Although it has generally been assumed that Nicolas de Pigage wrote the Düsseldorf catalogue because he signed the introduction, current research identifies Jean-Charles Laveaux, a young linguist from France, as the main author. Laveaux's familiarity with the Düsseldorf paintings and their display is corroborated by his detailed references to color and understanding of Krahe's display principles.
One of the writer's central aims was to interpret the intricate etchings for the reader. In the reproductions, most of which are only thumbnail-size, the subjects are not always easily recognizable. Laveaux's commentary provides detailed descriptions. He first discusses each painting's composition and style and then concludes with its unique qualities. This structure can be seen in the description of Carlo Cignani's Assumption of the Virgin (see central image, below). Fundamentally complementing each other, the etchings and text make clear that Pigage, Mechel, and Laveaux sought to make the art accessible to an educated public.
Catalogue Text for Carlo Cignani's Assumption of the Virgin (translated from French)
Her head elevated and her arms open toward heaven, the Virgin is elevated amidst glory and a choir of angels and cherubs, with an expression of liveliness and pure happiness. She is seated on the clouds, which are supported by angels, while others scatter flowers all around. She is dressed in a red robe with ample blue drapery over it, passing from the back to the front of the body and partially around her right arm...
This painting is one of the largest and most beautiful by Cignani. It has all the qualities that distinguish this master's good works: fertility of genius, skillful composition, accuracy of drawing, artful drapery, freshness of color, and, above all, noble expression. The figure of the Virgin has a sublime character.