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Colors of a 17th-century Swedish battleship The Vasa lay underwater for 333 years before being salvaged. Could investigators work out how it had been originally painted? ustavus Adolphus, the Swedish king, was reportedly furious. It was 1628, and the king was leading Sweden in a war against Poland. He had ordered new battleships to be built, with the Vasa as the pièce de résistance of the fleet. The Vasa was equipped with 64 guns on 2 gundecks, a novelty at the time, and sported an ornate facade at the back, sculpted with Greek gods, ancient Roman motifs, and the Vasa family’s insignia. But, while the king was in Poland, he received news that the battleship had sunk. On Sunday, August 10, 1628, the Vasa embarked from Stockholm harbor on its maiden voyage. Crowds of spectators jammed the piers to watch the momentous occasion. The Vasa set sail, opened the gun ports, and fired a salute. But within a few minutes, the battleship began to keel over. It almost righted itself but keeled over again. Water started to pour in through the open gun ports, and, in front of the horrified crowds, the Vasa sank. Of the 150 people estimated to be on board, 30–50 men, women, and children drowned. An investigation determined that no single party was to blame and concluded that the ship was well built but not correctly proportioned. The Vasa was left on the bed of the Baltic Sea, just off the coast of Stockholm and, over time, forgotten. It wasn’t until 1956 that Anders Franzén, a shipwreck specialist, found the 17th-century battleship and garnered support to salvage it. The operation got under way on April 24, 1961, and Sweden came to a standstill to follow the events on TV, by radio, or at Stockholm harbor. Whether the battleship would survive its rescue was uncertain. But after 333 years on the Baltic seabed, the Vasa finally rose out of the water. “I was 19 years old at that time,” remembers Peter Tångeberg, an art historian and restorer. “I went to 6690
Stockholm to look at the ship. It was very exciting.” Preservation of the Vasa had to begin immediately. The Vasa, which measures 69 m in length, 11.7 m in width, and 52.5 m from the keel to the top of the
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The back of the Vasa carried sculptures to symbolize the might and glory that the ambitious Gustavus Adolphus envisioned for his kingdom.
main mast, is the single largest wooden object that has ever been preserved. The battleship was sprayed extensively with polyethylene glycol to replace the water in the wood to prevent it from shrinking and breaking as it dried.
Was analysis possible? In 1987, the construction of the Vasa Museum in Stockholm was under way. People involved in the Vasa preservation had made a replica of the Vasa family’s coat of arms from the facade at the back of the battleship, painted it blue, and gilded it. They wanted to hang it on a wall in the exhibition hall, but the architect of the hall balked. “She found it
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ugly,” says Tångeberg. To settle the disagreement, she called Tångeberg—she knew of him through a mutual friend— and asked him to give his opinion on how the coat of arms must have been originally painted. “So I went there and I said, ‘Ah, I don’t think it could have looked like that, but you must have done some chemical analyses of paint samples,’” recounts Tångeberg. “They said, ‘No, we have not.’ Then they asked, ‘Do you think it is possible to find colors now, after conservation?’ I said, ‘We don’t know, but we can try.’” Tångeberg specialized in medieval church sculptures and altarpieces. Figuring out whether or not there was paint on the Vasa sculptures presented a challenge. “I hadn’t worked with waterlogged wood. I hadn’t worked with ships. I didn’t do much with sculptures from the Renaissance and Baroque times. There wasn’t any literature you could go to. Everything was new,” says Tångeberg. He first tackled the thousands of large color photographs that were taken of the Vasa sculptures as they were rescued from the water. Tångeberg studied the photographs and noted that there were visible differences on the sculpture surfaces. “Some surfaces were smooth; some were not. Some were gray; others were black and brown,” he says. Tångeberg deduced that the differences must have been due to paints. He also studied 17th-century church sculptures and 17th-century Dutch maritime paintings (the chief shipbuilder of the Vasa was Dutch). From his analyses, Tångeberg began to form the hypothesis that the sculptures on the Vasa must have been painted in a variety of colors. To see whether the chemical compositions of paint residues on the sculptures could be deciphered, Tångeberg turned to Unn Plahter at the University of Oslo. Plahter is a chemist who spe© 2006 AMERICAN CHEMICAL SOCIETY
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Was it really paint? More than 1000 samples had to be analyzed, and each one required meticulous work. The investigators broke the project into steps. First, Tångeberg recorded whether a sample came from a human figure, leaves, fruits, or any other object. He made cross sections of the sample and took color images of all of them. The cross sections were next sent to Plahter, who analyzed each one by SEM, recorded the elements that were found, and noted whether they were the major or minor elemental components. The analysis was especially difficult because the samples were discolored into blacks, browns, beiges, or grays. “If you have a painting or polychromatic sculpture, you can see the colors,” says Tångeberg. It’s obvious what’s painted in red, blue, or yellow. But with the Vasa samples, Tångeberg says, “We didn’t even know if we had found color. There were secondary sediments because the sculptures had been in water for so long. These sediments had almost the same elements as some of the colors.” Tångeberg and Plahter spent a considerable amount of time working out whether elements they found belonged to paint or to sediments such as rust that came from modern-day ships sailing through Stockholm harbor. But because they analyzed a large number of samples, the investigators started to notice the recurrence of some elements. “Elements such as copper, arsenic, cobalt, and lead often were indicative of original paint,” says Plahter.
HANS HAMMARSKIÖLD FOR THE VASA MUSEUM
cializes in medieval paint analysis and had experience in studying elemental compositions of paint by scanning electron microscopy (SEM). When Tångeberg first approached her with the Vasa samples, Plahter took them as a project to do in evenings and on weekends. “I didn’t know there would be so many samples!” she laughs. When Plahter determined that SEM would work on the samples, Tångeberg drew up a research proposal and submitted it to the museum in 1990. “I said [to them], ‘I need 10 years and 2 million kronor. I will find out something,’” he says. A color reproduction of what the Vasa family’s coat of arms must have originally looked like on the battleship.
The paints hadn’t remained static, though, and often reacted in the Baltic waters to form other compounds. “There are lots of sulfides in those waters, so [for instance] red lead would go to lead sulfide,” explains Plahter. It became obvious that coarse-grained pigment particles were more resistant to chemical reactions than fine-grained particles. Coarse-grained red lead frequently kept its color, but fine-grained red lead turned into a black sulfide. But one yellow pigment remained stable. “Orpiment is an arsenic sulfide and, as a sulfide, it liked the environment of sulfides,” says Plahter. Gold foil, which was used for gilding, also survived reasonably well in the Baltic waters. As Plahter found the elements, they repeatedly went back to Tångeberg’s initial records to confirm whether the elements really indicated paints. For example, copper was the main element in green paint. Plahter would check with Tångeberg to see where a sample with copper came from; if it had come from a leaf or a grape, they could reasonably conclude that they had found the residue of a green paint. Although cobalt wasn’t always detected, fragments from certain areas of sculptures containing potassium and silicate were thought to be smalt, a blue pigment. The investigators went on to discover four different blue paints, one of which, indigo, was
one of two organic pigments used on the battleship. (The other was red lake pigment.) Fortunately, Stockholm shipyard’s records from 1605–1640 had been preserved. Records of paint purchases from the time of the Vasa’s construction helped the investigators deduce whether it was possible for a particular paint to show up in their analyses. It turned out that the artists who created the Vasa sculptures had used the same paints that easel artists of the time, like Rembrandt and Rubens, were using. Tångeberg and Plahter painstakingly began to work out how the sculptures on the Vasa must have originally looked (Endeavour 2000, 24, 147–151). The most important thing they discovered was that the human figures were painted in a flesh color, created by mixing lead white with red iron oxide pigment or vermilion. “The common [perception] was the sculptures were all gilded so the faces and [bodies] were in gold. When I made comparisons with the objects in the churches and the ship paintings, I came to the conclusion that they must have been painted in flesh colors,” explains Tångeberg. Another conclusion the investigators drew was that some of the sculptures on the Vasa had been stored before being fitted onto the battleship. “There were cracks [in the sculptures] and colors in the cracks. It must have been original colors because the Vasa was painted only once,” says Tångeberg. “My theory is that [the sculptures] had been stored for some time. If you think about it, there were 500 sculptures, so it must have taken several years to carve and paint them.” The discovery of paints on the Vasa is significant. “It isn’t only important for the knowledge [of] how ships looked,” states Tångeberg. The Vasa is the only 17th-century European structure with so many wooden sculptures in one place—there isn’t an equivalent church arch or decoration that can compete with the size of the battleship. The Vasa “isn’t only important as a ship, but it’s also important for art history,” says Tångeberg. a — Rajendrani Mukhopadhyay
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