Invisible Characteristics of Paintings Revealed by Fogg Museum Workers

Proof that Veronese intended to paint Venus as a half naked lady rather than as a nude Renaissance goddess has been, supplied by workers at the Fogg Art Museum who have been using the X-ray to test the authenticity of masterpieces. The rays have uncovered the first version of the Italian artist's "Mars and Venus" where the figure of Venus was half draped.

Examinations like this one under the direction of Alan Burroughs, research worker, are given masterpieces before they are placed on exhibit. Put under the X-ray, brush strokes stand out clearly revealing the characteristics of the painter. For instance, the brush strokes on "St. Luke and the Virgin" have led Mr. Burroughs to believe that Dirk Bouts, and not Roger van der Weyden, was its painter.

Copies are easily discernible since the work is thin, hard, and precise in contrast to the luxuriance of the original. If the picture is damaged in any way, these faults will be revealed by the shadowgraph. Another process, that of ultra-violet light, makes the pigments of different ages fluoresce differently and thus the age of the work and retouching can be detected.

Museum officials have also been cleaning some Chinese wall paintings, almost a thousand years old, which have been taken in pieces from the walls of caves. First the ancient pigment film is given a thorough cleansing and several layers of Japanese tissue and muslin are glued to the clean surface.

The clay on which the picture was originally painted is then scraped from the back side and the inner surface of the paint is cleansed. A new base of clay on presswood is affixed and the muslin-tissue support is dissolved from the face. Thus only the pigment, about a sixteenth of an inch thick, is kept intact during the process of restoration.