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In Rembrandt’s monumental Seventeenth-century masterpiece “The Evening Watch,” a troupe of Dutch civilian troopers gathers in a darkened room and prepares to march out to defend their metropolis. Rembrandt, a grasp of sunshine and shadow, strategically illuminated his topics’ expressive fingers and faces, whereas dimness hid the room’s particulars and obscured lots of the guardsmen’s our bodies.
That wasn’t all that the well-known portray was hiding, researchers lately discovered.
When conservators used X-rays to look beneath the varnish and paint of “The Evening Watch,” they found one thing sudden beneath its floor: a layer that was filled with lead.
This was the primary analysis within the portray’s 400-year historical past that mixed X-rays with spectroscopy of a paint pattern and 3D digital reconstructions, and it revealed a lead-rich layer that had by no means been seen earlier than in Rembrandt’s works, researchers reported Friday within the journal Science Advances.
Rembrandt and his artist contemporaries sometimes began a portray by first coating the canvas with a stiffening layer of glue, then including a base coat of underlying pigment, often known as a floor layer, to prime the canvas.
However there was no glue layer in “The Evening Watch.” The lead-saturated layer might have been used as an alternative as a result of it might higher defend the canvas, the examine authors recommended.
When the portray was accomplished in 1642, it was hung in Amsterdam’s Kloveniersdoelen — a musketeers’ capturing vary — on a wall going through a row of home windows, the place it might have been susceptible to break from moisture.
Rembrandt might have gotten the thought to bolster his canvas with lead from a publication in regards to the chemistry of portray, penned round that point by a doctor from Geneva named Théodore de Mayern, stated lead examine writer Fréderique Broers, a analysis scientist of microscopy on the Rijksmuseum in Amsterdam, the place “The Evening Watch” is on show.
In his writings, Mayern talked about observing a portray that had been prepped with glue, and the paint and glue layers had separated after the paintings hung for a number of years on a humid wall. In such circumstances, Mayern wrote, a canvas required a foundational layer of lead-rich oil. The researchers suspected that Rembrandt opted to work with lead “because it has extra drying properties compared to the conventional glue layer for making ready the canvas,” Broers advised CNN.
Whether or not the inspiration got here from Mayern or dialogue amongst painters, Rembrandt possible embraced the unusual approach as a promising safeguard for a portray that he knew can be displayed in a damp spot, Broers stated. The brand new findings recommend that Rembrandt was open to exploring unconventional strategies that deviated from his customary practices, to be able to execute his distinctive creative imaginative and prescient.
The researchers’ detective work was a part of a conservation and evaluation venture referred to as Operation Evening Watch, which the Rijksmuseum launched in 2019. The portray’s actual identify — “Militia Firm of District II beneath the Command of Captain Frans Banninck Cocq” — grew to become “The Evening Watch” within the 18th century, partially as a result of its heavy varnish coating and the passage of time. Because the varnish yellowed and darkened from years of grime, viewers mistakenly got here to consider that the scene passed off at evening.
Layers of varnish have been eliminated when the portray was cleaned within the Forties, lifting a lot of the darkness. However there was nonetheless a lot work to be accomplished restoring and analyzing the paintings. Operation Evening Watch is “the biggest and most wide-ranging analysis and conservation venture within the historical past of Rembrandt’s masterpiece,” with a objective of delving deeper into Rembrandt’s course of than ever earlier than and preserving the portray for a lot of a long time to return, in response to the Rijksmuseum’s website.
For the examine, the researchers mixed knowledge from large-scale scans of the portray utilizing X-ray fluorescence and powder diffraction, in addition to reflective imaging spectroscopy. These novel methods created visualizations of chemical parts and molecules, revealed their distribution, and confirmed the place crystalline constructions shaped.
A tiny paint pattern measuring simply 0.002 inches (55 micrometers) large and 0.006 (160 micrometers) lengthy was faraway from the portray, scanned after which digitally modeled in 3D — a brand new strategy that make clear how the portray was assembled, Broers stated.
“Usually you see a portray as a 2D object, however truly, it’s actually a 3D object as a result of we have now all of those paint layers,” she defined. Analysis on 3D objects requires a 3D perspective, “to actually perceive the dimensions of the particles and the way the totally different pigment particles are associated to one another.”
For many years, consultants had been mystified by the looks all through the portray of tiny “pimples” of lead crystals that rose to the floor seemingly out of nowhere. Lead is often discovered within the pigment lead white, however there was little brilliant white in “The Evening Watch.”
The tiny lead flecks have been even popping up within the darkest areas of the portray, additional compounding the enigma, Broers stated. With the identification of a lead-rich layer coating the canvas, that thriller has lastly been laid to relaxation.
“It’s a extremely large puzzle piece to know the present situation of the paint,” she stated.
One other vital discovery made throughout prior investigations was the composition of the bottom layer, which is situated above the lead one and manufactured from quartz and clay. It was the earliest proof of Rembrandt utilizing that combination, which he continued to make use of (although not solely) for the remainder of his profession.
Beforehand, Rembrandt had primed his canvasses with a double floor layer: certainly one of crimson earth after which one other of white pigment. However “The Evening Watch” was a lot bigger than any of his different works, measuring 12.5 toes (3.795 meters) excessive and 14.9 toes (4.535 meters) lengthy. A single floor layer would have been lighter, extra versatile and cheaper than his typical double layer, in response to the examine.
The successes of Operation Evening Watch come from a multi-pronged strategy to its preservation and safety, Broers added. Information from X-ray scans was evaluated alongside particulars uncovered by cleansing and conservation consultants. Curatorial interpretation offered a historic backdrop for the chemical parts uncovered within the paint and primer layers. Collectively, these numerous disciplines usher “The Evening Watch” into the trendy age for generations of art-lovers to return.
“We actually wanted the entire experience from the entire workforce of Operation Evening Watch to carry it into context,” Broers stated.
Mindy Weisberger is a science author and media producer whose work has appeared in Reside Science, Scientific American and How It Works journal.