He took a little time to learn his trade, running away from a lecture in Blackburn when he couldn't explain why the hulls of ships disappeared before their masts when sailing out to sea. After measuring a lack of curvature on the long straight drainage ditches of the Bedford Levels in his first Bedford Level experiment, he was convinced of the flatness of the Earth and began to lecture on the topic.

Rowbotham started out as an organiser of an Owenite community at Manea in The Fens, where he formulated his ideas about the Earth. Rowbotham's method, which he called zetetic astronomy, models the Earth as a flat disc centered at the North Pole and bounded along its perimeter by a wall of ice, with the Sun, Moon, planets, and stars moving only several thousand miles above the surface of Earth. His work was originally published as a 16-page pamphlet (1849), and later expanded into a book (1865).

Samuel Birley Rowbotham ( / ˈ r oʊ b ɒ t ə m/ 1816 – 23 December 1884, in London) was an English inventor, writer and utopian socialist who wrote Zetetic Astronomy: Earth Not a Globe under the pseudonym Parallax.

Who invented flat earth theory