Samuel Birley Rowbotham

Samuel Birley Rowbotham (; 1816 – 23 December 1884, in London) was an English inventor, writer, utopian socialist and flat Earther who wrote Zetetic Astronomy: Earth Not a Globe under the pseudonym Parallax. His work was originally published as a 16-page pamphlet (1849), and later expanded into a book (1865).

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 its surface.

Rowbotham's work is generally credited with the modern revival of belief in a flat Earth.