Observations: From the side streets and the alleys: London rediscovered

Old photographs – their particular grain, their uncanny illumination of both a living moment and the death of time – can possess extraordinary traction. I'm studying a photograph in a new book, Lost London, by Philip Davies, and it's hard to look away.

The width of the alley in the picture is no more than seven or eight feet. Chalked onto the flaking wall where Moss's Alley joined Ladd's Court near Bankside, London, on 16 May 1912, are the words: "Chocolate Club Held Here". Up the cut, by their grimy doorsteps, impoverished mothers and cloth-capped men gaze patiently at the camera recording an existence being gazed at with equal patience by yet another stranger on a November day in 2009.

This was a part of the city that Dickens had described 75 years earlier in The Pickwick Papers as "mean and close; poverty and debauchery lie festering in the crowded alleys." But the words trigger a sentimental literary reaction that simplifies the meaning of photographs like this.

Lost London is a compendium of images taken between the 1870s and 1945, whose power lies in their teeming plurality of details, half-tones, and layers of suggested human narrative. One can't look at the dozens of crude iron bridges joining two lines of warehouses at Shad Thames in 1910 and not get a flash of Fritz Lang's film, Metropolis, made 17 years later; or wonder which of the three nursery maids in the down-at-heel room in Deptford was about to pick the copy of Goosey Goosey Gander from the mantelpiece and read it to the 20 toddlers packed in around them; or imagine what grim thing might just have taken place behind the abandoned, ashen facade next to John Warner Ltd, Iron Founders, in Stepney Causeway on 10 February 1943.

Lost London by Philip Davies is published by English Heritage; Lost London exhibition is at Kenwood House, London NW3, from 23 January to 5 April