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General Nature of the Formations on the Earth.—Origin
and Progress of Secondary Formations.--Causes of Stratification in Secondary Rocks.—Such Deposits become gradually Mineralized.-Calcareous Formations.-Salt Deposits.-Proof of Granite not being an Aqueous Deposit.- Secondary Formations now in Progress in the Bed of the Ocean.
The active researches of geologists into the existing phenomena on the surface of the earth, have led to the following conclusions with respect to mineral bodies.
“ PRIMITIVE Rocks
“ Consist only of crystalline formations;
They contain no organic remains;
They are found below all other rocks; " And they rise from the base, through all other rocks,
forming the summits of the most lofty mountains.
" TRANSITION AND Flerz,
(or Secondary Rocks,) “ Consist partly of crystalline, partly of mechanical
deposits; They contain organic remains of sea shells; “ And are never found under primitive rocks.
" ALLUVIAL DEPOSITS “ Consist of mechanical deposits ;
They result from the ruin of rocks;
“ bones of quadrupeds,” and of the human race; " And they are found above all the other rocks." *
Thus far, the chaotic and the Mosaic geologies coincide; the facts are self-evident, and within the reach of every one who will take the trouble to examine them. But when the causes by which these facts have been produced, come under consideration, the two geologies separate; the one following the path which history has marked out, and which reason can comprehend, leading at every step towards the light of truth : the other, under a variety of leaders, plunges into the dark and devious mazes of hypothesis, rejects the guidance of history, and is led, more and more, into obscurity and error. There is no possible way of clearing this labyrinth, and of gaining the desired end, but by retracing our steps, and taking advantage of the clue which history affords us. But in doing this, we must keep constantly in mind the difficulties from which we have escaped; and the impossibility we have experienced of tracing primitive effects to secondary causes. Truth and Reason acknowledge but one Primitive Cause; and that is, an Almighty, though to us, Incomprehensible CREATOR.
* Phillips's Geology.
Having found the arguments in favour of secondary causes, or the mere laws of nature, as they are called, totally insufficient to account satisfactorily to our reason, for the first formation of crystallized mineral bodies, any more than for the first formation of animal or vegetable bodies; we come to the unavoidable conclusion that they were all the creative work of an Almighty hand. But as it is evident, that this creation, as soon as completed, was submitted to certain laws, by some of which a constant succession of decay, and re-formation, was to be kept up in the mineral world, at least as far as regards the mere surface of the earth; it may be considered quite within the scope of our reason to examine these laws; and to account for these secondary effects, by secondary causes.
We find, then, that it is one constant law of the Creator, that the action of the atmosphere shall decompose, or break up, the mineral bodies exposed to its influence. We find another, called the law of gravity, by which the waters of the earth, in seeking their own level, are hurried from the highest mountains to the sea ; carrying along with them abundance of mineral matter in the shape of sand, mud, and gravel. We find a third law, by which the waters of the ocean are kept in constant agitation; and the mineral matter imported by the rivers, is arranged in classes, according to the weight and volume of its parts, and distributed over the sea bed in various directions, and in various quantities, according to the nature of the currents which remove it.*
* This law of arrangement, which is founded on the law of gravity, may be looked upon as the great agent in distinct stratification. And as this law could not be in force without the lateral movement kept up by the currents of the ocean, we cannot look for its effects in situations where such constant action and re-action of currents do not exist. Thus we never can expect to find the secondary formations of fresh water lakes, however extensive, in the same stratified arrangement as in the bed of the sea. Whatever sand, mud, gravel, or rock, is lodged in a lake by rivers, must, therefore, remain exactly in the same irregular mass as when first imported and deposited ; and, accordingly, we never find the shores of lakes, or the banks of rivers, presenting the same distinct classification as is always found, more or less, on the sea shores. For the same reason we may be assured, that in draining marshes or lakes, when we cut through distinct strata of sand, marl, gravel, or fine clay, which are all generally found in strata in such situations, we are to attribute such deposits, as well as their fossil contents, to a period when the action of the sea was in force; and that the hollow basin-like form which now causes a marsh, or a lake, must have been at least partially coated with marine strata at the period of the Deluge. We must, however, be guided by circumstances, in forming a judgment in such cases, as there can be no doubt that many places, which were formerly shallow lakes, or marshes, are
These three laws, which have been in constant action since the first creation of the seas, the rivers, and the atmosphere, which events, history informs us, took place about 6000 years ago, are fully sufficient to account for a prodigious accumulation of decomposed mineral matter in the bed of the ocean.*
now nearly dry, from the growth of peat, or the accumulation of the debris of land streams; and we must, consequently, judge of the nature of the soils, and of the period of the fossil deposits, according to their degree of stratification, and the nature of the embedding soils.
The remains of deer and other animals often found in peat mosses, must, therefore, be considered antediluvian, or, otherwise, according to the situation in which they occur, and according to the presence or absence of land streams, by the agency of which the deposits might have been made. The well known fossil elks of Ireland, and of the Isle of Man, may probably be regarded as truly antediluvian; though geologists have often considered them as much more modern.
* In a late publication by Mr. Lyell, which has come under
notice since the above was written, and which is a work full of information of the most important kind, with regard to natural secondary causes, which he considers sufficient to account for all the appearances on the surface of the earth, we find a calculation with respect to the quantity of mud lodged in the sea by the Ganges, which appears, as it is well calculated to do, to shake to its foundation the theory of the author ; for it is obvious, that it proves too much to suit his idea of millions of years, as the age of the