On vacation last week in Upstate New York, I climbed the gorge at Watkins Glen State Park, spotting many pools that brought to mind John Twachtman’s The Emerald Pool (ca. 1895). Of course, Twachtman’s pool was likely a hot spring and surrounded by the open and dry dirt ground of Yellowstone Park and not the dark, wet stone and lush greenery of the glen. But the beautiful emerald effect of deep pooling water immediately brought this painting to my mind. Duncan Phillips was a great admirer of Twachtman, hanging The Emerald Pool in an esteemed spot alongside Monet for many years. And Marjorie Phillips recorded in her book that, after a visit to the Phillips in 1926, Pierre Bonnard said that it was his favorite American painting.