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state of gaseous fusion, is a paradox. There are no indications where the continents and mountains were stationed, from the ruins of which it is held the strata were formed. Had there been such continents and mountains as the hypothesis implies, they must have been of such an elevation as to have been protected by congelation from being disintegrated and transported to the sea by the action of water. Had they been depressed into a temperate region, still no springs could have emerged from their surface, nor permanent streams and rivers descended from them to the sea. Had they been disintegrated and traversed by streams and rivers, they could never have borne more than an inconsiderable portion of their detritus to the ocean. Had their detritus been transported to the sea, it could not have been transformed into sand, gravel, and pebbles: it could not have been spread over the bed of the ocean: it could not have been assorted according to the materials of which it consists, and formed into separate layers of sandstone, limestone, and shale. There is not one of these processes through which the theory represents the materials of the strata as having passed, that is not in contradiction to the laws of the physical world, and an infinite impossibility. The demonstration is absolute, therefore, that the strata cannot have been formed by these processes, and that the whole theory is groundless and mistaken. The inference accordingly that is founded on it of the vast age of the world, is equally unphilosophical and false.

QUESTIONS.

Suppose that chemical agents could have acted on those continents, and produced a rapid disintegration, is it credible that it could have gone to the extent the theory assumes? What are the two conditions which that implies? Is either of them consistent with the laws of matter? If those continents became covered with a soil, is it not as incredible that streams should have borne it all to the ocean, as it is that the streams of the present continents should bear all the earth and gravel of the regions from which they run to the sea? Is there any reason to suppose that a millionth part of the detritus of the Andes ever reaches the ocean? Does it not, with the exception of comparatively few particles, lodge near the foot of the ranges from which it is disintegrated? Does not all but the merest fraction of the debris of the Rocky Mountains remain where, or near where, it first falls? Could the other condition which they assume have been realized? Give the first reason that it could not. Give the second reason. What does Humboldt state in regard to the inadequacy of rivers to wear away the rocks over which they pass? Is it clear then that continents of granite could never have been converted into sand and dust, and transported to the ocean by the chemical and mechanical agents that are now acting on the earth's surface?

But could those granite continents have been reduced to dust, would they have furnished the various substances of which the strata consist? Of what is granite composed? What are the proportions in which these elements exist in it? What are the only strata that might have been formed out of those elements? What other strata are there of which they could not have furnished the principal ingredient? What proportion of the strata then must have been derived from some other source? By what formation is this exemplified in this country? Is limestone spread over vast regions? What aggregate thickness do its several beds in a single group sometimes attain? Are geologists aware that these immense deposits of lime cannot be accounted for on their theory? What other substances are there that enter into the composition of the strata, that cannot have been derived from granite? Do these facts confute their theory? Does it fail also to account for those strata, such as sandstone, that consist of substances that exist in granite? State the reason. What is the difference of the form of quartz in granite and sandstone? Is the assumption of geologists that the crystals of granite have been changed into the granules of sandstone, admissible? What is the first reason against it? What is the second? Can such a change have been produced by chemical agents? Can it by mechanical forces? What other classes of strata are there that cannot, for the same reason, have been derived from granite? Does the theory then fail to account for all but an inconsiderable portion of the strata?

Suppose, however, those difficulties were overcome, and that rivers could have borne down a large quantity of detritus to the sea ; could they have spread it over vast areas of the bottom of the ocean? Do the great rivers of the present earth carry the earthy matter with which they are charged more than a short distance into the sea? Is it not a law that of the matter borne down by a river, that which is of greater specific gravity than the water itself, sinks as soon as the force of the current ceases to bear it forward? Is it not certain that no river of the globe continues its current more than a few miles after it enters the ocean? Is it not impossible then that rivers can have diffused their detritus over the whole bottom of the ocean? Are not the strata, however, spread over vast areas? Give examples. What can be more clear than that these strata can never have been formed over such immense spaces by the agency of rivers? What is Sir C. Lyell's theory of the agency of rivers in the formation of strata? Could a river ever by that process form a layer of pebbles or sand over more than a very limited space? State the reason that it could not. What is his theory in respect to a change of the points at which rivers enter the ocean? Could such changes ever enable them to spread their earthy and vegetable matter over the whole bottom of a spacious sea?

And finally, is not the distribution of the chief elements of the strata into separate layers inexplicable on their theory? What are those elements? How are the different earthy elements borne down by rivers usually deposited? Are they sorted, or thrown down promiscuously? What is the manner in which the elements of the strata were distributed? Specify the elements of the leading groups. Recapitulate these various proofs of the error of the theory.

CHAPTER XI.

False Theories of Geologists respecting the Formation of the Strata.

That branch of their theory which relates to the sources whence the materials of the strata were derived, and the agents by which they were conveyed to their place of deposition being thus confuted, the next inquiry respects their other great postulate, that the original formation of the strata and the modifications to which they have been subjected, were the work of the chemical and mechanical forces that are now producing changes in the earth's surface, and were the result of agencies, in the main, of only their present measure of intensity. If this postulate, on which they found the most of their reasonings, is shown to be gratuitously assumed also, inconsistent with the most important characteristics of the strata, and in contravention of the principles of the science, then the second main ground of their inference of the great age of the world will also be overthrown: and such is undoubtedly its character.

As it is apparent from the preceding discussion that streams and rivers have had no important agency in

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