They say that history is written by the victors. In Antoine Lavoisier’s case, he was not one of them. It’s a well-known fact that he was denounced and guillotined in 1794 for being a wealthy tax collector, during the French Revolution. He was, of course, also a famous and brilliant chemist, whose influence in the field cannot be understated (earning him the moniker ‘the father of modern chemistry”). Recent analysis of a famous 1788 painting of him and his wife, Marie-Anne, shows that the painting was modified to show less of his wealth and more of his science.
Dorothy Mahon, a conservator at The Metropolitan Museum of Art, noticed some oddities in the painting while carefully removing a degraded layer of varnish. Cracks in the paint seemed to show other colors beneath, and tiny cracks on the tablecloth seemed to reveal that the final layer of paint was a later addition. This prompted further analysis.
Fig. 1: Signs of the original painting showing through the top coating
Firstly, infrared ray reflectography was utilized to reveal what lay beneath the painting’s surface. IRR is a technique where infrared light is cast on the painting, which can pass through the surface layer. By measuring the infrared light that’s reflected by different areas of the painting, things underneath the surface can be seen. The IRR applied to this painting showed several things -- the initial sketch that was painted over being modified several times, changes in facial expressions, a wastepaper basket that was removed from the final product. Most interestingly, it revealed several discontinuities that weren’t as easily explained by the painting process -- an elaborate table under the tablecloth, a blurry object on the table, a strange smudge on Marie-Anne’s head.
This prompted further analysis. For a more accurate view of what lay beneath, macro X-ray fluorescence mapping was utilized. This technique uses X-rays to detect the elements in a sample. The X-rays bombard the sample, and the emitted energy is measured. These emissions are cross-referenced with atomic spectral lines to determine the composition. Once the elements in a sample are known, it can be inferred what pigments were used to color the painting, and it can thus be determined what the painting looks like under the surface. To help with determining which pigments were used, seven small paint samples were taken from the painting and analyzed.
The macro X-ray fluorescence elucidated the changes to the painting. Most prominently, Marie-Anne originally had a large flamboyant hat, with ribbons and feathers. The table was originally a lavishly gilded wood, before it was covered in the red tablecloth seen today. Some of the scientific instruments in the painting were added later, and Lavoisier was originally wearing a red mantle that was removed. All in all, the painting was modified to show much less wealth, and instead focus on Lavoisier’s scientific pursuits.
Fig 2: The image as it is seen now, under IRR imaging, and reconstructed after MA-XRF analysis
The painting has since been revarnished and sits at The Met, the same as it always has. It looks the same as it did before, of course, showing Lavoisier and his wife as the great scientific couple they always were. But it’s worth thinking about, now, how carefully that image was chosen to depict them as it does.
References:
Blakemore, Erin. "Tech Uncovers Changes to Portrait of a Chemist-Couple, Victims of Reign of
Terror." The Washington Post, 11 Sept. 2021, www.washingtonpost.com/science/
art-restoration-science-met-lavoisier/2021/09/10/f2100e0a-10dc-11ec-9cb6-bf9351a25799_story.html.
Accessed 26 Oct. 2021.
Centeno, Silvia A., et al. “Discovering the Evolution of Jacques-Louis David’s Portrait of Antoine-Laurent and Marie-Anne Pierrette Paulze Lavoisier.” Heritage Science, vol. 9, no. 1, Springer Science and Business Media LLC, 30 Aug. 2021. Crossref, doi:10.1186/s40494-021-00551-y.
Centeno, Sylvia A., et al. "Refashioning the Lavoisiers." The Metropolitan Museum of Art, 1 Sept.
2021, www.metmuseum.org/perspectives/articles/2021/9/david-lavoisier-conservation. Accessed 26
Oct. 2021.
Your title is descriptive and ok. The graphics are well-chosen and very effective getting at the both the science and the art. Your explanations of the scientific methods are pretty good. Concise and helpful. The Washington Post is a good general interest source indicating a topic ok of wide general interest. And, of course, Lavoisier's famous fate in the revolution is of great general interest. The implied political significance of the changes revealed by scientific examination of the painting is tantalizing. Overall a particularly effective post.
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