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tussocks as they appear before him, for here the soil is firmest. If his foot slip, or if he venture to desert this mark of security, it is possible he may never be heard of. In 1772 on the 16th of December, this moss being filled with water during heavy rains, burst, and a stream of black half-consolidated mud began to creep over the plain, it overwhelmed some cottages, and covered an area of 400 acres to a depth of fifteen feet. Dr. Jackson mentions that in the peat bogs of Maine, a substance exactly similar to cannel, or anthracite coal, is found amidst the remains of rotten logs of wood, and beaver sticks. It is a true bituminous coal, probably formed from the balsam-fir during its long immersion in the humid peat. We have now briefly considered the action of rivers, and running waters, their effect in carrying down to the ocean or lake a vast quantity of sediment, which is finally deposited, and subquently, either by pressure, or exposure to air consolidated into rock ; that large tracts of country called deltas, at the mouths of rivers, are in progress of formation, in which are buried the remaius of animals and vegetables, and in which, are preserved the tracks of worms, molusces, and birds; that by collections of rafts upon the large rivers, Iaden with stones, earths, and sands, islands are forming, and the materials for future beds of coal collecting ; that peat bogs are now growing, and, bursting their barliers, flooding whole tracts of country, and imbedding forests, and the habitations of men. By similar actions, exerted at the most remote periods, the present strata of the earth's crust were deposited, and the masses of limestones, sandstones, and shales, were formed. We are thus irresistably led to the conclusion, that however remote may have been the date of these formations, or however deep they may now be buried below the present surface, they were once exposed, and over their surface living things moved, and upon it lay the wrecks of organic matter. The entire absence of human remains or works of art in the anciently formed deposits, and their extreme abundance in modern alluvium, is a sufficient proof of the comparatively recent origin of the human race. It cannot be doubted that human rey

mains are as capable of resisting decay as the harder parts of many inferior animals. Such remains however, except in places subject to great change from volcanic action, or the shifting and filling up of the ancient channels of rivers, are never discovered. The inference is plain, and we are irresistibly led to the conclusion, that long antecedent to the date of man, the surface of the earth teemed with life; and that it has been subject to mighty revolutions, which have, at once swept off its face, whole races of its former inhabitants, whose fossilized remains have formed the bed of a mighty ocean. It was therefore a splendid boast, that the deeds of the English chivalry at Agincourt made Henry’s chronicle — as rich with praise

As is the ooze and bottom of the deep
With sunken wreck and sunless treasuries :

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“Thou dost wear
* No stain of thy dark birthplace; gushing up
From the red mould and slimy roots of earth,
Thou flashest through the sun.” -
Bryant.

In the present chapter we shall consider another aqueous cause of change, springs, or as they have been termed “subterranean drainage.” Every one is familiar with the fact, that the water which is deposited upon the loose soil, easily percolates through it, and makes its way 'downward to a certain depth according to the nature of the underlying strata. Whilst it easily penetrates through the gravelly, and sandy formations, it is arrested by the almost impervious beds of clay, and sometimes collected into large sheets of water, which are often subjected to intense pressure, upon the well known hydraulic principle so often employed in the arts under the form of the hydrostatic press. Mr. Lyell mentions that the transmission of water is so rapid through the loose gravelly soil over which the river Thames flows, and which is upon an impervious sub-stratum of clay, that the wells in this vicinity alternately ebb and flow, with the tides of the river. It is from this cause, that wherever on the side of a hill, strata of clay are found below sandy soils, the water oozes out, not indeed in a continuous sheet, but, probably from some slight difference in the constitution of the clay, or from natural fissures or cracks, in the form of little streams. The effect of such minute streams in finally undermining hilly tracts of country is surprising ; constantly running, they bear out the light sand, and thus the subterraneous reservoir extends its surface gradually, until, at length, the superincumbent mass gives way, and sliding upon the slippery clay is precipitated into the valley below.

Much light has been thrown upon the theory of springs by the boring of what are called “Artesian Wells,” so called from having been first made at Artois in France; they are made by boring the earth with a large augur, three or four inches in diameter. If a hard rock is met with, it is triturated with an iron rod, and the fragments are then easily removed ; as the boring proceeds, tubes are introduced to prevent the sides from caving, and also the spreading of the water through the soil. In this manner a well was bored for Holt's Hotel, in the city of New York; 136 feet of stratified sands, clay, and river mud, were first penetrated before reaching the gneiss rock which underlies the island, 500 feet of this rock was subsequently bored through, and an abundant supply of good water obtained. When a vein of water is struck, it often rushes up with great force, rising several feet above the surface, affording a constant supply of water. Borings have been made in France to a depth of 1200 and even 1500 feet. Occasional failure is experienced in boring, sometimes on account of the geological structure of the country, and often from the existence of subterranean outlets for the water. The following diagram is from Mr. Lyell, and will illustrate the principle of the

Artesian wells. Suppose a a, to be a porous stratum lying upon an impervious bed of clays and marls, d; and covered by another mass of impenetrable rock e. Suppose now that at some point as at b, an opening be made which gives a free passage upward to the water confined at a a, at so low a level as to be subjected to the pressure of a considerable column of water, which we may suppose collected at f, in a more elevated district. The water will rush out at b, and rise to a considerable height; and if there should happen to be a natural fissure at c, a spring would be produced. Among the curious facts made known by the borer, is the existence of distinct sheets of water, in strata of different

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springs, 209

ages and composition, and also of subterranean passages. At Tours, seeds and stems of marsh plants were brought up, and in such condition that they could not have been more than three or four months in water; and at Westphalia, small fish were thrown out, three or four inches long, the nearest streams being at the distance of some leagues. In boring an Artesian well near Buffalo, recently, for the purpose of obtaining pure water for the use of the Gas Works, after having penetrated some 25 feet from the surface, the laborers came upon limestone rock; upon penetrating this rock twenty-five inches, the drill fell into a cavity, and upon being withdrawn a jet of water followed, and continued to flow, until the water in the well rose to the level of the lake. Subsequent observations have shown Lake Erie to be the supply fountain, for when the waters of the lake rise or fall, by the action of wind, the water in the well changes its level in conformity. It appears that one of the large and numerous fissures common in this particular series of rocks, and which in this case communicated with the lake was pierced by the drill, and furnishes a fine illustration of the law which governs the production of springs and fountains. By the long continued action of underground streams, caverns and fissures, are formed and enlarged, and it is highly probable that rivers are flowing within the surface of the earth. In Staffordshire there is a spring which discharges annually more water than all that falls in the surrounding country. In Virginia, ten miles from Harrisburg, is a spring called the “Big Spring.” It rises suddenly from the foot of a himestone hill, and continues a stream some yards in breadth, and half a foot deep, with force sufficient to turn two large mills. At Kingston, Rhode Island, there is a spring which rises from primitive rocks, and discharges such a quantity of water that it grist-mill has been driven by it for a great number or years, and more recently a large cotton factory has been erected, which depends entirely upon the water of this spring to turn the whole machinery. In flowing through the different strata, springs become impregnated with various mineral substances. The solvent power of water exceeds that of any other liquid, and hence most spring waters are charged with

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