The long overlooked staircase by Hogarth at St Bartholomew’s Hospital has been cleaned and restored in a £9.5 million scheme. Murals are of course the original site-specific artworks, and you have to enter a working hospital to see this one. Literally: turn right for the clap clinic, turn left for the Hogarth mural. Metres from them, you push open a heavy wooden door, and there, in what used to be sepulchral gloom, were Hogarth’s largest paintings. But Hogarth preferred his paintings crisply detailed, and he authorised the mural to be cleaned just a decade after its completion.