Germany. Upon his discharge from the army, he became the acting curator of graphic arts at Princeton University. After Van Devanter worked a year at Princeton, his former mentor at Yale University, head librarian Jim Babb, recommended him for a job as the personal curator for Paul Mellon. Mellon's father, Andrew W. Mellon, a multimillionaire Pittsburgh businessman and a former U.S. Treasury Secretary, had established and—in effect—had donated the National Gallery of Art in Washington to the people of the United States. His son Paul carried on his father's work as a philanthropist. At age 27, Van Devanter became Mellon's chief of staff for art and rare books. He did everything from working with art dealers to buying books and entertaining Mellon's guests. “Everything I know is based on Paul Mellon and the great experiences I had traveling around the world and finding treasures,” he said. Together they virtually cornered the market on the works of William Blake, the English poet, painter, and printmaker. Facsimiles were created from Blake's work and many of them wound up in American universities. When Van Devanter learned that Sotheby's might sell some of the works of John Locke, he flew to England, rented a bike, and chased down the Oxford librarian on his morning bicycle ride to work, to seek his cooperation. He also worked with Paul Mellon to buy and place the Vinland Map at Yale. The still controversial map, which was found in Spain, purportedly showed that the Norse had discovered America before Columbus. By the end of his 17-years as a Mellon associate, Van Devanter had helped assemble and catalog one of the greatest collections of Americana in the United States. The collection was, on Mellon's instructions, divided among two Virginia institutions and Yale upon his death. After leaving Paul Mellon, Van Devanter worked two years for a leading Washington D.C. art and antiques dealer, appraising paintings and books—and then struck out on his own. His reputation soon spread and he began to consult with museums and universities across America, including major institutions such as the Smithsonian and the Library of Congress. He proved to have a natural touch with the rich and poor, the celebrated or the unknown. Far from being an art snob, he treated everyone with equal respect, no matter the value of the treasures they brought for his appraisal. A Washington Post article in 2003 caught his