Hot Springs of the Yellowstone

Mineral terraces spill across the foreground in butter yellow and rust orange, each shallow pool holding a slick of pale blue water. Steam drifts up and swallows the middle distance, so the mountain behind it looks like it is floating, and a rainbow leans in from the right where sunlight catches the vapor. Thomas Moran painted this in 1872, working from sketches and watercolors he made the previous summer in what is now Yellowstone National Park. The bumpy, cauliflower-like crusts at the bottom edge are travertine, limestone left behind as hot water cools and evaporates, building up layer by layer over centuries.

Moran had traveled west in 1871 with the Hayden Geological Survey, the first official expedition into the region, and he was thirty-four and had never really camped before. What he brought back mattered enormously: his watercolors were passed around Congress alongside William Henry Jackson's photographs, and in March 1872 Yellowstone became the world's first national park. Moran was so linked to the place that he began signing his work with a monogram that read T-Y-M, the Y standing for Yellowstone. His style belongs to the Hudson River School tradition, where American scenery is painted with a touch of reverence, though here the color does a lot of the work. The oranges look almost artificial, which is exactly what made people back east doubt the reports coming out of the territory.