“Vermeer is regarded as a national hero by the Dutch. The matter was investigated and the painting traced to Han Van Meegeren, a modern Dutch painter who had only a fair talent. When Van Meegeren realized he might be charged with treason by the Dutch for selling a Vermeer to the Nazis, he confessed that he had painted it himself. He also confessed that he had painted other forgeries that fooled some of the experts and were sold for a lot of money. “Many people, however, thought Van Meegeren was only lying to save himself from the charge of treason, and the whole thing had to be decided by a committee of scientific art experts appointed by a court of law. Using the methods that were then available, the experts showed that Van Meegeren had done a remarkable job of forgery and they were convinced that he had been telling the truth about painting those pictures. “At the time, the important ways the experts used to examine a painting included studying the work with X rays, which could show another painting underneath, analyzing the pigments (or coloring materials) used in the paint, and examining the painting for certain signs of old age. [Illustration: _Han Van Meegeren listens to the evidence at his trial in Amsterdam. In the background is “The Blessing of Jacob”, which was sold in 1942 as the work of Vermeer._] [Illustration: _An authentic Pieter de Hooch work, “The Card Players”, painted in the 17th century._] [Illustration: _A forgery of a Pieter de Hooch picture painted in the 20th century by Han Van Meegeren._] [Illustration: _“Head of Christ” by Van Meegeren._] “Van Meegeren was well acquainted with these methods. He scraped the paint from old paintings that weren’t worth much just to get the canvas and tried to use pigments that Vermeer would have used. He knew that old paint was very, very hard and impossible to dissolve; so he cleverly mixed a chemical (phenolformaldehyde) into his paint, and this hardened into Bakelite when he heated the finished painting in an oven. “For some of the paintings, Van Meegeren became careless and the experts did find traces of a modern pigment (cobalt blue) in the paint. They also found the Bakelite. For one or more paintings, Van Meegeren did so well that, in spite of all this evidence, a few people still weren’t convinced that these paintings were painted by Van Meegeren and not by Vermeer.” Bill, who by this time was bursting with questions, interrupted, “You mean they still aren’t sure about some of those paintings after 25 years? Aren’t there better ways of telling whether a painting is genuine or not? You’re a scientist. Can’t scientists like you do something about it now?” “Yes, recently a method was developed to settle just such a question. It’s based on measurements of natural radioactivity in one pigment that all artists used hundreds of years ago. And the method was applied to some of the Van Meegeren paintings including the best one of them all.”