Vüe d'Optique Representant Le Profil du Palais de Petersbourg.

Vüe d'Optique Representant Le Profil du Palais de Petersbourg. Translation: Exterior facies Palacii Petropolitani 15th optical view representing the profile of the Petersburg Palace. Hand colored engraving, (16 x 11 inches) Artist unknown
"So-called optical print illustrating a perspective view of the portico of a Palace in Saint Petersburg. Published by Daumont, a well-known publisher of optical prints, established in Paris, at rue St.Martin. Engraved by Loyer.
In the eighteenth and nineteenth centuries, there were many popular specialty establishments in Paris, Augsburg and London which produced optical viewing devices and special engravings to be viewed through them. In the 18th century, the optical print or vue optique came into existence, whose exaggerated converging lines were intended to produce the optical illusion of deep recession.
The viewing devices for which these perspective prints were produced consisted of a lens and a mirror, requiring the use of reversed or mirror-image pictures." Pulas Swaen