Every part of the earth's surface presents unequivocal proofs that the elevation of the bed of the ocean in some places, and the subsidence of the dr… - Gideon Mantell

Although we may not be able to mark the precise boundary beyond which organic beings do not appear, it is certain that in all geological epochs, subsequent, at least, to that of the primary rocks, animals and plants have existed in successive families; they have been created, have lived their day, and by the operation of physical causes, have perished; while new races have been called into being, and in their turn have ceased to be, in order to give room to other families, requiring, perhaps, a different climate, and a new order of things.

In the prosecution of these researches... extraneous fossils were no longer regarded merely as subjects of natural history, but as memorials of revolutions which have swept over the face of the earth, in ages antecedent to all human record and tradition.

A work upon the plan originally contemplated by the Author seems still to be required, to initiate the young and uninstructed in the study of those MEDALS 0F CREATION—those electrotypes of nature—the mineralized remains of the plants and animals which successively flourished in the earlier ages of our planet, in periods incalculably remote, and long antecedent to all human history and tradition. With this conviction the present volumes are offered... as a guide for the Student and the Amateur Collector of fossil remains; for the intelligent Observer who may desire to possess a general knowledge of the subject, without intending to pursue Geology as a science; and for the Tourist who may wish, in the course of his travels, to employ profitably a leisure hour in quest of those interesting memorials of the ancient physical revolutions of our globe, which he will find everywhere presented to his observation.