From my desk I can see the Lakanal flats which caught fire so catastrophically on Friday. I've looked at the modernist slab block, end-on, almost every working day for the last three years. OnFriday afternoon there was thin grey smoke coming from one window. As I went out into the street a woman from across the road told me that she'd just called the fire brigade. While we watched thesmoke turned black and then with a muffled sound, somewhere between a thud and a roar, flames burst out of the front. Glass and burning debris started to shower down. After twenty minutes or so Ileft. I wasn't doing any good. People were running towards the estate but by this time the police had tape up and were holding them back.

Lakanal, named after Joseph Lakanal (1762-1845), the French revolutionary educationalist, is part of the Sceaux Gardens estate. It was built in 1955-59 in a haze of post-war Corbusian enthusiasmfor all things French. The other blocks, mostly lower rise, include Voltaire, Fontanelle and Racine. Lakanal's twin high-rise is Marie Curie. In summer, with the trees in leaf shadowing itspale-green panelled balconies, Lakanal could pass for not too poor a relation of the Unité d'Habitation. Designed, nominally, by the Southwark borough architect F.O. Hayes, it was probably the workof an Austrian in his office, Felix Trenton.

Sceaux Gardens was only one of the later experiments in social housing in an area dense with them for over a century. I work in the earliest, Pilgrims' Cloisters, built by William Peacock in 1837on the model of an Oxford college, and intended as a rest home for aged pilgrims. The Pilgrims' Way passes nearby and there was little else here then. Across the road in Havil Street is the circular Victorian workhouse hospital. The art nouveau South London Gallery is on the main road and the Arts and Crafts grammar school on Wilson Road.They mark, like tree rings, succeeding fashions in architecture and philanthropy. The terrible end of the Sceaux Gardens experiment – and it surely will be the end, they will have to take the blockdown – should not be blamed too hastily on anyone, even its architect. The fire seemed to travel in a zig zag up and down the building. It will take time to understand what happened. Today theestate is full of subdued activity: firemen and police and residents waiting for answers.