From New York Times:
If you believe, as Maurizio Seracini does, that Leonardo da Vinci’s greatest painting is hidden inside a wall in Florence’s city hall, then there are two essential techniques for finding it. As usual, Leonardo anticipated both of them.
First, concentrate on scientific gadgetry. After spotting what seemed to be a clue to Leonardo’s painting left by another 16th-century artist, Dr. Seracini led an international team of scientists in mapping every millimeter of the wall and surrounding room with lasers, radar, ultraviolet light and infrared cameras. Once they identified the likely hiding place, they developed devices to detect the painting by firing neutrons into the wall.
“Leonardo would love to see how much science is being used to look for his most celebrated masterpiece,” Dr. Seracini said, gazing up at the wall where he hopes the painting can be found, and then retrieved intact. “I can imagine him being fascinated with all this high-tech gear we’re going to set up.”
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