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flowing Thames, and observe the continual operations carried on by its unwearied waters. We shall find them charged with a load of earthy matter, collected, in their course, from the various formations through which the river flows. This burden must necessarily be of the most indiscriminate character; but these various bodies are to be deposited in an element where each species of importation is most exactly sifted, and every thing is arranged according to its own particular class. The muddy, the sandy, or the gravelly bodies, which are thus in constant motion downwards, from the highest sources of the river, are all at length submitted to the action of those laws of NATURE, which regulate the deep. We cannot suppose that all this earthy matter remains in the form of banks and shoals, near the immediate mouth of the river itself; for if this were the case, that mouth must long since have been completely blocked up. But, although we always find rivers closed, more or less, with a bar, occasioned by the contending action of the tide, and the stream; yet we do not perceive that bar materially to increase; for the exact balance is, at all times, kept up by the constant removal of superfluous matter, by the acțion of the currents of the neighbouring ocean.
* As an instance of the power with which rivers act, in filling up inland lakes, and in adding to the accumulations
If this, then, is the system now in action, on a small portion of our own shores, to what an extent must it be going on, around our whole island. And if we extend our view, and conin the bed of the sea, the following example may serve to give an idea.
The river Kander, a mountain torrent of no great size, rushes down the valley of Kanderthal, in the Canton Berne, in Switzerland, and enters the lake of Thoun, about four miles from the town so called. About a hundred years ago, this stream did not flow into the lake, from which its course was cut off by a ridge of diluvial hills of several hundred feet in height, stretching along the south side of the lake, in a north-westerly direction. This diluvial ridge, extending more than ten miles in length, is entirely composed of rounded gravel, or pudding stone.
In consequence of the mischief done by the overflowing of the Kander, to a great extent of valuable meadow land, in its course to join the Arr, ten miles below Thoun, which was its natural course, a spirited plan was proposed and adopted, for cutting a subterraneous passage for the river, through the above mentioned ridge, at a place where it approached the lake within about a mile, and thus admitting it into its bed. This passage was cut in the beginning of the last century, (about 1715.) The descent was rapid, from the lake being considerably lower than the old course of the river. At this period, the depth of the lake was in proportion to the steep hills forming its shore. The Kander had not long followed its new subterraneous course, when it greatly enlarged the artificial tunnel, and hurried great quantities of gravel into the lake. The rapidity of the torrent in a few years enlarged its course, till at length the whole superstructure gave way, and fell in ; so that there sider the more gigantic scale of the rivers on the continents, and the more direct influence of the great currents upon their vast importations, we shall find a cause fully sufficient for the formais now a most romantic wild glen, where, a century ago, there was smooth pasture and wood lands. The effects of the torrent soon became apparent in the lake : an immense quantity of gravel, and every species of rock, was carried in by the current, and lodged in its bed. In 1829, when I lived in that neighbourhood, the bed formed of this debris, was of not less extent than 300 acres; the greater part was covered with thick wood; and this secondary formation is every year increasing in the same proportion; so that, as the lake is not there of great breadth, there is every prospect of a rapid and most material change taking place in its form. I have sounded the lake at the present mouth of the Kander, and, as I found no bottom with a line of about a hundred feet, we are certain that this mountain stream has, in little more than one century, produced a secondary bed of mixed materials, of fully three hundred acres, and at least one hundred feet in depth.
One circumstance, however, is worthy of remark, with respect to such secondary formations in fresh water lakes ; and that is, that in consequeuce of the absence of tides and currents, and that constant lateral movement kept up in the bed of the sea, we never discover in them that stratified regularity so remarkable within the action of the tide. The inixture of mineral bodies carried into an inland lake, remains, therefore, exactly as deposited at the first, and this must always be in great confusion. This difference of effect, may, perhaps, be safely taken as a guide, in judging of what some geologists have called salt and fresh water formations ; and if this idea be correct, we have an additional
tion of secondary deposits of great depth and variety, in the course of a comparatively short space of time.
evidence against the extraordinary theories of Cuvier, who supposed the well defined strata of the Paris basin to have been occasioned by the alternate occupation of that basin, by salt and fresh water. The rounded pebbles and sand, found in lakes, are never formed in the lakes themselves, as they are in the bosom of the sea; but are carried into them by the rivers nearly in the shape in which we find them.
It may, therefore, be safely assumed, that the regular strata of sand, of gravel, or of fine clay, found in mosses, and shallow lakes, if quite distinct from other strata, must have been formed at the period of the Deluge, under the influence, and by the agency of the action of the sea.
The Deluge.- Traditional Evidence of that Event.-Er
roneous Ideas commonly entertained respectiny it.—Distinctness of Scripture on the Subject. – Evidence from Scripture. -Evidence from the Ancient, though Apocryphal, Book of Enoch.-Theories of Philosophy on the Subject.The most probable Cause of that destructive Event.
In the former part of this work, and in taking a general view of the phenomena presented to our observation on the surface of our earth, a confident hope was held out, that we should be able fully to account for all those phenomena, by considering, with a candid and unprejudiced judgment, the three great events recorded in history, viz. Ist, the creation of the world; 2d, the formation of a bed for the gathering together of the waters, together with the action of the laws of nature within that bed, for upwards of sixteen centuries; and, lastly, the Deluge, as described by Moses in the Book of Genesis. We have already, at some length, considered the two first of these great events; and in the last of the two, we have found an unquestionable source of very extensive secondary formation, and sufficient to account for a large proportion of all those, actually existing, on the primitive surface of the earth. We have thus