Its structure resembles that of a Chinese lantern rather than a miniature paper theatre. It is made of circular-shaped bellows attached to a top panel with viewing lens and a bottom panel into which prints can be inserted. These prints seem to come from different series, as in addition to views of Paris. The prints, when viewed outside the device in reflected light, show views by daylight of various popular destinations such as the ‘Rue de Rivoli’ or ‘Jardin des Tuileries’. When viewed through the peephole, against a strong source of light, the transmitted light changes them to night scenes in which small holes pierced in the prints become the stars, the moon, or lit windows and street lamps.

In two instances however, the scene is dramatically changed: the tranquil ‘Bains de Dieppe’ with couples leisurely walking along the beach is transformed into a frightening shipwreck scene and in ‘Le tunnel de Rolleboise’ a train bursts into view where before there was only an empty tunnel with some men at work.

The ‘day’ picture is printed on the recto (front), while the ‘night’ picture is obtained by painting the verso (back) side in black and other dark colours. The contours of the train and the lighter areas were then drawn and defined using a kind of sgraffito technique. The dark paint was thus scratched away in places where the light was meant to shine through.

The image of ‘Les bains de Dieppe’ is a little more complex. The hidden picture is painted with dark and light colours on the back of the print and completed by drawing the waves and creating light by thinning the paper in certain areas to enhance the transmitted light. The illusion is reinforced using a painted paper lined to the back of the panel which creates the coloured background.