London School of Economics, Sardinia Street WC2

I must admit I was a bit taken aback by this when I first saw it. The corner of the old Public Trustee Office, built by the Office of Works in 1912 ("Soothingly restrained" - Pevsner) seems to have been punched in by a roadside bomb, crushing bits of architecture up into a jumble held by some sort of glue over the heads of oblivious pedestrians hurrying to catch a bus in Kingsway.
Looking up, the corner gets even odder. The blank windows line up with the windows of the original facade but otherwise make no sense at all, being assembled from bits of carvings just as randomly as the wreckage below.
It is, of course, art. The original angled corner has been covered by a fibreglass screen by twice-Turner-prize-nominated Richard Wilson. Called Square the Block, it is moulded from stuff called jesmonite, a lightweight acrylic fibreglass, to match the colour and texture of the original so well I was convinced it was stone.
The work was commissioned as part of a complete rebuilding of the former offices as the London School of Economics' New Academic Building, full of lecture halls and 'social interactive spaces', whatever they are. The architect, Nick Grimshaw, provided Wilson with drawings of the old facade to work from. It was unveiled a couple of months ago.
I'm not sure. While I'm a big fan of modern sculpture, this one undermines the original classical composition in quite a rude way although the LSE inevitably says it 'both mimics and subtly subverts the existing façade', as prime a slice of contemporary artbollocks as I have seen in a long time.
It would have been perfectly acceptable, interesting, and a great experience as a temporary thing, like the fourth plinth in Trafalgar Square, but Square the Block is up there for good. Soon, the joke will look very jaded.
More in an LSE press release here.