The Metropolitan Museum of Art. Art and Autoradiography: Insight into the Genesis of Paintings by Rembrandt, Van Dyck and Vermeer. New York, 1982
NEUTRON AUTORADIOGRAPHY has been used in the investigation of art objects for nearly 20 years. This analytical method has been applied to paintings, drawings, photographs and manuscripts. It is especially useful in painting studies in that if often allows one to observe with high resolution the complex overlapping structures of multiple pigment layers applied beneath the surface.
The book Art and Autoradiography: Insights into the Genesis of Paintings of Rembrandt, Van Dyck and Vermeer should be viewed as an example of the technique applied to well known paintings, with the art historian, conservator, and museum scientist working together. The book represents a direct approach, integrating several scientific methods and scholarly disciplines to best answer questions about these works. Although scientific details are presented, the main emphasis is on the interpretation of results, not on how the results were obtained. The text is easily understood and appreciated without a background in physics, chemistry, art history or conservation.
It is refreshing that the authors openly describe the limitations of this method (for example, some important pigments simply cannot be detected and studied) and do not attempt to give the impression that neutron autoradiography is a panacea. They clearly indicate that “autoradiography by itself cannot be touted as the final word” and describe its use with other complementary methods such as x-ray radiography and analysis of pigment sample cross sections. X-ray radiographs show some details lost to autoradiography and the reverse is also true; the authors clearly illustrate that they should be used together whenever possble.
Note that, for several reasons, neturon autoradiography cannot be done everywhere or on all material. First and foremost, one must have a nuclear reactor with an unusually large area neutron beam which has specific flux characteristics. Very few facilities now exist. Secondly, the painting will be continuously analyzed for two months or longer, requiring skilled personnel to handle the painting, the photographic films and necessary security restrictions. In addition, the painting should be on a canvas support as most specialists feel that panels are fragile and too easily damaged.
A partial outline of the results may illustrate how neutron autoradiography can help interpret the works of an artist. The discussion of Van Dyck's Saint Rosalie Interceding for the Plague-stricken of Palermo offers the widest variety of applications to a single painting. The autoradiographs clearly indicate the use of underpainted sketching; no other oil sketches of Van Dyck for this period have survived. Also shown, through changes in composition, is the evolution of design. Most intriguing perhaps, is the appearance of a portrait in the autoradiographs (hints are seen in the x-ray radiograph) that develops so distinctly that identification can be made by comparison with a self-portrait of Van Dyck. The image in a good neutron radiograph is exceptionally sharp and the reproductions found in this book are very good. In addition to the art historical results, a great deal of information is provided for the conservator relating to tears, losses, repairs, and restoration in this painting. In the study of Rembrandt's works, the major portion in this book, further examples of the types of information mentioned above are illustrated. In addition, more subtle effects revealed in the autoradiographs, such as canvas weave and the methods of ground application, are discussed. Results also show that brush strokes, obscured by darkening of pigments, are clearly resolved in the autoradiographs, helping support theories of how Rembrandt worked.
As previously mentioned, the plates are clear and sharp and the quality of production is high. The text is generally clearly written with some slight lapses in style. For example, in section 3, the authors state that “a quantitative estimate can be made of relative abundances” of elements in the painting. Shortly thereafter they concede “these data cannot be considered as precisely accurate”. Are they suggesting they are making educated guesses? There is at least one typographical error, i.e.,Table 1 should list the radioactive isotope Mn-56 not Mn-54. These slight distractions certainly do not detract from the overall quality of this publication.
It is easy to recommend this book to anyone having an interest in the analysis of the inner structure of paintings and in how this information may be used in the study of some specific Dutch and Flemish works or to those wishing to learn how these methods work and are used in general. It will be a welcome and important addition in the library of conservator, scientist or historian.
As a footnote, it should be mentioned that, although the future of the Brookhaven Medical Research Reactor (where the work reported in this book was performed) is cloudy, efforts by the Smithsonian Institution and the National Bureau of Standards will ensure that a facility will be available for the continuation of development and application of this important research.