CHADDS FORD, PA.- This summer, the Brandywine River Museum presents works by Andrew Wyeth spanning seven decades, including several that are rarely on public view and one that has never been seen in public. This current installation will remain on view through September 19, 2011. Wyeth’s technical mastery and intense focus on people and places he knew well is obvious in superb watercolors and egg tempera paintings that show his deep feeling for the visual and tactile world and his life-long endeavor to recreate his experiences through art. Visitors to the gallery will see two early works by Wyeth painted in his 20s: Apples on a Bough, a study for Before Picking (1942), and Blackberry Branch, a study for Blackberry Picker (1943). Both are dry brush watercolors on paper. Wyeth’s feelings for his wife, Betsy, is clear in A Feather in Her Cap (1987), a portrait of Betsy at their millhouse in Chadds Ford, and in May Bask