ARTESIAN WELLS ASPHALTE. 



233 



These reservoirs and these channels are created , 

 by fractures in great areas of stratified rock occa- 

 sioned by the action of a mighty power, which, at ' 

 some period, has broken them in various directions. 

 In some cases, these cavities actually withdraw from 

 the surface considerable rivers. The Guadiana 

 loses itself in a flat country, in the midst of a vast j 

 prairie: and when a Spaniard hears an Englishman 

 or a Frenchman speaking of the bridges of their 

 respective countries, he will tell them that there is 

 one in Estremadura on which 100,000 cattle can 

 graze. The Meuse and several other rivers in 

 France also disappear in the same manner ; some 

 being sucked in by apertures in their bed, situated 

 at various distances along the course of the stream. 

 In the Austrian dominions, the river Poick pursues 

 its course in the cavern of Adelsberg, where its 

 waters lose themselves and re-appear several times. 

 This cavern has been penetrated for the space of 

 two leagues from its entrance, at which point a lake 

 presents itself which has not yet been crossed. 

 Humboldt mentions a cavern in South America, 

 about twenty-five yards high, and twenty-seven or 

 twenty-eight broad, which the traveller can pene- 

 trate for 800 yards, into whose recesses are rolled 

 the waters of a stream above ten yards wide. The 

 grotto of Windborg, in Saxony, is also a remark- 

 able instance of the extent of the earth's internal 

 communications, being connected with the cavern 

 of Cresfield, from which it is some leagues distant. 



The Artesian fountain at Tours recently pre- 

 sented some phenomena proving the existence of an 

 extensive and complete line of subterranean com- 

 munication. In January, 1831, the vertical tube i 

 by which the waters of this fountain ascended was 

 shortened a little more than four yards, on which ) 

 its volume was immediately augmented a third;! 

 but this sudden increase rendered the water less 

 clear than usual. During many hours there were 

 brought to the surface, from a depth of above 110 

 yards, various substances, among which were re- 

 cognised twigs of hawthorn, several inches in 

 length, blackened by their long stay in the water, 

 stalks and roots of marshy plants, and seeds of \ 

 various kinds, in a state which showed that they 

 liad been in the water since the harvest, and, con- 

 sequently, that about four months had been spent 

 in performing their hidden voyage. Shells, and 

 other deposits which a small river, or stream of 

 fresh water, leaves when it overflows its banks, 

 were also brought up during the increased action of 

 the fountain, proving the freedom with which they 

 circulated at the depths below. 



An instance is mentioned by M. Arago in the 

 ' Annuaire" for 1835, of one of these subterranean : 

 rivers being reached by some workmen who were \ 

 boring for water close to the Barrie're de Fontaine- ' 

 bleau, at Paris. As usual, the progress of the 

 work was slow, but, all at once, the boring-rod 

 descended nearly eight yards. When they attempted \ 

 to withdraw it, it was evident that it was suspended ; 

 in a body of water whose current was so strong as 

 to occasion the instrument to oscillate in a particular 

 direction. 



Tn*e temperature of Artesian springs is invariably 

 higher in proportion as their depth increases. The 

 deepest of which we have seen any statement is 

 near Dieppe, and is about 340 yards below the sur- 

 face. A well formed near Perpignan produces 

 about 425 gallons per minute; and one at Tours 

 ascends more than two yards above the surface, and 

 gives 342 gaHons per minute. 



In France, the waters of Artesian springs are 

 sometimes made the moving power in corn-mills. 

 At Frontes, near Aire, the waters of ten Artesian 

 springs put in motion the wheels of a large mill, 

 and act besides upon the bellows and forge-hammer 

 of a nail-manufactory. At Tours, a well of nearly 

 150 yards in depth pours 225 gallons per minute 

 into the troughs of a wheel seven yards in diameter, 

 which is the moving power of an extensive silk- 

 manufactory. Besides their general utility in irri- 

 gations, and for purposes of domestic comfort and 

 salubrity, the water of Artesian springs has been 

 specially applied with advantage for other useful 

 objects. The workshops of M. Bruckmarm, in 

 Wiirtemburg, are warmed by means of water con- 

 veyed in pipes from an Artesian spring, the tem- 

 perature of whose source is considerably higher 

 than that of the atmosphere. M. Arago also states 

 that there are green-houses whose temperature is 

 kept up by means of the circulation of a constant 

 volume of Artesian waters. At 'Erfurt, they are 

 used in the formation of artificial beds of cress, 

 which produce 12,000 a-year. In the north of 

 France, the reservoirs in which the flax is steeped 

 which is destined to be employed in the manufac- 

 ture of lace and the finer descriptions of linen, are 

 supplied by Artesian springs, whose waters, being 

 remarkably clear and of an equable temperature, 

 dissolve the vegetable matter with the least injury 

 to the most valuable properties of the plant. In 

 fish-preserves it is often found that the fish are 

 killed both by the severity of the winter and the 

 excessive heats of summer; but this effect of the 

 inequality of the seasons has been prevented at the 

 fish-ponds of Montmorency, near Paris, by furnish- 

 ing them abundantly with Artesian waters. 



ASPHALTE; a species of pitchy or bituminous 

 stone, which, in ancient times, was much used as a 

 cement in building (see the article Bitumen in the 

 body of the work), and which, of late years, has 

 been recommended to public notice, as excellently 

 adapted for covering floors, roofs, for flagging, and 

 for -various other useful purposes. Of its modern 

 revivication, we have the following account in 

 Chambers' Journal. 



On examining the valley of Travers, in the 

 Prussian province of Neufchatel, about the year 

 1712, an ingenious, learned, and speculative Greek, 

 named Eirinis, discovered a fine bed of asphaltic 

 rock, and, probably from some recollections sug- 

 gested to him by his knowledge of antiquity, be- 

 gan to make experiments upon the value of the 

 rock for cementing purposes. He describes this 

 rock, or asphalte, as he called it, to be " composed 

 of a mineral substance, gelatinous and calorous, 

 more clammy and glutinous than pitch ; not porous, 

 but very solid, as its weight indicates ; and so re- 

 pelling the influence alike of air, cold, and water, 

 that neither can penetrate it ; it is better adapted 

 than any other substance to cement and bind build- 

 ings and structures of every kind ; preserving the 

 timber from the dry rot, from worms, and the 

 ravages of time ; so much so, that exposure to the 

 most inclement extremes of weather only renders 

 it the firmer and the more enduring." Such is the 

 account given by Eirinis of his asphaltic cement ; 

 and he also states that its efficacy and durability 

 were tried and proved on many buildings in France, 

 Neufchatel, and Switzerland. " Nothing (says he") 

 can be easier than the composition of this cement, ' 

 and be gives directions for melting it as it is taken 

 from the mine, and stirring it when melted, mixing 



