The Conveyor

Designed by Marc Isambard Brunel and completed in 1843, the tunnel under the Thames between Rotherhithe and Wapping was constructed using Brunel’s invention, the cast-iron “Tunnel Shield”, enabling thirty-six workmen to excavate in separate cells, the whole device being slowly moved forward as the tunnel grew.

Originally a foot tunnel, it was converted to railway use in 1869, and eventually became part of the London Underground.

This folding paper peep show enables the viewer to see foot passengers promenading in the tunnel. The arches help to indicate perspective. It was probably sold as a souvenir. Even before completion of the tunnel, the canny businessman Brunel allowed visitors to tour the works, at the cost of one shilling.
Wikipedia : Thames Tunnel