TRANSCRIBER’S NOTE Italic text is denoted by _underscores_. Footnote anchors are denoted by [number], and the footnotes have been placed at the end of the book. A superscript is denoted by ^x or ^{xx}, for example Edin^r or 1^{st}. Basic fractions are displayed as ½ ⅓ ¼ etc; other fractions are shown in the form a/b, for example 9/10. Some minor changes to the text are noted at the end of the book. ESSAY ON THE THEORY OF THE EARTH. [Illustration: FRONTISPIECE _Page 518_ _W. H. Lizars Sc._ VERTICAL SECTION OF THE CAVERN AT GAYLENREUTH IN FRANCONIA] ESSAY ON THE THEORY OF THE EARTH. BY BARON G. CUVIER, PERPETUAL SECRETARY OF THE FRENCH INSTITUTE, PROFESSOR AND ADMINISTRATOR OF THE MUSEUM OF NATURAL HISTORY, _&c. &c._ WITH GEOLOGICAL ILLUSTRATIONS, BY PROFESSOR JAMESON. FIFTH EDITION, TRANSLATED FROM THE LAST FRENCH EDITION, WITH NUMEROUS ADDITIONS BY THE AUTHOR AND TRANSLATOR. WILLIAM BLACKWOOD, EDINBURGH; AND T. CADELL, STRAND, LONDON. MDCCCXXVII. _Printed by P. Neill._ PREFACE TO THE FIFTH EDITION. Geology, now deservedly one of the most popular and attractive of the physical sciences, was, not many years ago, held in little estimation; and even at present, there are not wanting some who do not hesitate to maintain, that it is a mere tissue of ill observed phenomena, and of hypotheses of boundless extravagance. The work of CUVIER now laid before the public, contains in itself not only a complete answer to these ignorant imputations, but also demonstrates the accuracy, extent, and importance of many of the facts and reasonings of this delightful branch of Natural History. Can it be maintained of a science, which requires for its successful prosecution an intimate acquaintance with Chemistry, Natural Philosophy and Astronomy,--with the details and views of Zoology, Botany, and Mineralogy, and which connects these different departments of knowledge in a most interesting and striking manner,--that it is of no value? Can it be maintained of Geology, which discloses to us the history of the first origin of organic beings, and traces their gradual development from the monade to man himself,--which enumerates and describes the changes that plants, animals, and minerals--the atmosphere, and the waters of the globe--have undergone from the earliest geological periods up to our own time, and which even instructs us in the earliest history of the human species,--that it offers no gratification to the philosopher? Can even those who estimate the value of science, not by intellectual desires, but by practical advantages, deny the importance of Geology, certainly one of the foundations of agriculture, and which enables us to search out materials for numberless important economical purposes?