Abstract
The film Nosferatu (1922) has graffiti created by the character of the madman Knock on the walls of his cell. This motif, which I call the 'madman's wall', has accompanied depictions of lunatics since the beginning of the eighteenth century.
This article examines the origin, transformations and functions of this motif. The popularisation of the motif originates with the longitude diagram in the last plate of A Rake's Progress (1735) by William Hogarth, which subsequently found its way into the works of Hogarth's plagiarists and influenced illustrations of asylum interiors in the first half of the nineteenth century.
The madman's wall also appears in literature, such as the popular novel The Father and Daughter (1801) by Amelia Opie, which was plagiarised and dramatised, and the legend of the poet Charles Smart, who allegedly wrote his poem on the walls of his cell. The main prerequisite for the madman's wall is the dungeon-like image of the asylum-presenting it as a prison.
It is usually the author of the graffiti who displays the signs of madness, not the wall itself. As society distanced itself from the image of the asylum as a dungeon, the madman's wall disappeared after the 1850s.
Paradoxically, many reports about the authentic wall art of asylum patients emerged in the press after the 1850s. The madman's wall in Nosferatu is the first example after an approximately seventy-year absence and could be a product of the period interest of avant-garde artists in the art of the mentally ill.