Sarah Siddons as the Tragic Muse, a 1784 painting by Joshua Reynolds, part of the Huntington Art Collections. Photo: Louis Meluso.

Sir Joshua Reynolds's portrait of the famous English tragic actress Sarah Siddons was hailed at the time of its first exhibition in 1784 as one of the greatest portraits of all time; it still ranks among the significant works of late-18th-century art. The fame and success of the picture led to the commission of a second version from the artist in 1789. The 1784 version is now in the Huntington Art Collections in San Marino, California, and the 1789 version hangs in the Dulwich Picture Gallery in London.

What can we learn from a scientific study of these paintings? Part of the work of the GCI Museum Research Laboratory involves collaborative study and technical examination of works of art with conservation and curatorial staff at the J. Paul Getty Museum. The benefits of this kind of collaboration were demonstrated recently when the two Sarah Siddons portraits underwent examination at the Getty. The impetus for studying the paintings was an upcoming Getty Museum exhibition of portraits of Siddons by leading 18th-century British painters. Scientists from the Museum Research Laboratory worked with the Paintings Conservation department of the Getty Museum and the Art Division of the Huntington to study the Reynolds paintings closely.

A comparison of the same portion of the Huntington portrait (top) and the Dulwich portrait (bottom), illustrating the varying degree of detail between the paintings. Photos: Louis Meluso.

This collaborative study—which reunited the two paintings after more than two hundred years—revealed much about the way Reynolds and his studio developed these images of the most famous actress of her day. Scientific and technical examination of the pictures was carried out by Narayan Khandekar, associate scientist at the GCI, and Mark Leonard, conservator of paintings at the Museum, working with Shelley Bennett, curator of British and European Art at the Huntington Art Collections. The team thoroughly studied the complicated array of painting materials and techniques found in the two versions of Sarah Siddons as the Tragic Muse.

Technical analyses included x radiography, x-ray fluorescence spectroscopy, polarized light microscopy of tiny cross sections from the paintings, and analysis of the binding media. For several years, the GCI has been researching the characterization of binding media in works of art, and in analyzing for binding media in the paintings, Institute associate scientist Michael Schilling employed sophisticated techniques such as pyrolysis-mass spectrometry and gas chromatography-mass spectrometry.

Analysis of the original work of 1784 reveals a complex series of changes made to the painting by Reynolds, particularly to the color of Siddons's dress, which was originally blue but ultimately changed by Reynolds to the warm yellow-brown seen today. Interestingly, in an earlier painting of famed actor David Garrick depicted with the figures of Comedy and Tragedy, Reynolds painted Tragedy in a blue dress in a pose similar to that of Siddons; this similarity suggests that the artist used the earlier painting as a model before being inspired to make these changes, which were revealed by microscopic examination of a cross section of the painting. The binding media of the two versions were shown to be very different. The Huntington version was painted in oil and oil-resin mixtures, often in many layers of paint (sometimes as many as 20). The Dulwich version used a megilp-like substance—a thick resin-oil and, in this case, wax concoction—chosen to enable the later version to imitate the thick texture of the earlier picture.

Two magnified cross sections comparing samples taken from the clouds at the base of the footstool in both paintings. The Huntington version shows layering of paint and varnish. Photo: Narayan Khandekar.

The Dulwich version, completed 5 years later, shows megilp used to simulate the bulk of paint in the earlier portrait. Photo: Narayan Khandekar.

The detailed results of this research will be presented in an essay, "A Sublime and Masterly Performance: The Making of Sir Joshua Reynolds's Sarah Siddons as the Tragic Muse," which serves as the final chapter in a forthcoming volume of essays. The publication of this volume, entitled A Passion for Performance: Sarah Siddons and Her Portraitists, coincides with the exhibition to be held at the Getty from July 27 to September 19, 1999.

The collaborative interdisciplinary efforts that formed the basis for this study have resulted in a new understanding of the diverse creative processes that produced these two famous paintings.