Site Presented By
Sunday, Nov 22, 2009
Begin with the 1900 painting "Rue de Montmartre." The 19-year-old artist, fresh from Barcelona, Spain, and trying to make a living as an artist in Paris, painted the somber street scene at the urging of his dealer, Pere Mañach, who predicted such paintings would be easy to sell. A melancholy image with a muted palette, all blues and greens, it's noteworthy but not a highlight of Picasso's career.
The painting eventually fell into the hands of Harriet Levy, a San Francisco native and friend of Gertrude Stein. Her estate later donated the artwork to the San Francisco Museum of Modern Art, which still owns it today.
And that might have been the full dossier on the "Rue de Montmartre" had it not been for a conservator named Ann Hoenigswald, and a National Gallery of Art show, "Picasso: The Early Years 1892-1906," mounted by the Washington museum in the early spring of 1997.
Hoenigswald, the National Gallery's senior conservator of paintings with a specialty in the early modernist period, has worked in the museum's conservation lab since 1977. In the lab's X-ray room, Hoenigswald has installed the equipment -- X-ray machines, light boxes, infrared cameras and lead curtain -- that are common tools in her profession.
Conservators are charged with the physical care and maintenance of an artwork. "Not all museums have large conservation studios, but ones that do typically X-ray a painting before treating or repairing it or for purposes of research and analysis," says Hoenigswald. All 1,600 paintings in the National Gallery's art collection have been X-rayed, and the museum's extensive files of black-and-white X-radiograph images have been copied and loaned to galleries throughout the world.
X-ray imaging, a process invented by Wilhelm Konrad Roentgen in 1895, was used to establish provenance and uncover forgeries in modern painting as early as the 1920s. Unlike the public, which views paintings as two-dimensional images, conservators are trained to see paintings as three-dimensional objects. They seek ways to peer beneath the surface layer of varnish and paint to the under drawings, preparation layers and support structures of the canvas itself.
The X-ray process became widely popular as a research tool in 1922, when the Minneapolis Institute of Art X-rayed the interior of mummies brought back from Egypt by Howard Carter, the archaeologist who uncovered the tomb of Tutankhamen in the Valley of the Kings. Between 1926 and 1930, Alan Burroughs and Edward Forbes, both research fellows at Harvard's Fogg Art Museum, conducted "X-ray expeditions" through Europe and the United States, building a collection of X-radiographs of fine art paintings from the museums of Antwerp, Belgium; Brussels, Belgium; Florence, Italy; Rome; New York; Philadelphia; and Boston.
With great accuracy, X-rays reveal the internal structure of a painting, showing minute changes in the thickness of a layer of paint. The X-ray's fluorescence either penetrates the paint or is stopped by the atomic weight of the elements used to make the paint. Thus, lead white, lead-tin yellow, or mercury in vermilion, like human bones, all block X-rays to a different degree.
As it happens, Hoenigswald has a special interest in Picasso. In 1980, in preparation for a National Gallery exhibit, she X-rayed one of Picasso's larger paintings, "Family of Saltimbanques," and discovered three sketches underneath.
