Tower Falls and and sulphur mountain, Yellowstone National Park. Colour lithograph by L. Prang after T. Moran, 1874. https://www.rawpixel.com/image/13968426/image-cloud-plant-personFree Image from public domain licenseGreat Falls of Snake River, Idaho territory / TM ; Prang's American Chromo., L. Prang & Co., publisher https://www.rawpixel.com/image/7689123/image-thomas-moran-snake-prangFree Image from public domain licenseTower Falls and Sulphur Mountain, Yellowstone / TM ; Prang's American Chromo., L. Prang & Co., publisher https://www.rawpixel.com/image/7690640/image-thomas-moran-prang-waterfall-illustrationFree Image from public domain license