WORLD-LIFE COMPARATIVE GEOLOGY. - Geology in framing its conclnsione is compelled to take into account the teachings of other sciences-SIR WILLIAX THOEXSON. La geologie suivie sous ce point de vlie qoi la rattache B IAstrouomie pourra, snr beancoup dobjets, en acqlidrir In precision et la certitude.-LAPLACE. Ewig zerstUrt, es erzeugt eich ewig die dreheude Schcpfung, Und ein stilles Gesetz lenkt der Verwandlungen S.-SCHILLER. CHICAGO S. C. GRIGGS AND COMPA4NY. 1 8 8 3 . COPYRIGHT, BY S. C. GRIGOS AND COMPANY. HIS PUPILS IN THE UNIVERSIIY OF MICHIGAN, THIS VOLUJIE IS, WITH PROFOUXD COSSIDERATION, r AFFECTIONATELY Ih-SCRIBED THE AUTHOR.-- PREFACE. -- THE reader will find in the following pages a thoughtful view of the processes of world formation, world growth and world decadence. I have gathered together here many of the iliiportant facts observed in the constitntion and course of natnre, and hare endearored to weave them into a system by the connecting threads of scientific inference. I have aimed to incorporate the soundest and latest views published on the variolls branohes of the snbject and have yet felt constrained, in so wide a field, and so unesplored in some of its nooks, to interpose my own conclusions in solne cases where, perhaps, due diffidence should have restrained my pen. Inevitably the whole discussion is conducted from the standpoint of nebular cosmogony. This, as will be seen, has shaped the views presented on the acc rn ilatioof nt he materials for world formation, on the evolutions of nebulae, stars and planets, on the all-important influence of tidal action in cosmic history, and on the grand cycle of cosmic existence. Appropriately the treatment ends with s historical sketch of the progress of opinion toward the lofty and inspiring generalization which the work at, tempts to set forth. The motives which have prompted to the preparation of the work are four-fold . 1. I felt desirous that the general reader should be able to find within reach some simple, yet complete and connected, account of the development of the world and the system of material things to which we belong. Many of tlre grandest conceptions of modern science fall within this range. Many of the marked advances of tnodern investigation have contributed to the enlargement of our view in this field. Yet there is no work in the English language, if, indeed, in any language, bringing into one connected course of disclission all the questions properly incident to the activities of world v vi PREFACE. life. Different persons have ably investigated different branches of the general theme, as the reader will learn in the sequel, but no one has brought together and put in the form of popular statement the chief results of so diversified-a range of researches. JIany thousands of intelligent listeners have testified their appreciation of the expositions offered during fifteen years past from the popular platforln but these expositiol sh ave been necessarily dexriptive and superficial, while many questions and many difficulties raised by the hearer had to be left unanswered. Here the speaker sits down to a sober talk with t. hose who wish to listen further. I hope, therefore, the present work will find a weleome among tbe nultitndesw ho have caught mere glinlpses of the great doctrine, as well ns the large class of readers in general who require something Inore substnntinl than our popular, fictitious tales of society. 2. I desired to offer the reader a portrayal of the grand system of the universe, and leave him with a profonnd impression of the omnipresence and supremaey of One Intelligence. The unity and interdependence of all parts of i5... --This text refers to an alternate Paperback edition.