PRINCIPLES AND METHODS OF PALAEONTOLOGY'. 365 



Importaut as it is, however, to tlie welfare aucl prosperitj' of the 

 couutry that an accnrato record sliouki exist of the composition of its 

 share of the earth's crust, whence the miner, the metalkirgist, and the 

 mineralogist extract so many products of the utmost value to man, and, 

 indeed, indispensable to the maintenance of his present complex state 

 of civilization to suppose that this immediate and so-called '* practical" 

 object of the collection is the only, or even the most important, end 

 that it subserves, would be as great an error as that of the barbarous 

 Oriental, Avho sees nothing but a convenient stone quarry in those mas- 

 sive pyramids, on whose walls the instructed Eastern traveler reads the 

 history of an ancient world, and learns the more, the more knowledge 

 and capacity he brings to the inquiry. In truth, the history, not merely 

 of one but of a series of ancient worlds, is written upon tke rocks which 

 compose the solid coating- of the globe in signs the meaning of which is 

 decipherable with far more ease and certainty than that of hieroglyphic 

 or cuneiform inscriptions ; or we might say that, as it is the custom in 

 these times to deposit the coins and medals of the age under the founda- 

 tion stones of a building-, so the Great Artificer has, as he laid each 

 course of stone in the world's foundations, deposited coins and medals ol 

 His striking-, the remains of the then existing system of organic life, 

 the bones and shells of the contemporaneous living beings. 



But a history in an unknown tongue can be profitable only to those 

 who will take the trouble to acqmre a knowledge of the construction of 

 the language, and of the signification of its words and signs. Now, 

 natural history, or the science of the structure and habits of living 

 beings, is the grammar and dictionary of the language of fossils. To 

 understand all that fossils teach, natural history must have been the 

 study of a life; but a clear comprehension and careful recollection of a 

 few of its simpler principles will be sufficient to enable a person of in- 

 telligence, unversed in science, to apprehend the wider bearings of the 

 collection. To aiford this assistance is the sole object of the pres- 

 ent explanatory preface. It is intended to awaken even a casual visitor 

 to a sense of the profoundly interesting problems which the collection 

 forces upon our consideration ; to enable him to comprehend how it is 

 that the naturalist reads here, as plainly as if it were stated in to-daj's 

 paper, and with considerably more faith than he would place in any 

 mere human affirmation, that the earth has undergone a great series of 

 changes, stretching- over enormous periods of time ; that its living popu- 

 lation has not always been what it is now, but that the present kinds of 

 animals and plants have been preceded by others widely ditfering- from 

 them, and these by others, and so on, for an indefinite series of altera- 

 tions ; that these changes have been accompanied hj constant altera- 

 tions in climate and in the level of the land and sea ; finally, that the 

 period of time of which these records furnish the history is inconceiva- 

 bly immense. 



These are weighty articles of belief, and nothing- can seem, at first, to 

 be less likely than that the accumulation of oddly marked and shaped 

 stones, which are ^^sible on the shelves around, should contain abund- 

 ant evidence of their validity and truth ; but so it is. How it is, will 

 be rendered clear by what follows. 



II. — Brief exposition of those principles of natural history 



WHICH are op the MOST IMPORTANCE TO 'THE UNDERSTANDING 

 OF FOSSILS. 



It has been stated that natural history is the key to palaeontology, and 

 hence, before attempting to learn the meaning of fossils, it is necessary 



