Delphine Syvilay

Now an associate professor at Sorbonne University Abu Dhabi, Delphine Syvilay experienced the Notre-Dame de Paris restoration project firsthand. Balancing medieval relics and cutting-edge technology, she unveils the behind-the-scenes of an extraordinary endeavor where heritage urgency meets personal adventure. Here’s the portrait of a passionate scientist who brings stones and metals to life.

From Art History to Lasers: Delphine Syvilay's Unique Journey

As a teenager, Delphine Syvilay dreamed of exploring museum halls and decoding the mysteries of history. Her passion for art history and archaeology fueled her travels, fostering a unique bond with monuments. “I hoped one day to create a special connection with a monument,” she recalls. This intuition would later prove prophetic.

While pursuing her physics degree at Pierre and Marie Curie University, she discovered an interdisciplinary course on heritage materials that bridged the gap between humanities and hard sciences. “It was a revelation,” she says. Her path then led to a master’s degree in heritage materials at Paris 7 University, an introduction to conservation sciences, and an internship at the Historical Monuments Research Laboratory (LRMH), where she specialized in archaeometry. “Archaeometry uses sciences like physics, chemistry, and geology to analyze and study heritage materials,” she explains.

Freshly graduated, Delphine joined LRMH as an engineer tasked with examining the lead-covered roof of Beauvais Cathedral, a gem of Gothic architecture. This experience paved the way for her doctoral research in partnership with the University of Cergy-Pontoise. “I worked on developing laser-based spectroscopic tools to analyze heritage materials,” she says. From metals to mural paintings, she explored the light that reveals the invisible.

After earning her doctorate, she pursued postdoctoral research in Bordeaux. Two years later, she returned to LRMH for a three-month contract. Then the unthinkable happened: Notre-Dame de Paris went up in flames, threatening centuries of history. Her expertise in lead restoration proved invaluable, transforming her short-term contract into three years immersed in one of the century’s most significant heritage restoration projects.

Notre-Dame: A Race Against Time

Delphine vividly remembers the evening of April 15, 2019. “I was about to leave the laboratory when the news of the fire broke,” she recalls. A week later, she stepped into the ravaged cathedral. “We were among the first to access the site,” she says. Despite the destruction, she was struck by the cathedral's beauty. “I’d never seen Notre-Dame so stunning. The gaping hole at the crossing let in light that grew stronger as the stained-glass windows were removed,” she remembers emotionally.

Inside the silent, massive structure, teams of archaeologists, architects, researchers, and climbers worked tirelessly. Delphine donned a ventilated mask to protect herself from lead while sorting debris collected by robots in unsafe areas. “It was physically demanding,” she admits. “Looking back, if we had known the magnitude of the task, we might not have dared to take it on.”

Alongside colleagues from the National Institute for Preventive Archaeological Research, the Regional Archaeology Service, the Research and Restoration Center for Museums of France, and the CNRS, she spent over two years meticulously cataloging fragments of the roof, spire decorations, iron frameworks, nails, and clamps. “It was like reconstructing an enormous puzzle,” she says.

Innovative Solutions for Restoration

The Notre-Dame fire posed new challenges for researchers and restoration teams. “How do we choose the best lead alloy for the new roof? How do we avoid the darkening observed on other cathedrals?” Delphine explains. Experimental setups were created to study the roof’s angle and lead laminating techniques. “It was essential to restore the cathedral using original methods while ensuring environmental safety,” she emphasizes. Her team also provided critical data to help estimate the amount of lead released by the cathedral and propose technical solutions to mitigate environmental impacts.

Collaboration with other specialists was vital on this extraordinary project. “We were all fascinated by each other's work, and the mutual support among professionals was remarkable,” Delphine says. One climber drew her attention to inscriptions on the cathedral's stones. What began as a curiosity evolved into a full-fledged scientific project. To document the markings, Delphine even trained as a climber to access the cathedral’s 70-meter-high exterior walls and towers. “I wanted to conduct the surveys myself,” she explains.

The findings were extraordinary: over 1,300 stone markings and 200 graffiti, ranging from 1612 to the day of the fire, were documented. “The oldest graffiti we found dates to 1612, and the most recent is from the day of the fire,” she says. With the restoration and natural erosion, some of these inscriptions will vanish. “Documenting them was crucial to preserving their history,” she adds.

Delphine Syvilay’s journey showcases the power of interdisciplinary science in heritage conservation. Her work at Notre-Dame de Paris stands as a testament to the human dedication required to preserve history, turning challenges into discoveries that illuminate both the past and our collective identity.