Mike Pitts has an interesting feature on his blog regarding the Soane Model of Stonehenge which is on show at the exhibition -

“Chris Evans has written about the context of Soane’s archaeological models in two similar papers, “Megalithic follies: Soane’s ‘Druidic Remains’ & the display of monuments” (Journal of Material Culture, Nov 2000, 347–66) and “Modelling monuments & excavations” (in eds S de Chadarevian & N Hopwood, 2004, Models: The Third Dimension of Science, 109–37). He tells us that Soane probably bought his Stonehenge model in 1832 from another collection in London. But no one, as far as I am aware, has examined the model for what it may tell us about Stonehenge."