'Scenes in Mammoth Cave', 1874. Tourists visit limestone caverns in Kentucky, USA, the longest cave system known in the world: 'Shelby's Dome & Bottomless pit; Grand Crossing; Mouth of the Cave; Mammoth Dome; Napoleon's Dome; Gothic Chapel'. '...in Shelby's Dome...The height seems limitless, and the eye traces on the walls innumerable scrolls, panels, and fanciful projections of the most varied design and beauty. Under the dome is the celebrated Bottomless Pit, which has a depth of one hundred and seventy-five feet...the Mammoth Dome, which appears much over a hundred feet high, with its magnificent walls of sheer rock'. From "Picturesque America; or, The Land We Live In, A Delineation by Pen and Pencil of the Mountains, Rivers, Lakes...with Illustrations on Steel and Wood by Eminent American Artists" Vol. II, edited by William Cullen Bryant. [D. Appleton and Company, New York, 1874]