my grid square was fenced off, either by a large police shooting range, a power line terminal tower where the cables tunnel deep beneath the estuary, a huge complex of dry mortar silos, and a specialist firearms training centre for the police which is effectively a small town, with mock roads, houses, shops, a bank, a pub, a nightclub, a football stadium, a life-size section of a plane and train and underground stations with full-size carriages. (This, incidentally, brought back fond memories of getting a day’s pay in the Territorial Army to don ‘civvy’ clothes and cheerfully lob half bricks and milk bottles at massed ranks of policemen in riot gear. All fun and larks until they mounted their response charge at us!)

Today’s grid square was thus reduced to nothing more than the grassy shoreline footpath along the flood defence embankment. The footpath, and whatever foreshore the estuary revealed at low tide. And that was the reason why I had checked the day’s tide timetable and arrived here (past a storage yard of ship’s anchors –10 foot tall and tonnes galore) a couple of hours before low tide. I was here to go ‘Mudlarking’.

A mudlark is someone who scavenges in river mud for items of value, a term used especially to describe those who scavenged this way in London during the late 18th and 19th centuries. Mudlarks would search the muddy shores of the River Thames at low tide for anything that could be sold; and sometimes, when occasion arose, pilfering from river traffic. The income generated was seldom more than meagre; but mudlarks had a degree of independence, since (subject to tides) the hours they worked were entirely at their own discretion and they also kept everything they made as a result of their own labour. 

I have recently devoured a fabulous book about Mudlarking (and the author’s Instagram posts). I found myself fascinated by the prospects of magical finds, Roman roofing, Tudor shoes, messages in bottles, and mudlarking shed envy. This all lured me to the foreshore of the River Thames, a spooky, mysterious and temporary beach that appears and disappears twice a day, as the river — milky grey, like old, cold tea — rises and falls with the powerful tides. The constant churn brings to the surface objects that have been preserved in the mud. For those with the eyes to see, this 100-mile stretch is “England’s longest archaeological landscape.” You can find stuff you don’t see in a museum, and you can see things for yourself, those tooth marks on a clay pipe, a fingerprint on a roof tile, and you can make up any story you want. Nobody really knows how it ended up in the river.

I donned wellies and waterproof trousers, climbed up and over the graffiti-ed embankment wall, and dropped down onto the foreshore. This far from London the estuary at low tide is a lethal gloop of deep, sloppy mud. Stinking, grey, and cloying. I had to settle for making my way along the line where rock and mud meet, picking my way gingerly over slippery Bladder wrack. This brown seaweed lives in the mid shore and looks a bit like bubble wrap with the distinctive air bladders that give it its name. Bladder wrack was once used as a source of iodine to treat goitres. Nowadays, you’re more likely to find it in your anti-ageing cream as research has found that it has anti-ageing properties. Bladder wrack has round air bladders which allow the seaweed to float upright underwater, this helps them exchange gases and absorb nutrients when submerged. It forms dense beds on the mid shore, often together with Egg Wrack. It provides a shelter for many creatures and is a food source for others, including the Flat periwinkle.

Yet I saw not a single living creature amongst it all. There were a few seagulls bobbing on the water, and some feral ponies grazing on the embankment. But only a few old oyster shells gleamed pearly white amongst the grey mud and brown seaweed. Over the last 200 years the oyster population has decreased by 95% due to historic overfishing and the oysters’ recovery has also been hindered by habitat loss, pollution and the introduction of diseases. Yet they are on the increase again, and things are improving from the low-point of 1957 when the Natural History Museum declared the Thames biologically dead. News reports from that era describe it as a vast, foul-smelling drain.

I was secretly hoping to find Roman treasure within minutes of beginning my search. Instead I found seagull footprints, a rusty chair frame and plastic galore, including a label saying ‘BAG IT AND BIN IT, DON’T FLUSH IT’. I found a 1980s milk bottle with ‘PLEASE RETURN BOTTLE’ embossed on the glass. All interesting enough, but where was that jewel-encrusted sword when you needed it? Truth be told, my patience began to wane within about 20 minutes, as I had known that it would. In fact this was actually one of the reasons I had decided to try mudlarking today. I wanted to remind myself to slow down, to enjoy the process of searching carefully, and not be so hung up on ‘productivity’ or ‘outcomes’ – both of which feel laughable in 2020 anyway.

So I persevered, picking my way amongst the rusty bits of metal, the crisp packets, Coke bottles, and drinking straws. Every year in England we use 4.7 billion plastic straws, 316 million plastic stirrers and 1.8 billion plastic-stemmed cotton buds. It was a flat, grey day beneath a flat, grey December sky. The water was flat and grey, barely rippling as the tide nurdled ever lower. A few off-limit jetties jutted far out into the estuary. One rumbled with a conveyor belt filling flat-bottomed barges with gravel, but all else was quiet.

For all its underwhelming winter murk, this estuary certainly has seen an astonishing history of ships, dating right back to the Romans searching for a site to establish a new settlement, Londinium. I love the romanticism of watching ships set sail, imagining all the places they might be bound for. I might have hoped for quinquiremes of Nineveh from distant Ophir, rowing home to haven in sunny Palestine, with a cargo of ivory and apes and peacocks, sandalwood, cedarwood, and sweet white wine. But I was more likely to get a dirty British coaster with a salt-caked smoke stack and a cargo of Tyne coal, road-rail, pig-lead, firewood, iron-ware, and cheap tin trays. Such musings become more accurate (if a little less flowery) with the fascinating Marine Radar app. The Maltese cargo ship Celestine slipped by, bound for Vlissingen with a cargo of cars. I hoped it would arrive before the oven-ready Brexit fiasco begins. And a Dutch Trailing Suction Hopper Dredger slurped up the estuary gloop I was searching through.

I enjoyed trying to imagine the stories behind the objects I found. An old fork, a white comb, the compulsory shopping trolley: how did these things end up in the river? A discarded condom wrapper, unopened, spoke of a disappointed date lobbing it off a bridge on the unexpected trudge through cold rain to the night bus. A golf putter, green with seaweed, had me imagining a Pitch&Putt rage, a seaside day out soured with a tantrum and the golf club arcing through the sky into the water.

What else did I find? A pair of smooth red pebbles caught my eye. A fragment of green bottle bottom –A.A & Co–, which Google reckons was made by “Alfred Alexander and his two sons, Alfred (junior) and George, who were involved in a series of English bottle factories during the last half of the 19 century and the early 20 century.” A couple of fragments of symmetrical tile. And a fragment of white porcelain decorated with blue and white lines, dots, and circles. I’m 99% certain that Christopher Columbus dined off it way back in the 12th Century, his final meal as his ship set sail from London on his way to discover the Indies…