A term introduced by Percival Lowell
in 1895 to describe dark, round features on the surface of Mars
which he claimed lay at the major intersections of a Martian canal network.
These features had been referred to as "lakes" by William Henry Pickering
in 1892. Lowell, however, believed they were extensive regions of vegetation
irrigated by canal-borne polar meltwater. They were an important feature
of his theory concerning an extant Martian civilization.
|Percival Lowell's 1909 map of Mars showing canals
as thin lines and "oases" as round blobs at the major intersections
canals on Mars
vegetation on Mars