The Victorian City: Everyday Life in Dickens's London, By Judith Flanders

Charles Dickens was a walkoholic. Physically restless and rarely able to sleep, he would cover five to 30 miles a day in and around London, sometimes walking all night, and keeping up (he reckoned) a steady fast pace of four-and-a-half miles an hour. His speed didn't stop him observing things: he compared his mind to a photographic plate. Give Dickens the name of almost any London street, wrote a contemporary, and he would be able to tell you "all that is in it, what each shop was, what the grocer's name was, [and] how many scraps of orange-peel there were on the pavement".

His constant watching and eavesdropping fed his novels, and he paced out a London which eventually took on his name – although, as Judith Flanders points out, in his own time "the way that people lived was not Dickensian, merely life." The Victorian City investigates that life in every particularity. It complements the author's The Victorian House, which dealt with the domestic realm. Now Flanders takes us into the streets, and walks us through them from dawn to night pointing out people and objects of interest. You get the feeling that she, too, would miss no scrap of orange peel, but she would also tell you why that piece of peel was there and what it reveals about attitudes to fruit or litter. The effect is at once meticulous and gripping. Early on, she directs our attention to the composition of the streets. I'd vaguely thought they were cobbled, but some were made of asphalt, cast iron or even wood, which was quiet under the horses' hooves, reducing the omnipresent racket – but the wood rotted and the experiment failed. Others were of tar macadam, rolled out with heavy cylinders; this made it convenient to move road gutters to the edges rather than having them in the middle, and so helped to create the pedestrian pavement.

Londoners walked a lot; Dickens was not alone. If you worked a 12-hour day, you might also walk for an hour or more to get to work. On the way, you could grab a coffee and a bun from street stalls. Food was on sale everywhere: you could buy whelks, periwinkles, crab-claws, sheeps' trotters, or cooked potatoes from heavy, steamy vats. Other vendors sold tea-leaves for cleaning carpets, or novelty toys.

Offices could be as nasty as the blacking factory where Dickens worked as a boy, filled with mould and rats, and the worst houses could be as terrifying as the shanties dangling over the river on Jacob's Island, where Bill Sikes meets his end in Oliver Twist. Others were more elegant, and there was a thriving nightlife with singalong inns and theatres, where you could pick up popular catch-phrases like "How are you off for soap?" or "What a shocking bad hat!" Speaking of hats, almost everyone had one, including children. They indicated your status; only the most desperate would find themselves without.

As darkness fell, the lamplighter passed, carrying an oil barrel and balancing the lamp covers on his head. Then came the prostitutes, who might cross the bridges to the West End while the watercress-sellers walked the other way to get home. These ubiquitous greenery vendors worked the longest days of all, collecting produce at 4am and rarely finishing before ten. They exemplify the sheer strangeness of the past – its unassimilability. Few of us even eat the stuff any more, let alone buy it on the street in late evening. Perhaps to understand the popularity of watercress sellers would be to understand a whole world.

Flanders says that Dickens appealed to contemporaries because he gave them a voyage into the unknown: into parts of London they did not know and where they would not venture. She does something similar for us. The strangeness remains, but the voyage is unforgettable.

Sarah Bakewell's life of Montaigne, 'How to Live', is published by Vintage

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