Light gives light, to light discover--"Ad infinitum." St. Louis, (Missouri Territory,) North America, April 10, A.D. 1818 : To all the world! I declare the earth is hollow, and habitable within ... I pledge my life in support of this truth, and am ready to explore the hollow, if the world will support and aid me in the undertaking. - Symmes, John Cleves, ([publisher not identified],, 1818)