Although Soane's trademark indirect top-lighting is much in evidence at the Soane Museum, naturally it lent itself to buildings where conventional windows were an inconvenience: a picture gallery, say, or most famously (and what was Soane's largest and most important work) the Bank of England. In such places, Soane was free to create his underworlds, shot through with shafts of light. The Dulwich Picture Gallery of 1817 - a nightmare to build and repair, making today's building failures seem tame in comparison - turned out to be one of the most influential public buildings in the world, even being restored painstakingly after a direct hit by a bomb in the Second World War. Its enfilade of galleries with lantern rooflights has been copied extensively - not least by the American architects Robert Venturi and Denise Scott Brown. They designed the interiors of the 1991 Sainsbury Wing of London's National Gallery with direct reference to Soane - though without capturing the elegance of the much smaller original building.

Dulwich gallery interior

More prosaically, the immense new Bluewater shopping centre in North Kent by another American architect, Eric Kuhne, borrows a very particular Soane motif - the "handkerchief roof" or squared-off saucer dome, which allows daylight in around the edges. There's something numbing about these scaled-up Soanian devices stretching along a huge shopping mall, but even in this relatively crude form, with none of Soane's exquisite detailing, they do the job of lighting a public space with greater subtlety than the usual sub-Crystal Palace mall roofs you get in such places.

As for the real thing, weep for the destruction of the interiors of Soane's Bank of England between 1921 and 1939 at the hands of Sir Herbert Baker, architect-in-chief to the British Empire. Baker was no mean talent, but his bombastic high-rise classicism at the Bank was not a patch on the exquisite sequence of single-storey, toplit, spaces that Soane had created from the 1790s onwards behind his windowless, intermittently decorated, perimeter wall - fortunately still to be seen. In the 1980s the Bank reconstructed a version of one of these great internal spaces, the Stock Office, as part of its museum. At the Royal Academy exhibition, however, there will rather more. The exhibition designer, architect Piers Gough, has placed a three-quarter scale painted simulacrum of the Bank's lost Colonial Office - a radically original Soane design where pillars rise into arches, thence to a dome, its top cut away in a circular skylight to reveal a crowning Ionic colonnade. Throughout the rest of the exhibition, which draws heavily on material provided by the Soane Museum, Gough has recreated the mood of Soane's architecture - though, as he remarks, such mock-ups "could never be as subtle, brilliant, and sometimes melancholic, as the master".

Gandy's vision of Soane's Bank of England as a ruin