THE EVOLUTION OF
WORLDS
BY
PERCIVAL LOWELL, A.B., LL.D.
AUTHOR Of "MARS AND ITS CANALS," "MARS AS THE
ABODE OF LIFE," ETC.
DIRECTOR OF THE OBSERVATORY AT FLAGSTAFF, ARIZONA; NON-RESIDENT PROFESSOR
OF ASTRONOMY AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY; FELLOW OF
THE AMERICAN ACADEMY OF ARTS AND SCIENCES; MEMBRE DE LA SOCIÉTÉ
ASTRONOMIQUE DE FRANCE; MEMBER OF THE ASTRONOMICAL AND ASTRO-
PHYSICAL SOCIETY OF AMERICA; MITGLIED DER ASTRONOMISCHE GE-
SELLSCHAFT; MEMBRE DE LA SOCIÉTÉ BELGE D'ASTRONOMIE;
HONORARY MEMBER OF THE SOCIEDAD ASTRONOMICA DE MEX-
ICO; JANSSEN MEDALLIST OF THE SOCIÉTÉ ASTRONOMIQUE DE
FRANCE, 1904, FOR RESEARCHES ON MARS; MEDALLIST
OF THE SOCIEDAD ASTRONOMICA DE MEXICO
FOR STUDIES ON MARS, 1908
ILLUSTRATED
New York
THE MACMILLAN COMPANY
1910
All rights reserved