304 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[Oct. 



tact with the air, and mixing up the sedimentary deposits. — The subject 

 excited considerable attention, and many gentlemen joined in the conversa- 

 tion, all of Ihem adducing additional evidence of the importance of in- 

 vestigating the coudilioD of water supplied to large towns. 



Section C. — Geology. 



Prenidmt: Mr. L. Horner.— IVce Presidents.- The Dean of Westminster, 

 Sir H. T. Ue la Heche, Dr. W. 11. Fittoii, Mr. \V. Hopkins, fFor Ceo- 

 graphtj) Mr. G. li. GreenhouKh.— SecrWaWes; Mr. R. A. Austin, Prof. 

 Oldham, Mr. J. II. Norton, (For Geography) Mr. C. T. Beke.— C'om- 

 mitiee: I'rof. Agassiz, Prof. Ansted, Mons. Le Blanc, Major Gierke, 

 Messrs. C.Darwin, Duncan, Prof. E. Forbes, Mr. G. W. Featherstonhaugh, 

 Mons. Graves, Messrs. R. Hutton, \V. J. Hamilton, Capt. Ibbetson, Mr. W. 

 King, Mons. dc Koninck, Mr. C. Lyell, Prof. Von Middendorf, Mr If. Mal- 

 let, Marquis of Northampton, Mons. de Pinteville, .Messrs. W. Sanders, 

 W. Sbarpe, Rev. Mr. Walker, Mr. J. Yates, Lieut.-Col, Colbr, Messrs. G. W. 

 Ormerod, J.Phillips, Sir P.de M. G. Egerton, Dart., Dr. Pye Smith, Hon. 

 and Rev. C. Harris, Mr. J. 13. Jukes, Capt. James. 



" On the Artesian Well on the Southampton Common." Bv U. Keelk, 

 Esq. — The town of Southampton has hitherto dei)ended for a supply of fresh 

 water to private wells, which are attached to almost every house. They are 

 sunk through a bed of gravel, and vary in depth from 10 to 20 or 25 feet,— 

 at which depth the London clay is reached. An uncertain quantity has also 

 been obtained from the public VN-ater-works, supplied by land springs. These 

 sources being insufficient for a growing town, with 30,000 inhabitants, other 

 njodes of supply have long been contemplated. The river Test was con- 

 sidered too distant ; and the commissioners could not accede to the terms 

 proposed by the proprietor of the most convenient part of the river Itchen. 

 lu November, 1835, Mr. Clarke, of London, made an experimental boring 

 on the Southampton Common, through 80 feet of alluvial strata, 300 feet of 

 London clay, and about 100 feet of plastic clay ; and afterwards the boring 

 was extended 50 feet into the chalk. The supply was ample ; and an Act 

 of Parliament was obtained for providing the means necessarv to construct 

 a well which should supply 40,000 cubic feet of water daily. Mr. Clarke 

 estimated the expense at i/.OOO. In 1837, a contract was made with Mr. 

 Collyer, who proposed to sink an iron cylinder, having a diameter of thir- 

 teen feet, to the depth of 160 feet, and from that point to bore to the fur- 

 ther depth of -100 feet, commencing with a bore of 30 inches, and graduallv 

 diminishing to one of 20. The estimate amounted to £9,980. The cyliu- 

 der was found inefficient ; and a brick shaft, of 14 feet diameter, was con- 

 tinued to the intended depth of ICO feet. Two pumps were employed to 

 raise the water, which amounted to 4,000 cubic feet per diem. Here, in- 

 stead of commencing the boring, the brick shaft was carried on, by advice 

 of the consulting engineer. At the depth of 164 feet, the diameter of the 

 shaft was reduced to 1 1 ft. G in. At this period, the candles could scarcely 

 be kept lighted ; and an air-tube of zinc, with a pair of bellows worked by 

 the steam-engine, was attached, for the purpose of ventilation. Masses of 

 limestone, five or six tons in weight, had frequently to be raised. There 

 was a considerable escape of gas from the sides and bottom of the well, 

 which, together with the vapour that filled the shaft and the impure air 

 caused by so luany men at work, occasioned some alarm. At the depth of 

 214 feet, the shaft was reduced to 10 feet in diameter; and at the depth of 

 270 feet, to 8 feet G inches. The work was then suspended till more pow- 

 erful pumps could be obtained. On emptying the shaft, and deepening it 

 23 feet, the influx of water became so great that iron cylinders, 7 feet in 

 diameter, were again resorted to, instead of brickwork. At 322 feet the 

 brick shaft was resumed; the quantity of water raised bv the engine 

 amounted to 30,240 gallons in twenty-four hours. At 380 feet from the 

 top of the well, the plastic clay was reached, and the brick shaft continued 

 through it to the chalk. Little or no sand or water was found in the plastic 

 clay. The work w.is continued day and night till December 4. 1841, when 

 the shaft was 520 feet deep; about three gallons of water flowed into it per 

 minute, its temperature at the bottom ranging from 61° to 62° Fah. The 

 atmosphere of the well at 50 feet was 54°; at 160 feet, 60°; at 543 feet, 

 G5°. The temperature of water at the surface was 44". In March, 1842, 

 the shaft measured 562 feet ; and the pumping having having been suspended 

 for a week, the water rose 400 feet, amounting in quantity 'to 21,578 cubic 

 feet. Tins supply being insufficient, the contractors commenced boring with 

 a 7J-inch augur, attached to a rod, conducted to the bottom of the shaft by 

 an iron tube, fixed in the centre of the well. The total depth of the shaft 

 and boring amounts to 1260 feet; and at the time the boring was suspendeil 

 the water rose to within 40 feet of the surface. In 1 845, during upw.irds of 

 four months' daily pumping, the delivery of water was at the rate of up- 

 wards of 1,500,000 gallons per month; and afterwards, in eight davs, the 

 quantity raised exceeded 725,000 gallons . When the pumping was discon- 

 tinued in November, 1845, the water rose, as before, to within 40 feet of the 

 siu-face. 



Mr. Hopkins, in reply to questions as to the advantage of continuing the 

 operations, and the probable supply, stated that the example of the artesian 

 well at Crenelle was calculated to give confidence in similar undertakings 

 where a general analogy existed. The comparison, however, between Paris 

 and Southampton was not complete. Paris was in the verv centre of a ter- 

 tiary, and probably over the deepest part ; the water flowed to it in all di- 

 rections ; the inclination of the beds, too, was gentle ; and there were no 

 dislocations. Here, however, the chalk of North Hampshire inclined gradu. 



ally towards the sea, and, passing under it, rose again, with a much greater 

 inclination, in the Isle of Wight. There was no reason for supposing that 

 Southampton was situated over the lowest part of this basin ; and since, in 

 the Isle of Wight, there was an enormous dislocation, there might be other 

 dislocations or fissures in the intermediate space, which might afford an out- 

 let for the water below. The height to which water would rise in an arte- 

 sian well would be affected by the construction of other wells in its neigh- 

 bourhood. The first artesian well at Cambridge rose 15 feet above the sur- 

 face, but other wells had reduced its height to 4 feet below the surface. The 

 borings in these instances were only 4 or 5 inches in diameter; but the sup- 

 ply was large, and independent of the eristence of any large caverns or fis- 

 sures. The water came from the iron sands below the gault clay ; it had a 

 sUghtly ferruginous taste, but was quite good. No water was obtained in 

 the chalk, nor could an artesian well be expected in that formation, which 

 is too permeable to hold water. In conclusion, Mr. Hopkins said that he 

 should himself recommend the continuation of the boring, as the trial was 

 not complete till the beds below the chalk were reached. 



Mr. Greenuoigh remarked on the extent of the dislocation which ex- 

 tends through the centre of the Isle of Wight. He believed geologists had 

 done more good by discouraging hopeless speculations than by encouraging 

 useful experiments ; and they would not give a positive recommendation, 

 except from experience. He alluded to the artesian wells of Lincolnshire, 

 in a district before scarcely habitable, on account of the scarcity of fresh 

 water, and the thickness of clay impervious to water. Porous beds, resting 

 upon others which were not porous, could alone afford a supply of water. 



" On the Origin of the Coal of Silesia." By Prof. Gobppert, of Brcslau. 

 This paper was an abstract of an essay which received the prize offered by 

 the Society of Sciences of Holland, at Haerlem, in 1844. Prof. Goeppert 

 remarks, that hitherto few well-preserved plants had been obtained from the 

 coal itself, but its composition had been inferred from the plants which lie 

 in the associated shales. In the coal-fields of Upper and Lower Silesia, 

 which yield four millions of tons a year, he had met with extensive layers, 

 in which the plants were so well preserved, that he could distinguish coal 

 formed from Sigillaria; from that formed by .\raucaria; or Lepidodrendra. In 

 most instances the bark alone was preserved — the specimens being flattened ; 

 but the Araucaria;, being much harder than the rest, often retained their 

 woody tissue and medullary rays. The species, 80 in number, were found to 

 be differently grouped in the various coal strata, and also under different 

 conditions ; and this, with the delicate preservation of the ferns, the multi- 

 tude of upright stems, of which 200 have already been observed, and the 

 uniform thickuess of the strata over a space of many miles, are considered 

 by the author a proof of tranquil deposition on the present localities. The 

 Silesian coal strata are from 30 to 60 feet thick ; a larger portion of which 

 M. Goeppert supposes to have accumulated after the manner of peat, during 

 the lapse of time. He has ascertained that, by keeping vegetables in boiling 

 water for three months or a year, they are converted into brown coal (lig- 

 nite), and, by the addition of a smaU quantity of sulphate of iron, a salt 

 which occurs commonly in coal, acquire, a; last, a totally black, coal-like 

 condition. 



Sir R. I. Mi'RCHisox expressed his readiness to receive this explanation 

 for the origin of many extensive coal strajo. There were other large coal- 

 fields to which the explanation would not apply at all, the materials having 

 certainly been drifted to a distance by currents of water. 



Mr. J. Phillips retuarked, that although even fragments of coal-plants 

 were uncommon in the coal of England, yet, with the aid of the microscope, 

 coni/eroiis tissue might be detected in much of the fibrous coal, which dif- 

 fered only in being less bituminous than the rest. In the ashes of coal, sili- 

 ceous casts of vegetable tissue were always to be found ; and Mr. Bower- 

 bank had detected traces of structure on the fractured surfaces of ordinary 

 solid coal. 



SECTION F.— Statistics. 



President: Jlr. G. R. Porter. — Vice-Presidents: Sir V. Lemon, Colonel 

 Sykes, Messrs. Hey wood, E. Nightingale. — Secretaries: JMessrs. W. 

 Cooke Taylor, J. Fletcher, F. G. P. Neilson, Rev. T. L. Shapcott. — Com- 

 mittee : The Mayor of Southampton, Messrs. W. Duckworth, H. Hallam, 

 M. PhiUips, .M.P., M. Ricardo,J. C. Sbarpe, J. Shuttleworth, T. Tooke, 

 G. S. Kenrick, Dr. King, Mr. M. MUnes, JI.P., Capt. Allen, Rev. Prof. 

 Elton. 



Among the papers read was " yi Jteview of the Mines and Mining Industry 

 of Belgium." By R. Valpy, Esq., of the Board of Trade. It stated that, as 

 a coal-producing country, Belgium ranked the second in Europe. The 

 ratio of the coal district to the total area is 



Tons 

 Acres. annually. 



Great Britain ^, or 2,930,000 producing 34,000,000 



Belgium jiji or 335000 „ 4,500,000 



France -rns> "^ 630,000 „ 3,783,000 



Germanic Union 3,000,000 



In 1838 the total number of coal-mines in Belgium was 307, with 470 pits 

 in work, and 172 in process of construction, employing 37,171 persons; 

 being an increase of 8,454, or 28 per cent, on the number employed in 1829. 

 The increase of the quantity of coal raised was not accurately ascertained, 

 but it appeared to be about 37 per cent. The average cost of production is 

 10s. 8d. per ton, and theaverage price 23s. Id. forfirst quality, and IGs 6id. 



