INTRODUCTION TO THE PRESENT EDITION. Shortly after the publication of the first Edition of the Comparative Estimate, several very important works on Geology appeared in quick succession before the world; viz. The first Volume of the Geology of England and Wales, with the Introduction of the Rev. W. D. CoNY- brake. Mr. Professor Buckland’s Reliquiae Diluvianae. M. Cuvier’s Ossemens Fossiles. New Edition. The Translation of M. Humboldt’s Geognostical Essay on the Superposition of Rocks in both Hemispheres. The Edinburgh and Quarterly Reviews of the Re- liquia Diluviance. To these may be added, the Geological Disquisition introduced by the Rev. G. S. Faber into his Treatise on the Three Dispensations. Also, the reviews of this present Work, in the Eclectic Review, in the Journal of Science, and lastly, in the British Critic. The important matters which the former of those works contained, could not therefore have been noticed in the first edition of this treatise ; and consequently, in
