The Legacy Left Behind by Percival Lowell, Part I

Upon hearing about Schiaparelli’s telescopic observations of Mars, Lowell financed his own observatory at Flagstaff, Arizona in 1894. In less than a year of observations, Lowell began to make wild speculations about what he had observed. Lowell claimed that the dark areas on the surface of Mars are deserts, and the canals are built by extremely intelligent beings to irrigate the desert planet with water from the polar caps. He theorized that Mars was once like the Earth but since had lost its oceans; so in order to preserve life on their dying planet, the Martians built this vast irrigation system.

http://www.space.com/scienceastronomy/050926_mars_lore.html