CAMBRIDGE, ENGLAND—Live Science reports that scientists at the University of Cambridge used near-infrared imaging to examine a dark spot on a page in an illustrated Christian prayer book commissioned in 1431 by Yolande of Aragon, the duchess of Anjou. The duchess gave the prayer book to her daughter, Yolande of Anjou, who married Duke Francis I of Brittany in 1431. The young woman died in 1440. The study revealed that an image of Yolande of Anjou kneeling in prayer before the Virgin Mary had been concealed by a later painting of the duke’s second wife, Isabella Steward of Scotland, who is also depicted kneeling in prayer before the Madonna. The fourth-century saint, Catherine of Alexandria, is shown beside Isabella. “At the death of his first wife, Francis may have taken control of the prayer book and ordered it to be customized to best suit Isabella,” said Suzanne Reynolds, curator of manuscripts at the university’s Fitzwilliam Museum. “It is possible Isabella had some input. For example, the inclusion of St. Catherine who was not there before indicates that Isabella may have had a special devotion to this saint.” Isabella’s royal coat of arms was also painted on many of the book’s pages, she added. To read about pages from a fifteenth-century prayer book that were found in the eaves of the home of a prominent English family, go to "Artifact."