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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[March, 



From this explanation, however, we entirely dissent , and fear not to affirm 

 that under such circumstances water never cuuld rise on the principle of a 

 syphon. In order that a jet of water, whatever may be its dimensions, shall 

 work with certainty, one condition is indispensably necessary, viz., the un- 

 interrupted continuity of the curved tube charged with conducting it from 

 the reservoir above to the less elevated region where the jet is required to 

 play. All the force of ascension in the second branch of this tube ought to 

 be derived from the accelerated velocity of the water in the fust branch, and 

 this acceleration would be as inevitably broken and annihilated by any ob- 

 stacle, as by the entire destruction of the continuity. Now, in the interior 

 of the earth, to whatever depth we may penetrate, we can find nothing re- 

 sembling continuous tubes ; everything there is more or less friable, casual, 

 and irregular. Thus, whatever pains the engineer may take in order to reach 

 by the smaller end of his vertical tube the surface of a subterranean sheet of 

 water, it will all be useless unless by a very astonishing fortuitous accident, 

 he should meet with another tube of the same calibre, ascending without rup- 

 ture to the upper reservoir. If, as some believe, it be in the mountains of 

 Burgundy that this reservoir is placed, is it possible to conceive the existence 

 of a continued oblique tube ascending from beneath Paris to the neighbour- 

 hood of these mountains? Besides, no one appears to doubt that M.Mulot"s 

 choice of a situation for his well was perfectly arbitrary, and therefore if he 

 had attempted to construct one upon the Place des Invalides or in any other 

 part of the capital, he would have equally succeeded. Hence, then, it will be 

 granted that in and around Paris it would be possible to dig an indefinite 

 number of Artesian wells, all which would be fed by the mountains of Bur- 

 gundy ; and in order to explain this, we must picture to ourselves the upper- 

 most beds or strata of earth under Paris and the surrounding country within 

 a circle of two hundred leagues diameter, invariably woven into an inex- 

 tricable net-work of which each filament is an unbroken tube. Assuredly 

 nothing like this exists. 



There are others who have sought to explain the rise of water by 

 conceiving two concave vases, or two immense cisterns of unequal diameter, 

 placed one within the other, the basin of Paris occupying the centre. They 

 imagine that the margins of these vases extend from the mountains of the 

 Vosges on the east, to Havre on the west ; and from the plains of Flanders 

 on the north, to the mountains of Burgundy on the south. They suppose 

 that between these two vases there is a space filled with sand. The rain 

 Water which penetrates into the pores and cavities of the sandy district is 

 retained there by the dense matter of the two vases. The water maintains 

 the same level through the whole of the sandy space, but it does not pene- 

 trate into the basin of the higher or smaller vase. Hence it follows, that by 

 boring vertically through the basin, the water confined in the sand will in- 

 stantly rise to the height of that which exists in the circular reservoir all 

 iound it- This is certainly a very amusing geological disposition of things, 

 but unfortunately it is supported neither by facts nor reason. A continued vase 

 with a double bottom, more than a hundred leagues in diameter, fixed in the 

 bosom of the earth ! A vase whose inferior limits, as shown at this day by 

 the well of Grenelle, are no less than 1690 feet deep, and into which 

 flow all the subterranean waters from all the surrounding shores! What 

 a gigantic disposition of things, and no less gigantic than admirable! 

 A god must he have been who founded Paris, and cradled the capital of the 

 world in the centre'of this'marvellous vase ! Kidiculous idea to imagine, even 

 if this vase exist, that it should be unbroken throughout so vast an extent. 

 Do we not know on the contrary that the vase is cut up and divided into 

 many irregular compartments? Throughout the prodigious extent of space 

 which is claimed for the field of this theory, as at Tours, at Elbceuf, at St. 

 Denis, and St. Ouen, numerous Artesian wells have already been constructed, 

 and all these wells of many various depths are much shallower than that of 

 Grenelle. Has each well, then, its respective vase encased in the general 

 vase, and resting upon its own particular bed of sand ? If such be the fact, 

 we must suppose that a great number of Artesian stages exist in the general 

 Vase. But in this case, why did not the water rise at Grenelle when the augur 

 had reached one of these elevated stages, that of the St. Ouen for example, 

 so near to Grenelle? Does not the Artesian vase of St. Ouen extend to the 

 abattoirs of Grenelle ? If not it must be singularly circumscribed. It has 

 nevertheless supplied for fifteen years two constant fountains, and the Arte- 

 sian wells of Tours, Elbceuf, and St. Denis are equally inexhaustible. Doubt- 



less we may construct an indefinite number of Artesian wells upon the surface 

 of the country which surrounds Paris ; indeed this experiment has been made 

 in various places, and according to a report addressed to the Academy of 

 Sciences, dated 15th March, 1841, we find that "many of these wells bored 

 at the bottom of a valley, yield no water, whilst others fixed upon the side of 

 a hill, furnish an abundant flow." What inexplicable mystery in the hypo- 

 thesis of a sheet of subterran an water fed by rain, and springing up only 

 from inferior cavities to establish a horizontal equilibrium. Again, if it be 

 said, that the general vase, the centre of which is placed beneath Paris, 

 receives throughout the whole circle of its sandy borders the rain water from 

 the Vosges, from Burgundy, from Bretagne, and from La Vendee, we ask how 

 it is that all these waters, flowing over slopes of many different inclinations, 

 but all of them more or less steep, and always repairing to the same cavities, 

 has not long since choked up its own passage by the sands which it must have 

 carried along with it. The great sands in the Delta of the Nile, in the Gulf 

 of Gascony, and in the Aigues Mortes, all teach us the inevitable results of 

 continual deposits. And if we suppose that the two cisterns here spoken of, 

 are formed of a substance impermeable to water, such as glass, or porcelain, or 

 baked earth, how has it happened, that buried in the earth during many ages, 

 they have never experienced any shock or accident which would have broken 

 them to pieces? Itis evident if any thing of this latter kind had ever occurred, 

 that the water which had lodged in the interval between the two vases, would 

 naturally pass through the fissures and ruptures into the cavity of the upper 

 vase, thus destroying the internal arrangement of the hydrostatic machine, 

 whose existence has been so gratuitously assumed. Besides, if this machine 

 really exists under the basin of which Paris occupies the centre, if it has its 

 circumference at Havre, at La Fleche, in Burgundy, and at the foot of the 

 Vosges Mountains, we could not construct Artesian wells at any of these 

 points, for throughout the whole of this circumference, the aqueous reservoir 

 would be only at its origin and would have no vase to rise into. And yet, 

 nobody doubts that in the neighbourhood of all these boundary districts, the 

 Artesian well has as much chance of success as at Paris, St. Denis or Elbceuf. 

 It is also known that the Artesian wells of Tours have succeeded, although 

 on the south side of the basin of Paris. 



By the simplest laws of physics, we shall now show how imaginary is 

 this Artesian source of water. M r e are told that through immense beds of 

 sand the water sinks from the surface of the soil into the grand subterranean 

 cavity. But who does not know that, when obliged to sift itself through a 

 bed of sand, however loosely disposed, water loses all motion, except a kind 

 of slow and difficult leakage. Towards the base of our artificial sandy 

 fountains it comes only drop by drop, and it loses in its course all the velo- 

 city due to the space it has passed through, and all the pressure due to its 

 weight. If the spout which discharges the water should open upon a bent 

 tube with an ascending branch, the water would not rise above the level of 

 the space which it already occupied in the base of the fountain. This 

 would be its whole hydrostatic power ; and if the ascending tube were full 

 of sand, it would rise something above this same level : but, in that case, 

 the effect would be due entirely to capillary action. The most striking ob- 

 jection, however, still remains. During the summer, what becomes of the 

 rain water immediately after falling. The greater part, instead of sinking 

 into these profound depths, is evaporated and carried off through the at- 

 mosphere, and it is very seldom that either our fields or gardens, the morning 

 succeeding a storm, show any traces of moisture more thau a foot in depth. 

 Would not the alternation of wet and dry weather cause an incessant varia- 

 tion in the flow of an Artesian well, seeing that this incessantly varies the 

 supplies of our fountains and the height of our rivers ? Ob, no! in spile 

 of all this, the Artesian wells have always the same volume, and in truth, 

 acknowledge neither summer nor winter. We shall, hereafter, explain the 

 constancy of Artesian wells. But, in the first place, we must consider 

 another gratuitous supposition. Let us first explode all error, we shall then 

 more easily arrive at the truth. It is said, by some, that the rain water and 

 that which proceeds from the melting of snow, sink into a subterranean hori- 

 zontal region void of solid matter, but hemmed in above and below by two 

 beds of impermeable clay. Upon the upper one reposes an enormous mass 

 of chalk and other calcareous stone, which bears with all its weight upon 

 the volume of water underneath, and this weight forces the water to rise 

 vertically at every place where an opening is made down to it from the sur- 



