"There is a somewhat extensive cave in the north portion of the sandstone ridge that forms the entrance to the 'Garden of the Gods.' It is caused by the washing away of a soft layer, about three feet thick, by a little stream of water that trickles down from the summit of the ridge."Fortunately, a late-joining member of the survey party was an artist at heart. This was William Henry Jackson, whose photographs and paintings have since become national treasures. Jackson was working out of his photgraphy shop in Omaha when he was first contacted by Professor F.V. Hayden. "Would he consider joining the survey party as official photographer?" Would he, indeed! Jackson immediately bade farewell to his wife, Mollie, and headed west. He reached Colorado Territory in the fall of 1870. For several weeks he was a familiar sight around the Pikes Peak region with his burro-load of heavy photographic equipment, glass plates and darkroom tent.
While taking photgraphs in the Garden of the Gods, Jackson seems to have entered the cavern so recently described by other members of the survey team. Inscribed on the walls of Spaulding's Cavern is the name "W. Jackson." Directly underneath the name is the date "1870."
A picture of this name was taken by a photographer for the Colorado Springs Gazette and Telegraph when the entrance to the cavern was re-disovered in 1935. The photographer was aiming his camera at the "Mrs. Lou Frost" name direcly above, and inadvertantly included the Jackson name.
Whether or not this "W. Jackson 1870" name was actually carved by William Jackson himself may never be known for certain. What is certain is that Jackson did have the opportunity to do so: he was present in the Garden of the Gods; the year was 1870; and he was taking photographs for the Hayden Survey.
SOURCE: First, Second & Third Annual Reports of the United States Geological Survey of the Territories for the Years
1867, 1868, 1869. Published in 1873.