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We know no more of the nature of the centrifugal power than we do of gravity, excepting that its agents are conspicuous in all its operations. These agents are heat and gas. We know that by the united, accumulated force of these two agents, even rocks are split asunder, and by an equable distribution matter can be forced upwards, as perspirable matter is from the pores. Water must be always forced up by the central point, either as seas or oceans in a direct manner through large rents or chasms, or else be pressed upwards to the surface and into space in imperceptible vapours. This latter assumption is predicated of a knowledge of the fact that moisture is always perceptible in the interior of the earth, being present in proportion to the capacity of the body to conduct it. Stones, metals, clays, sand, &c., are always more or less damp. Water is forced up through the interstices of sand to a great height; an instance of which is seen at this moment on the shore of the Gulf of Mexico. On the beach, directly in front of the town of Alvarado, there existed about a century ago a small ridge of sand, running about half a mile along the shore, and evidently thrown up by winds and waves. A fresh water spring was known at that time to exist at the northern extremity of this ridge, which was then but a few feet in height. The spring is there still, and supplies the inhabitants with fresh water, although the sand ridge is now a hill more than twenty feet high.

The water has therefore elevated itself through the interstices of sand, and we have no doubt that if this sand hill is increased to the height of a hundred feet or more, the water will find its way to the top. The interstices of sand in this case cannot be under the influence-the undue influence-of gravitating pressure, or the water would be unable to rise. Water, therefore, rises by a central impulse through fissures and chasms to the top of high mountains. This central power is as capable of elevating either solid or fluid matter to the greatest height, as of elevating the latter through a bored tube or a capillary tube.

We are tenacious of these opinions, because we do not wish to deter any one from boring for water in those places where, according to M. Garnier, there are no distinctive marks of subterraneous waters. We only concede, that in the immediate vicinity of mountains there may be a greater certainty of getting water at a slight depth, than at a great distance from them.

What a vast benefit one of these bored wells would be on a rice, cotton, or sugar plantation! Four or five thousand dollars is no object to a planter if he could have a full supply of pure water. More than the interest of this sum is expended every year in drawing up water from the deep wells now in use

throughout the West Indies. There many wells are from two to four hundred feet deep, and the cost of digging each is from one to two thousand dollars. The labour, the entire labour, of two or three slaves and four oxen is in daily requisition for drawing up water for the supply of the plantation. One or two bored wells, on a large estate, would enhance its value greatly.

A century must elapse before boring will be in general use. A few failures, owing to causes which have no relation whatever to the practicability of the scheme, will throw the art back until some fortunate circumstance shall turn up in its favour. The difficulties under which the art now labours are, first, want of faith in the party which disbelieves in a central power; second, want of science in the operator, who has not yet discovered an economical mode of boring; and third, the general apathy which prevails with regard to this important subject. We have, to be sure, very much simplified the process of boring; that is, our mode is far more simple and much less expensive than those described by M. Garnier. We use but few tools, either in limestone, alluvial, quicksand, or granite.

We have obtained water in rocks which were entirely of granite, even at so slight a depth as thirty or forty feet; and although these partial borings never produced an overflowing well, yet it served to prove that there were fissures and seams in granite rock. Borings have succeeded in red shell, or old red sandstone. One of these overflowing fountains was obtained in New Jersey, in this red shell, at the depth of two hundred feet, nor did the borers encounter a single stratum of clay or rock. This red shell continued throughout the whole boring; the only variation being softer or harder rock. This well is on the banks of the Raritan, eighty feet above the level of the river; it discharges its water through a tube, five feet above the surface, and has continued thus to flow since its commencement in 1825, a period now of twelve years. A more unpromising spot for boring, according to the theory of M. Garnier, could not well be selected, as there are no hills in the immediate neighbourhood, and the rock through which the boring passed is porous throughout the whole depth, and the common wells in the vicinity often fail in July.

Another well was bored about two miles higher up the Raritan, on the opposite shore. This is three hundred feet deep, but the boring passed through a great variety of rock, clay being found at the bottom, under which the water lay; for no sooner was the stratum of clay pierced, than the water rose to the surface in an instant.

A third well was bored in Somerville, about eleven miles distant from the one last mentioned, and although only three miles

from the Raritan hills, the boring was discontinued at the depth of five hundred feet, there being no overflow of water.

They are now boring in Paris, and have gone to the depth of twelve hundred feet! We presume the boring will continue till water is obtained; for in France they never suffer themselves to be discouraged when an important object is in question. We hope that they will go on with the experiment, even if they double the distance. In New York, where the people have suffered so many years for the want of pure and wholesome water, the Manhattan Company stopped boring at the depth of six hundred feet. They could not have much confidence in the theory or they would have proceeded further. An enterprising citizen, Mr. Holt, at his own expense, has bored to the depth of six hundred feet, and has obtained an overflowing fountain of very fine water. This boring is at the foot of Fulton street.

The great mistake is in the smallness of the hole; in general, the diameter is from two to three inches, and it can readily be imagined that in many cases these borings would have to be abandoned. If the chisel, or tool, break off at the bottom, there is no way of proceeding but by endeavouring to cut it up with new tools. If this is impracticable, the borers must begin again in another place, or abandon the project altogether. Thus far, the price of boring has been from two to two dollars and a half a foot, a price which prevents us from boring for an overflowing well. By referring to the American pamphlet, we perceive that there are a number of wells in New York that have been bored to the depth of thirty and sixty feet, at which depth veins of water were struck which enabled the borers to draw up the water by means of a small metallic pump. But the Manhattan Company should persevere in this plan of boring, and go to the depth of twelve hundred or two thousand feet. They should, however, abandon the old hole, and commence one of at least two feet diameter. Tools and machinery could be constructed of sufficient weight to cut through the granite with ease, and in this case, if a tool was either broken off or lost, it could easily be recovered. We have now before us drawings of a very simple set of machinery, which will answer the purpose exactly, for there is nothing required of the borer but ordinary judgment and some slight manipulating ingenuity. But apart from the exclusive theory, M. Garnier's memoir is worthy of being a manual in our military academies. Our engineers would then be regularly inducted in the theory and practice of this noble art, and the occupation of boring for water would be as respectable and lucrative as that of surveying coasts, roads, or canals. This art can never be of general utility until men of science engage in it as a profession. Its progress then will be similar to that of agriculture and horticul

ture; fifty years ago these arts were at the lowest ebb, and now men of the first abilities and character are engaged in them.

We close these remarks by strongly recommending M. Garnier's memoir to the attention of the American public, and advise a translation of it entire, for the use of those engaged in the art of boring. We have been compelled to very brief extracts, and have omitted much of what is curious and decidedly useful to certain sections of our own country. We likewise add the hope, that whilst due deference is paid to the talents of this distinguished gentleman, the art of boring may not be allowed to languish in America, even if we do not always meet with the indications that he describes. Trusting to the representations of the American author on boring, there are many cases wherein water can be obtained from other impermeable beds than clay, and assurance is given us that rocks of granite are often intersected by seams and fissures; a fact which the well bored by Mr. Holt fully establishes.

Even on the Halleyan theory, Artesien wells can be successfully undertaken in New York, for the Highlands and Snake Hill are near enough to hope for success on this principle. The appearance of these and other hills in the vicinity, proves that the crust of granite on which the city is built, is not very thick, and that seams or fissures may often be found, as the blocks of granite, by not lying horizontally, prove that they have been broken up. "They dip," as we are informed by Professor Anderson, "in a direction nearly between southwest and northeast;" and "in some places, along the eastern shore of the island, the granite has nearly a vertical position, inclining to the east, with a slight dip towards the west."

This proves that these granite rocks have been moved from their original position, and encourages the hope, that in many instances the borer will encounter seams and fissures, through which water may pass and rise to the surface.

ART. V.-Memoirs of Aaron Burr, with Miscellaneous Selections from his Correspondence. By MATTHEW L. DAVIS. In two volumes. Vol. II. New York: 1837.

We pursue our notice of the life and character of this very extraordinary man. In doing so, we regret that he has not found a more able biographer than Mr. Davis. Though there is an evident improvement in the style and manner of this late volume, as compared with its predecessor, it is, notwithstanding, clumsily and ungracefully put together, with neither strength of argument nor comprehensiveness of views on the part of the author. He has made, indeed, but an inefficient use of the valuable and interesting materials in hand, and has failed to exhibit the most plausible apology of which some of the actions of Mr. Burr admitted. He has done worse, however, than this. He has left much of the private conduct and operations of his hero in mystery-when he had in his possession, unquestionably, the means of placing them fully before the eyes of the public. No one can rise from the perusal of Burr's life-particularly that part of it which is subsequent to his leaving the vice-presidential chair-without feeling that there is much, very much in his career that is unknown to the reader; much that has rested in vague report-of a kind, too, to mar his fame as a man-about which the pages of Mr. Davis's book offer no explanation; and of which they say as little as the subject of the memoir himself is reported in his lifetime to have said, save to a very few of the confidential friends of his later years, of whom we take Mr. Davis to have been one. The author intended, and very properly, to pen no set eulogy-he professes but "to bury Cæsar, not to praise him"-yet the impartiality of history -the truth of biography required, that while no hollow praise should be accorded to his subject; on the other hand, no pervading traits of character-no active employments of years-no absorbing tastes, nor cares, nor pursuits, should be omittedand the reader left to form his estimate of the greatness or meanness of the individual from a partial exhibition of the events of his life. But we leave the biographer, in order to resume our notice of the prominent events in the course of Colonel Burr, and the developments of his character.

The career of Burr as a lawyer was, during portions of his life, and in a certain sense, a successful one. He acquired a large practice, much money, and an eminent reputation; and yet, from his biographer's own account, in the opinion of every honest man he but little deserved his fame. The lofty spirit and high-mindedness of the gentleman, which know no trickery and scorn a dishonest advantage, were not his. His were not

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