Page:Is Mars habitable - Wallace 1907.djvu/16

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TABLE OF CONTENTS.

CHAPTER I.

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Mars the only planet the surface of which is distinctly visible—Early observation of the snow-caps and seas—The 'canals' seen by Schiaparelli in 1877—Double canals first seen in 1881—Round spots at intersection of canals seen by Pickering in 1892—Confirmed by Lowell in 1894—Changes of colour seen in 1892 and 1894—Existence of seas doubted by Pickering and Barnard in 1894.

CHAPTER II.

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.