Is Mars habitable? A critical examination of Professor Percival Lowell's book "Mars and its canals," with an alternative explanation

by Alfred Russel Wallace

CHAPTER II.

MR. LOWELL'S DISCOVERIES AND THEORIES,
—Observatory at Flagstaff, Arizona
—Illustrated book on his observations of
Mars
—Volume on Mars and its canals, 1906
—Non-natural features
—The canals as irrigation works of an intelligent
race
—A challenge to the thinking world
—The canals as described and mapped by Mr. Lowell
—The double canals
—Dimensions of the canals
—They cross the supposed seas
—Circular black spots termed oases
—An interesting volume.