How a 19th-century estate agent offered 3D property ‘walkthroughs’ before the dawn of the photography age

The Cosmoramic Room in P.T. Barnum’s American Museum, New York. Illustration from the museum’s official guidebook.

If you’re thinking about moving house or just feeling nosy about your neighbours, your first port of call may be an online property marketing site: Rightmove and Zoopla in the UK, Zillow in the US or Magic Bricks in India.

They offer 3D plans of their properties and a video walkthrough, sometimes with added interactive tools. It all seems very modern – yet it turns out, at least one pioneering London estate agent was offering its clients 3D visual walkthroughs long before the advent of commercial photography.