The painters who came to be known as the Hudson River School--Thomas Cole, Asher B. Durand, Frederic Edwin Church, Jasper Cropsey, Sanford Robinson Gifford, and others--found inspiration in our young country's natural wonders and were the first to paint many of its still-wild vistas. As America was settled and the wilderness receded, their successors--most notably Albert Bierstadt and Thomas Moran--carried their quest for the sublime to the Far West,...