Percival Lawrence Lowell (1855-1916) was an American businessman, author, mathematician, and astronomer who fueled speculation that there were canals on Mars and founded the Lowell Observatory in Flagstaff, Arizona. For fifteen years Lowell studied Mars extensively, and made intricate drawings of the surface markings as he perceived them. Lowell published his views in three books: Mars (1895), Mars and Its Canals (1906), and Mars As the Abode of Life (1908). With these writings, Lowell more than anyone else popularized the long-held belief that these markings showed that Mars sustained intelligent life forms.