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with drawings and descriptions of such wells as were already bored, and with profiles (coupes) of the districts through which these wells passed.

2d. To state the reasons which ought to determine their introduction in places where these wells are unknown.

3d. To describe the local circumstances and reasons which ought to prevent experiments from being made in places where it would be desirable to have these wells.

4th. To estimate the expense of boring in different kinds of earth.

5th. To describe the accidents and inconvenience to which these bored wells were subject, with the manner of preventing or remedying them.

Added to this, the society expected that the memoir would embrace an accurate description of the different tools and instruments which were used by the borers. M. Garnier's memoir comprehended all this; and so satisfactorily, so amply, did it meet the wishes of the committee appointed to examine its pretensions, that the two inferior prizes were allowed to merge in the first. We fully agree with the committee, that M. Garnier has made one of the most circumstantial expositions that has ever yet been presented to the public on any subject connected with the arts. Whether all the minutiæ that he has laid down in his work be essential to the boring of these Artesien wells, is left for the consideration of the French, with whom these overflowing wells originated. With respect to America the case is different; we adopt a more simple process.

In many instances, as is stated in the American pamphlet on boring, if it be not expedient to go to the expense of an overflowing well, a cast-iron tube is inserted at once at the surface, which tube is generally from eight to ten inches in diameter. Through this tube the boring commences, and through it, likewise, all the pulverized rock and soil is abstracted by means of proper tools. When the tube is cleared out, it is driven down deeper, and another tube of the same diameter is fastened on the top, with collar and rivets. This in turn takes the place of the first, and so on, until the borer comes to the solid rock, where he invariably obtains water. This process is adopted in New York—and when the water has risen in these iron pipes to a sufficient height, a small metallic pump is introduced, which gives an abundant supply of water. This water, in all cases that have come under our observation, is much better than that which is supplied by the Manhattan Company.

All the minute details, therefore, of the shape of the boxes, (coffres,) with the care and precision required to insert them properly, are quite unnecessary as preliminary steps; and so likewise with the immense variety of tools recommended by M. Garnier.

It is singular that there should have been a simultaneous movement in France and England with regard to boring these wells. The author of the American pamphlet observes, that this art, though long known in Europe, was practised also in America for many years, but that in our country it was only resorted to for the purpose of obtaining salt water.

It was in May, 1824, that the first bored well for fresh water was begun in the United States. The first intimation that we had of such an event in England, was in September of the same year. M. Garnier's work was published in 1822, but gladly as we should have availed ourselves of its important statements, we began the process without its aid, as the work was entirely unknown to us. Whether the process is still carried on in England we know not, but at present a splendid trial is in progress in Paris, and by the last accounts they had bored to the depth of twelve hundred feet!

General La Fayette took a set of our boring tools with him from this country, for the purpose of getting an overflowing stream at La Grange. But as he did not make the experiment, we must infer that he was deterred by the result of M. Garnier's philosophy, which teaches, that unless there are certain indications-all of which he has very minutely specified-there can be no prospect of obtaining water. La Grange might not have presented any of those indicia which M. Garnier thinks indispensable.

The report of the committee occupied twenty-four pages; and there were the strongest and the most flattering recommendations of the work throughout. In conclusion, they advised that proper measures should be pursued for bringing the work before the public, as the subject was of the greatest importance to agriculture.

As the memoir was accompanied with nineteen plates, and to print the whole creditably a greater expense would be incurred than the funds of the society warranted, the minister of the interior was applied to in their behalf. With great liberality and promptness the request of the society was granted. The memoir was printed at the expense of the general government. Three thousand copies were struck off ; each member of the society received a copy; a suitable number was given to the author; and the residue distributed at the discretion of the society.

It is in this way that talent and genius are fostered in France. A society offers a liberal reward for the best essay on some useful art; this arrests the attention of scientific men, some of whom require the stimulus of pecuniary reward. Six hundred dollars is not a large sum, to be sure, but still it is desirable, and is some remuneration for loss of time. When fame and useful

ness are thrown into the balance, even this small sum is of sufficient weight to bring talent to the task.

No sooner is it decided that an author's labours are practical and useful, than his fame becomes a national concern. From the simple elevation he has attained in a chartered society, he is raised to the notice of the government, and held in reserve for some important occasion when his peculiar talent can be still further put to the test. He is not only, therefore, distinguished among a particular class, but by the liberality of the French system he is placed so conspicuously as to be introduced to all. The talent, also, of an individual thus becomes a national concern, and it matters not whether he belong to l'Ecole de Royale Mine, or l'ecole de cordonnier- whether he come from the north or the south ; for he is not estimated, as in many other countries, by geographical position.

To this liberal spirit in the French government do we owe the publication of M. Garnier's able work, the subject matter of which is fully as important to us as it was to his own countrymen. Although it is nearly fourteen years since it first made its appearance, yet, as it is still new to us, we feel it an imperious duty to call the attention of the American people—particularly those of New York—to its contents.

"1st. Researches relative to borings undertaken in the Province of Artois—and the depths to which they had attained.

“ The first attempt at obtaining these central springs, appears to have been made in a portion of country which comprehends the department of the Pas-de-Calais, composed of the ancient provinces of Artois, Bolonais, Calaisis, Andresis, and a small part of Picardy. At least this is the general opinion; and what appears to confirm it is the name of Artesien wells, given to similar wells which had been established in other places. This discovery in Artois seems to have arisen from the slight difficulties that were encountered when digging wells in Bethune, the waters in these rising nearly to the surface. After a time, as this mode of getting water was expensive, they by degrees invented other instruments and other methods by which they could penetrate the earth to a great depth. So that at present water can be brought to the surface, when local circumstances permit, from the depth of three hundred feet; and the water thus obtained is so pure and limpid, that in certain places it is used for all the ordinary purposes of life.

"2d. Nature of the earth in which these waters are contained.

"In attentively examining the different sections that we have gone through, we perceive that the waters obtained by boring are all contained in fissures of chalk rocks, which lie under strata of different degrees of thickness—as vegetable earth, sand, pebbles, and clay. All the wells dug in Ardres, Choques,

Annezin, Aire, Mervil, and Blenzel, show the same strata of earth and rock. We learn, likewise, that the farther we remove from certain districts, and the thicker the strata become, the deeper the calcareous chalk will of course be found under the abovementioned strata. We may conclude, therefore, that by following the course of peculiar strata, we shall be able to obtain these subterraneous waters without much labour."

“9th. We have endeavoured to describe, with geological precision, the geological peculiarities of the department of the Pas-de-Calais, not because the place seemed the most interesting for our examination, but to show that the conclusions drawn from this place are of a general nature. We observe that the Artesien wells constructed in Boston, in the United States of America, like those of the Pas-de-Calais, are fed by waters, in their turn fed from waters proceeding from limestone rocks; and that those situated in Sheerness in England, at the confluence of the Medway and Thames, prove, likewise, that at the depth of three hunded and fifty feet, at the bottom of a stratum of clay, there existed a bed of limestone in which the water was pure and limpid. So soon as the bed of clay under which the water was confined was pierced, the water rose suddenly to the height of three hundred and forty-four feet, but it fell as suddenly, and continued stationary at the depth of one hundred and twenty feet below the surface. « This sudden rise proceeds, without doubt, from the oscillation which it undergoes as soon as it is relieved from the pressure that exists against the bed of clay which covers the chalky limestone. We must consider the wells that are opened in this way as one of the branches of a syphon, and the subterranean fissure as the other branch."

"11th. It is therefore certain that these waters come from some distant mountain, and that by the continued series of fissures, which exist in limestone rocks, they make their appearance at such places as Cape Blanc-nez, because the termination of the fissure at the steep side of such hills allows the waters to escape with ease.

“12th. No other rock possesses the same advantages for bored wells, of course we should not commence boring in primitive rocks, such as granite, gneiss, porphyry, serpentine, foc. These rocks have but few seams, and the rents through which waters traverse only extend to a short depth. Experience teaches us that waters which are concealed in primitive rock only flow to a short distance from the place whence they first filtered. In calcareous earth the fissures extend to a great distance; they are large and deep, and can circulate with ease under valleys, the bottoms of which are always covered by clay, sand, pebbles," &c.

“15th. But supposing that the natural outlets through which



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waters flow are very small, it is possible that a single attempt at
boring may prove unsuccessful; this, however, should not dis-
courage us. We may have happened to commence at a place
where the calcareous rocks are very compact and homogeneous,
and without fissure to the whole depth of the bored aperture.
Several cases of this kind occur in the fauxbourg of Bethune.
A person obtained an overflowing stream after boring to the
depth of only sixty or seventy feet in new earth, and thirty feet
in limestone. A neighbour of his bored to the same depth in
new earth, composed of sand and gray clay, which contained a
great quantity of pyrites. He then encountered the limestone,
through which he bored to the depth of one hundred and five
feet without getting water.

"16th. The cases just cited prove that his not getting water
at the depth of one hundred and seventy-five feet, when it was
obtained at a much less depth a few paces off, arose from the
circumstance of the bored hole having passed through a very
compact limestone that was without fissures. And yet, perhaps,
had the boring continued a few feet deeper a clay stratum might
have intervened under which water would be found, and thus
rise to the surface. It must be remarked, however, that clays,
found at such depths, proceed from a greater distance than
those from which we generally obtain water by boring, and of
which we have already spoken. These beds of clay, com-
mencing at some higher elevation, and continuing down under
many of the valleys, are so compact that they are impermeable.

The works undertaken at Blenzel prove that the whole mass of
limestone did not contain any water, and that it was only found
at the junction of clay and limestone. In this case it is evident
that these waters cannot have any communication with the
upper limestone beds, because the impermeable beds of clay
hinder the water from filtering or percolating through it to the
stratum of limestone under it.

“17th. In general, wherever we encounter chalky limestone,
very compact and homogeneous, it will be necessary to bore
deeper, until some variation in the rock appears, for we know
by experience that it is always at the junction of different rocks
that we obtain water. This junction facilitates the flowing and
spreading of waters on account of the vacuums and fissures
which the different strata exhibit. It is to the same cause that
we may attribute the increase of water when we arrive at the
junction of limestone and silex. Presuming, then, that we may
obtain water after boring to some depth through limestone rock,
it is nearly certain that the volume of water will be very much
increased, if, in continuing to bore, we encounter small beds of
pebbles (cailloux.)

“ 18th. Whenever a district does not present the geological

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