This book concerns a dark convex mirror that was well-known to artists and natural philosophers in the eighteenth and nineteenth centuries. It was usually small enough to be held in one hand, and usually protected in a case of the sort that would later be used for daguerreotypes. It was thought to [End Page 865] make a scene appear more pleasing than it would be to unaided eyes. Indeed, it was often known as a Claude mirror, or a Claude Lorrain mirror, as it showed the world as depicted by the French landscape painter who established perspective not by compositional lines, but by gradations of tone that were themselves governed by light.
Arnaud Maillet, who was trained as an art historian, is able to explain the ways in which a Claude mirror creates images that conform with once-popular theories of how an artist should use color tones and values to produce a beautiful painting. He also provides numerous examples of these items appearing in pictures and of them being discussed by artists and travelers. But he goes further, much further. After failing to find any Claude mirrors in any of the large institutional museums in France, Denmark, Austria, or Germany—or at least any examples that these museums would acknowledge—Maillet set out to explore ideas about the dark side of mirrors, especially those that were dark or curved or both, and found that, since antiquity, objects of this sort have often been associated with demonical or other perverse activities.
A woodcut attributed to Albrecht Dürer illustrated the adage that the convex mirror is the devil's ass. John Dee in Elizabethan England had several black mirrors that he used for divination. The curved black mirror in the Musée National des Arts et Traditions Populaires has not been given an inventory number—thus it doesn't officially exist—and is never put on exhibition because "someone who knows how to cast spells would be able to use it even through a glass case" (p. 31). Going further still, Maillet addresses such notions as whether a blind person can see the future, whether a mirror might show death, and what it means to see in a mirror darkly.
Maillet received his doctorate at the University of Paris, and acknowledges the influence of Jean Baudrillard, Michel Foucault, and Jacques Derrida. He works impressionistically, skipping from one culture to another and crossing vast expanses of space and time within a single paragraph. This style might appear challenging to those who prefer a more linear approach, but the results are well worth the effort. Indeed, I found this book to be the most fascinating and sophisticated account of an optical instrument I have ever seen.
Deborah Warner is a curator of physical sciences at the National Museum of American History, and does not recall having had any untoward experiences with the Claude Lorrain mirrors in the museum’s collection.