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and will afford abundant supplies of water for agricultural and domestic purposes and sometimes even for moving machinery. The quantity of water thus obtained in Artois is often sufficient to turn the wheels of Corn-mills.

In the Tertiary basin of Perpignan and the chalk of Tours, there are almost subterranean rivers having enormous upward pressure. The Water of an Artesian well in Roussillon rises from 30 to 50 feet above the surface. At Perpignan and Tours, M. Arago states that the water rushes up with so much force, that a Cannon-ball placed in the Pipe of an Artesian well is violently ejected by the ascending stream.

In some places application has been made to economical purposes, of the higher temperature of the water rising from great depths. In Wurtemberg Von Bruckmann has applied the warm water of Artesian wells to heat a paper manufactory at Heilbronn, and to prevent the freezing of common water around his mill wheels. The same practice is also adopted in Alsace, and at Constadt near Stuttgard. It has even been proposed to apply the heat of ascending springs to the warming of green houses. Artesian wells

These theoretical Results can never occur to the extent here represented, in consequence of the intersections of the strata by valleys of Denudation, the irregular interposition of Faults, and the varying condition of the matter composing Dikes.

If a valley were excavated in the stratum M below A", the water of this stratum would overflow into the bottom of this valley, and would never rise on the side of the fault so high as the level H.

Wherever the contact of the Dike H, L, with the strata M, N, O, P, Q, R, that are intersected by it, is imperfect, an issue is formed, through which the water from these inclined strata will be discharged at the surface by a natural Artesian well; hence a series of Artesian springs will mark the line of contact of the Dike with the fractured edges of the strata from which the water rises, and the level of the water within these strata will be always approximating to that of the springs at H; but as the permeability of Dikes varies in different parts of their course, their effect in sustaining water within the strata adjacent to them, must be irregular, and the water line within these strata will vary according to circumstances, between the highest possible levels, A, B, C, D, E, and the lowest possible level H.

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have long been used in Italy, in the duchy of Modena; they have also been successfully applied in Holland, China,* and N. America. By means of similar wells, it is probable that water may be raised to the surface of many parts of the sandy deserts of Africa and Asia, and it has been in contemplation to construct a series of these wells along the main road which crosses the Isthmus of Suez.

I have felt it important thus to enter into the history of Artesian Wells, because their more frequent adoption will add to the facilities of supplying fresh Water in many regions of the Earth, particularly in low and level districts, where this prime necessary of Life is inaccessible by any other means; and because the theory of their mode of operation explains one of the most important and most common contrivances in the subterraneous economy of the Globe, for the production of natural springs.

By these compound results of the original disposition of the strata and their subsequent disturbances, the entire Crust of the Earth has become one grand and connected Apparatus of Hydraulic Machinery, co-operating incessantly with the Sea and with the Atmosphere, to dispense unfailing supplies of fresh Water over the habitable surface of the Land.*

* An economical and easy method of sinking Artesian Wells and boring for coal, &c, has recently been practised near Saarbruck, by M. Sellow. Instead of the tardy and costly process of boring with a number of Iron Rods screwed to each other, one heavy Bar of cast Iron about six feet long and four inches in diameter, armed at its lower end with a cutting Chisel, and surrounded by a hollow chamber, to receive through valves, and bring up the detritus of the perforated stratum, is suspended from the end of a strong rope, which passes over a wheel or pulley fixed above the spot in which the hole is made. As this rope is raised up and down over the wheel, its tortion gives to the Bar of Iron a circular motion, sufficient to vary the place of the cutting Chisel at each descent.

When the chamber is full, the whole apparatus is raised quickly to the surface to be unloaded, and is again let down by the action of the same wheel. This process has been long practised in China, from whence the report of its use has been brought to Europe. The Chinese are said to have bored in this manner to the depth of 1000 feet. M. Sellow has with this instrument lately made perforations 18 inches in diameter, and several hundred feet deep, for the purpose of ventilating coal mines at Saarbriick. The general substitution of this method for the costly process of boring with rods of iron, may be of much public importance, especially where water can only be obtained from groat depths.

Among the incidental advantages arising to Man from the introduction of Faults and Dislocations of the strata, into the system of curious arrangements that pervade the subterranean economy of the Globe, we may farther include the circumstance that these fractures are the most frequent channels of issue to mineral and thermal waters, whose medicinal virtues alleviate many of the diseases of the Human Frame.f

"Thus in the whole machinery of springs and Rivers, and the apparatus that is kept in action for their duration, through the instrumentality of a system of curiously constructed hills and valleys, receiving their supply occasionally from the rains of heaven, and treasuring it up in their everlasting storehouses to be dispensed perpetually by thousands of never-failing fountains, we see a provision not less striking, than it is important. So also in the adjustment of the relative quantities of Sea and Land, in such due proportions as to supply the earth by constant evaporation, without diminishing the waters of the ocean; and in the appointment of the Atmosphere to be the vehicle of this wonderful and unceasing circulation; in thus separating these waters from their native salt, (which though of the highest utility to preserve the purity of the sea, renders them unfit for the

• The causes of intermitting Springs, and ebbing, and flowing wells, and many minor irregularities in the Hydraulic Action of natural vents of water, depend on local Accidents, such as the interposition of Siphons, Cavities, &c, which are scarcely of sufficient importance to be noticed* in the general view we are here taking of the Causes of the Origin of Springs.

-j- Dr. Daubeny has shown that a large proportion of the thermal springs with which we are acquainted, arise through fractures situated on the great lines of dislocation of the strata. See Daubeny on Thermal Springs, Edin. Phil. Mr. April, 1832, p. 49.

Professor Hoffman has given- examples of these fractures in the axis of valleys of elevation, through which chalybeate waters rise at Pyrmont, and. in other valleys of Westphalia. See PI. 67, fig. 2.

support of terrestrial animals or vegetables,) and transmitting them in genial showers to scatter fertility over the earth, and maintain the never-failing reservoirs of those springs and rivers by which they are again returned to mix with their parent ocean; in all these circumstances we find such evidence of nicely balanced adaptation of means to ends, of wise foresight, and benevolent intention, and infinite power, that he must be blind indeed, who refuses to recognise in them proofs of the most exalted attributes of the Creator."*

CHAPTER XXIII.

Proofs of Design in the Structure and Composition of * unorganized Mineral Bodies.

Much of the physical history of the compound forms of unorganized mineral bodies, has been anticipated in the considerations given in our early chapters to the unstratified and crystalline rocks. It remains only to say a few words respecting the simple minerals that form the ingredients of these rocks, and the elementary bodies of which they are composed.f

"In crossing a heath," (says Paley,) "suppose I pitched my foot against a stone, and were asked how the stone came to be there; I might possibly answer, that, for any thing! knew to the contrary, it had lain there for ever: nor would it perhaps be very easy to show the absurdity of this answer."*

* Iluckland, Inaug. Lecture, p. 13.

f The term simple mineral is applied not only to unoombined mineral substances, which are rare in Nature, such as- pure native gold or silver, but also to all kinds of compound mineral bodies that present a regular crystalline structure, accompanied by definite proportions of their chemical ingredients. The difference between a simple mineral and a simple substance may be illustrated by the case of calcareous spar, or crystallized carbonate of lime. The ultimate elements, viz. Calcium, Oxygen, and Carbon, are simple substances; the crystalline compound resulting from the union of these elements, in certain definite proportions, forms a simple mineral, called Carbonate of lime. The total number of simple minerals hitherto ascertained according to Berzelius is nearly six hundred, that of simple substances, 01 elementary principles, is fifty-four.

Nay, says the Geologist, for if the stone were a pebble, the adventures of this pebble may have been many and various, and fraught with records of physical events, that produced important changes upon the surface of onr planet; and itsrolled condition implies that it has undergone considerable locomotion by the action of water.

Or, should the stone be Sand-stone, or part of any Conglomerate, or fragmentary stratum, made up of the rounded detritus of other rocks, the ingredients of such a stone would bear similar evidence of movements by the force of water, which reduced them to the state of sand, or pebbles, and transported them to their present place, before the existence of the stratum of which they form a part; consequently no such stratum can have lain in its present place for ever.

Again, should the supposed stone contain within it the petrified remains of any fossil Animal or fossil Plant, these would not only show that animal and vegetable life had preceded the formation of the rock in which they are embedded; but their organic structure might afford examples of contri' vance and design, as unequivocally attesting the exercise of Intelligence and Power, as the mechanism of a Watch or Steam engine, or any other instrument produced by human art, bears evidence of intention and skill in the workman who invented and constructed them.

Lastly, should it even be Granite, or any crystalline Primary Rock, containing neither organic remains, nor fragments of other rocks more ancient than itself, it can still be shown that there was a time when even stones of this class

* I have quoted this passage, not in disparagement of the general argu. ment of Paley, which is altogether independent of the incidental and needless comparison with which he has prefaced it, but to show the importance of the addition, that has been made by the discoveries of Geology and Mineralogy, to the evidence of the non.eternity of the earth, which so great a master pronounced to be imperfect, for lack of such information as these modem sciences have recently supplied.

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