There is a series of shots, close to the beginning of the film, of the stage rigging, with those beautifully coiled ropes -- Homans compares them to a sailing ship, but I think your machine image is even closer. In the Margot Fonteyn-narrated series, The Magic of Dance, there's a backstage sequence filmed in Copenhagen at the Royal Theater, demonstrating 19th century 'special effects' -- this feels very similar.