Fig. 234.Plan of Wells at Longton.
Fig. 234.Plan of Wells at Longton.
Longton, Staffordshire.—The Potteries obtain a portion of their supply from a series of wells at Longton, which are shown in the diagrammatic sectional plan,Fig. 234. The well marked No. 1 is 12 feet in diameter, and 135 feet deep in the new red sandstone. When finished the water rose to within 35 feet from the surface. The cost of the first 45 feet was 3l.10s.a yard; of the second 45 feet, 6l.10s.a yard; and the third 45 feet, 9l.a yard. When this well was 36 feet down, a large quantity of water was met with, so a heading was driven at that depth in the direction of No. 2 well; this, after 30 feet, passed through a fault which drained off the water, and the sinking of No. 1 was proceeded with. After the engine had been erected and pumping some short time, it was proposed to drive headings from the bottom; but owing to the pumps taking up so much room inthe shaft, there was not space enough for sinking operations to be carried on, and No. 2 well was therefore sunk for convenience sake, at the cost of about 30s.a yard. When No. 2 was down 54 feet, a trial bore-hole 3 inches diameter was put down, and water rose in a jet about 3 feet high. The well was then continued to the level of No. 1, and a heading, 39 feet long, driven between the two shafts. No. 2 has now a 12-inch bore-hole at bottom, down 54 feet.
Fig. 235.Well at Bolckow and Vaughan’s, Middlesborough.Larger image(270 kB)
Fig. 235.Well at Bolckow and Vaughan’s, Middlesborough.
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Fig. 237.
Fig. 237.
Fig. 238.
Fig. 238.
Fig. 236.Well at Bolckow and Vaughan’s, Middlesborough.Larger image(284 kB)
Fig. 236.Well at Bolckow and Vaughan’s, Middlesborough.
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Headings have also been driven W. and N. of No. 2 well, at a cost of 30s.a yard. The western heading is 213 feet long, driven with a slight rise, and gave much water. There are two headings N., running in the direction of the railway, one over the other. The lower was driven level with the bottom of the shaft, but no water met with; the upper is 36 feet from the surface, and is intended to carry away surplus water down to a line of earthenware pipes which are led along the railway to a low-level reservoir.
In the eastern heading there is a rise of 4 feet, owing to the nature of the strata; and after it had been driven 510 feet, well No. 3 was sunk for ventilation and for drawing out material. A bed of very hard sandstone, 63 feet long, was passed, cost 4l.10s.a yard, and beyond came marl, in which driving cost 45s.a yard. This heading was continued 330 feet beyond No. 3, and an air-hole 3 inches diameter put down 126 yards deep, but no water was met with. The bed of hard sandstone was also found in driving the lower N. heading, which was discontinued after going into it some 5 or 6 feet. The yield from these wells is about 600,000 gallons a day, and recently a new bore-hole at No. 3 well, when down 350 feet, gave some 380,000 gallons a day additional.
Leek.—The Potteries waterworks have also wells at the Wallgrange Springs, near Leek; these rise from the conglomerate beds, and are stated to yield 3,000,000 gallons daily. The water from these springs is pumped into Ladderidge reservoir, and is distributed from thence into the town of Newcastle-under-Lyme and the Potteries.
Figs. 239, 240.Well at Ross, Herefordshire.Larger image(298 kB)
Figs. 239, 240.Well at Ross, Herefordshire.
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Middlesborough.—The Figs.235to238are sections and plansof a well at the works of Messrs. Bolckow and Vaughan, Middlesborough, made under the direction of S. C. Homersham, C.E. A trial hole was first put down to a depth of 398 feet 6 inches, and a shaft afterwards sunk by Messrs. Docwra and Son to that depth, through alternating beds of clay, sand, gypsum, and sandstone. At the bottom of the shaft a bore-hole of 18 inches diameter throughout was made with Mather and Platt’s apparatus to a depth of 1312 feet; the first 1160 feet of which were through new red sandstone interspersed with bedsof clay, white sandstone, red marl, and gypsum. Next came 40 feet of gypsum, hard white sandstone, and limestone; and the remaining 100 feet were through red sandstone, pure salt rock, occasional layers of limestone, and then salt rock to the bottom. The gross time spent in sinking this bore-hole was 510 days, or an average of 2 feet 5 inches a day.
Ross, Herefordshire.—The well at the Alton Court Brewery is shown inFigs. 239, 240. The shaft, 5 feet in diameter and 27 feet deep, is steined with 9-inch brickwork for a distance of 17feet. At the bottom is a 12-inch bore-hole 100 feet 9 inches deep, unlined. The water is abundant. At level of the bore a heading, 6 feet high, 5 feet wide, and 27 long, has been driven, to afford storage room.
Wolverhampton.—This town is partially supplied from wells sunk in the new red sandstone. There are two shafts, 7 feet in diameter and 300 feet deep, a heading 459 feet long, and in this a boring of 390 feet. The yield when first completed was 211,000 gallons a day.
Figs. 241, 242.Well At Swanage, Dorset.Larger image(329 kB)
Figs. 241, 242.Well At Swanage, Dorset.
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St. Helens, Lancashire.—Supplied with about 570,000 gallons daily from two wells, each 210 feet deep, in the new red sandstone. Each well has a bore-hole at the bottom.
Northampton.—The well at the waterworks is sunk and bored 253 feet 3 inches in the lias. The shaft is steined with brickwork and iron cylinders in the following order: for 16 feet 9 inches in depth the well is 7 feet 6 inches in diameter, lined with brickwork; at this depth two cast-iron cylinders 5 feet 6 inches diameter are introduced, which are again succeeded by 9-inch brickwork, commencing at 5 feet 6 inches internal diameter and widening out to 7 feet 6 inches in diameter. The bottom of the shaft is floored with bricks at a distance of 120 feet from surface. At this point the bore-hole commences, and for the first 31 feet it is lined with 14-inch pipes, which rise into theshaft 5 feet above the floor. The remaining portion of the bore-hole, 102 feet, is 9 inches diameter.
Swanage, Dorset.—The section and plan,Figs. 241, 242, are of a well at Swanage, sunk 60 feet and bored 53 feet, the lining tube rising 8 feet into the shaft, which is 5 feet 6 inches in diameter, and lined with 9-inch steining. The strata passed through are clays and limestones, and may perhaps be referred to the Purbeck beds. At first this well yielded little or no water, but it now gives a sufficient supply.
Bishop Stortford.—The waterworks and well are situate west of the town, near the farm buildings known as Marsh Barns. The shaft is 160 feet deep, the bore-hole 140 feet. The following is a section of the strata;—
Feet.Boulder Clay17London Clay, 54 feet;—Brown Clay14Black Clay2Black Sandy Loam, with iron pyrites12Black Clay, with lignite11Dark Grey Sand, with large pieces of sandstone and shells15Reading Beds, 451⁄2feet;—Black Clay2Brown Clay20Light Brown Sand01⁄2Variegated Sand18Brown Clay4Flints and Pebbles1To Chalk1161⁄2Chalk1831⁄2Total300
The water rises to within 140 feet of the surface of the ground. The yield is 10,000 gallons a minute; only 25 gallons a minute from the bore; the rest from the headings driven north and south respectively at a depth of 154 feet.
Braintree.—The well sunk for the Local Board is in a field near Pod’s Brook. The shaft is 8 feet in diameter, steined with 9-inch steining, and carried down 55 feet, the remainder of the well being bored. Strata;—
Drift, 14 feet;—Feet.Sandy Gravel5Drift Clay9London Clay, 136 feet;—Clay, with sand, shells, and septaria, the bottom part more sandy126Dark Sand, with a few shells, yielding much water10Reading Beds, 45 feet;—Mottled Plastic Clays, getting more sandy lower down, and with specks of chalk44Coarse Black Sandy Clay1Thanet Sand(?), 33 feet;—Light-coloured Sands, firm and hard, getting darker and more friable lower down20Light-coloured Sands, firm, changing to coarse and dark13To Chalk228Chalk, with much water, rising to about 12 feet from the surface17Total245
The level of the ground is 140 feet above the sea-level; water stands 29 feet deep; yield about 11,500 gallons an hour.
Brighton.—This town has always been supplied from wells sunk in the chalk. One well is sunk near the Lewes Road, and has a total length of 2400 feet of headings driven in a direction parallel with the sea, and at about the coast-level of low water. These headings intercept many fissures and materially add to the yield.
A second well was sunk in 1865, at Goldstone Bottom, and headings driven to the extent of about a quarter of a mile across the valley parallel to the sea.
Goldstone Bottom is a naturally formed basin in the chalk,the lowest side of which, nearest the sea, is more than 60 feet higher than the middle or bottom of the basin. The water is obtained as at Lewes Road, from fissures running generally at right-angles to the coast-line, but they are of much larger size and at far greater distances from each other; whereas at the Lewes Road well it is rare that 30 feet of headings were driven without finding a fissure, and the yield of the largest was not more than 100 to 150 gallons a minute. At Goldstone nearly 160 feet were traversed without any result, and then an enormous fissure was pierced which yielded at once nearly 1000 gallons a minute; and the same interval was found between this and the next fissure, which was of a capacity nearly as large. The total length of the headings at Goldstone Bottom is 13,000 feet. The yield from each well is about 3,000,000 gallons daily.
Chelmsford.—The well belonging to the Local Board of Health, situated at Moulsham, yields about 95,000 gallons of water a day. It is sunk for 200 feet; the rest bored. Water overflowed at first, but now that the well is in use and pumped from, the water only rises to 76 feet from the surface. The following strata were pierced;—
Feet. In.Black Soil(Mould)3 0Drift, 631⁄2feet;—Yellow Clay2 6Gravel12 6Quicksand44 6Sand, with stones4 0London Clay, 1861⁄2feet;—Clay104 0Clay, with sand50 0Dark Sand12 6Clay Slate (? septaria)0 9Clay and Shells4 0Clay Slate (? septaria)0 3Dark Sand and Clay9 6Sand and Shells4 0Pebbles1 6Woolwich Beds;—Sand7 0Red Clay12 0Clay and Sand64 0Dark Thanet Sand30 0To Chalk366 0Chalk, 202 feet;—Chalk88 0Rubble1 0Chalk113 0Total568 0
Cheshunt, New River Company.—Situate at the engine-house between the two reservoirs. The well is 171 feet deep, and is steined partly with brickwork and partly with iron cylinders. For 12 feet in depth the well is 11 feet 6 inches in diameter, and steined with 14-inch brickwork; for a farther depth of 44 feet it is 9 feet diameter, and steined with 9-inch brickwork; of the 44 feet, 41 feet are lined with cast-iron cylinders, 8 feet diameter, which are also carried to a depth of 105 feet from the surface. There are fifteen cylinders of this size in use, and they are succeeded by others 6 feet 10 inches diameter, of which there are six in use; these are again succeeded by two cylinders 6 feet diameter. The whole of the cylinders are 6 feet in depth. The bottom of the last cylinder is 118 feet from the surface, at which point they rest upon a foundation of 9-inch brick steining 7 feet in depth. At the bottom of the 6-feet cylinders the well widens out in the form of a cone 12 feet 6 inches diameter at the floor, which is 26 feet below the bottom of the 6-feet cylinder. In the centre of the well a bore-hole, 3 inches diameter and 27 feet deep, was made, and the well is provided on the floor-level with headings.
Section of Strata.Feet. In.Surface Earth1 6Gravel8 0London Clay, 47 feet;—Blue Clay45 0Yellow Clay2 0Reading Beds, 51 feet;—White Sand12 0Dark Sand39 0To Chalk107 6Chalk63 6Total171 0
Dorking, Surrey, obtains its water supply from a well sunk into the outcrop of the lower greensand, at the south side of the town. The shaft is 11 feet in diameter and 160 feet deep, steined with 9-inch work laid dry. The yield is not more than 30 gallons a minute, owing to the unfortunate position of the well, but might be considerably increased if suitable means were adopted.
Harrow Waterworks.—The well is situate 430 yards to the west of the church. The surface of the ground is 226 feet above the Ordnance datum. There is a shaft for 1931⁄2feet; the rest is a bore. In a bed of dark red sand 144 feet down, the water was very foul. Strata;—
Feet. In.Light Blue Clay, with light-coloured stone19 11Brown Clay, with white stone54 11Dark Mottled Clay15 0Similar Clay, with dark and green sand4 0The same, very hard3 0The same, very hard, and dark sand2 0Lighter-coloured Hard Clay5 0The same, and dark sand6 0Large Pebbles0 6Clay and Sand5 0Light Blue Clay0 4Light-coloured Stone, with red and blue spots1 3Mottled Clays7 11Yellow, Light Blue, and Green Clay1 0Dark Green Clay, with black veins and spots5 0Blue Clay1 6Very Hard Brown, Yellow, and Blue Clay4 0Light Brown Running Sand, with water2 6Hard Mottled Clays6 6Light Brown Dead Sand8 8Black Peat, with dark pebbles0 6Brown and Green Gravel, with flints3 2Green Clay0 4To Chalk158 6Chalk, with beds of flint 4 to 15 inches in thickness, 15 to 24 inches apart; 3951⁄2feet down, from surface, a bed of flint 6 feet thick254 0Total412 6
Water rises to a height of 125 feet below the surface. The yield is about 190 gallons a minute.
Figs. 243-245.Well at Highbury.Larger image(366 kB)
Figs. 243-245.Well at Highbury.
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Highbury, Middlesex.—Well at the residence of H. Rydon, Esq., New Park.Figs. 243 to 245. The shaft is 4 feet 6 inches diameter, and 136 feet deep, steined with 9-inch work set in cement. The bore was commenced with a 12-inch hole, but the character of the ground was such that the successive reductions in size, shown in the enlarged section of the lining tubes,Fig. 245, had to be made. When in the chalk the bore was continued some 48 feet unlined. The strata passed were;—
Gravel3feet.London Clay, 111 feet;—Blue Clay110„Claystone1„Reading and Thanet Sand, 85 feet;—Mottled Clay25„Coloured Sand60„To Chalk199„Chalk50„Total249„
Kentish Town.—This well was sunk under the supposition that as the outcrop of the subcretaceous formations was continuous around the margin of the cretaceous basin surrounding and underlying the London tertiaries, except at the eastern border, those subcretaceous formations would be found under London, just as they actually were at Paris. This proved to be the case until the gault was passed, when a series of sandstones and clays was encountered, occupying the place of the lower greensand, but evidently of older geological character, and having many of the features of the new red sandstone.
Figs. 246, 247.Boring at Kentish Town, London.
Figs. 246, 247.Boring at Kentish Town, London.
The surface of the ground,Fig. 246, is 174 feet above Thames high-water mark. There is a shaft for 539 feet; the remainder being bored. The following detailed account of the strata is due to Prestwich.
Figs. 248, 249.Boring at Kentish Town, London—continued.
Figs. 248, 249.Boring at Kentish Town, London—continued.
London Clay, 236 feet;—Feet.In.Yellow Clay306Blue Clay, with septaria2056Reading Beds, 611⁄2feet:—Red, Yellow, and Blue Mottled Clay376White Sand, with flint pebbles06Black Sand, passing into the bed below20Mottled Green and Red Clay10Clayey Sand30Dark Grey Sand, with layers of clay96Ash-coloured Quicksand66Flint Pebbles16Thanet Sand, 27 feet;—Ash-coloured Sand100Clayey Sand40Dark Grey Clayey Sand110Angular Green-coated Flints20Chalk, with Flints(?Upper Chalk), 2441⁄2feet;—Chalk, with flints1196Hard Chalk, without flints80Chalk, softer, with a few flints316Nodular Chalk, with three beds of tabular flints136Chalk, with layers of flint326Chalk, with a few flints and patches of sand96Very Light-grey Chalk, with a few flints300Chalk, without Flints(Lower Chalk), 341 feet;—Light Grey Chalk, and a few thin beds of marl1330Grey Chalk Marl, with compact and marly bedsand occasional pyrites1610Grey Marl200Harder Grey Marl, rather sandy and withoccasional pyrites270Chalk Marl, 591⁄4feet;—Hard Rocky Marl (? Tottenhoe Stone)06Bluish Grey Marl, rather sandy, lower part more clayey589Upper Greensand;—Dark Green Sand, mixed with grey clay139Gault, 1301⁄2feet;—Bluish Grey Micaceous Clay, slightly sandy390The same, with two layers of clayey greensand67Micaceous Blue Clay; at base a layer full ofphosphatic nodules8411Lower Greensand(?), 1881⁄2feet;—Red and Yellow Clayey Sand and Sandstone10Compact Red Clay, with patches of variegated sandstone40Dark Red Clay47Red Clay, Whitish Sand, and Mottled Sandstone30Hard Red Conglomerate, with pebbles from thesize of a marble to that of a cannon-ball20Micaceous Red Clay, mottled in places260Layers of White Sandstone and Red Sand38Mottled Sandstone04Red Sand and Sandstone, with pebbles (a spring)20Layers of Red Sandstone and White Sand40Pebbly Red Sand and Sandstone10White and Red Sandstone50Fine Light Red Sand29Hard Sandstone03Very Fine Light Red Sand40Red Clay20Clayey Sand13Red Sandy Micaceous Clay, with sandstone25Compact Hard Greenish Sandstone100Very Micaceous Red Clay10Grey and Red Clayey Sand11Light-coloured Soft Sandstone21Red Sand and Sandstone62Greenish Sandstone40White and Grey Clayey Sand, with iron pyrites20Reddish Clayey Sand, with layers of sandstone38Micaceous Red Clay184Greenish Sandstone05Red Mottled Micaceous Clay, with patches of sand346Red Quartzose Micaceous Sandstone20Brownish-red Clayey Sand and Sandstone40Very Hard Micaceous Sandstone, with pebbles ofwhite quartz40Light Red Clayey Sand100Red Micaceous Quartzose Sandstone80Light Red Clayey Sand, small fragments of chalk20Whitish and Greenish Hard Micaceous Sandstone60Total13020
The engravings, Figs.246to249, which are on the authority of G. R. Burnell, do not exactly agree with Prestwich’s section, but in the main they are both alike. The following summary may be found of service;—
Feet.In.London Clay2360Lower London Tertiaries886Chalk6449Upper Greensand139Gault1306Lower Greensand (?)1886
Fig. 250.Well at Michelmersh.
Fig. 250.Well at Michelmersh.
Michelmersh, Hants.—Fig. 250shows a section of a well in this village, comprised within the writer’s practice. The shaft is 4 ft. 6 in. in diameter and 400 feet deep, steined both above and below the chalk with 9-inch work, the upper course having rings of cement at every 12 inches.
The strata pierced were;—
Feet.In.Surface Soil40Dark Clay270Chalk2500Band of Calcareous Sand26Upper Greensand170Total3006
The water rises some 19 feet in the shaft, and is abundant, although up to the present its quantity has not been tested.
Mile End, Middlesex.—Well at Charrington, Head, and Co.’s brewery.Figs. 251 to 253. The surface is 331⁄2feet above Trinity high-water mark.
In the upper part there are three iron cylinders built upon9-inch brickwork, which is carried down into the mottled clay. A 9-inch iron cylinder, partially supported by rods from the surface, rises some 28 feet into the brick shaft into which it is built by means of rings. Another iron cylinder is carried down into the chalk, the space between the cylinders being filled in with concrete.
The strata passed were;—
Feet.In.Made Earth70Valley Drift, 6 feet;—Sand30Gravel30London Clay, 86 feet;—Blue Clay70Hard Brown Clay, with claystones680Brown Sandy Clay20Hard Brown Sandy Clay, rotten at bottom90Woolwich and Reading Beds630Thanet Sand, 40 feet;—Green Sand20Brownish-green Quicksand and Pebbles20Brown Sand20Grey and Brownish-green Sand20Green Sand and Pebbles20Brown Sand20Green Sand and Pebbles150Grey Sand and small Pebbles20Dark Grey and Green Sand106Green Sand and Green-coated Flints06To Chalk2020Chalk Flints06Hard Chalk and Water20Total2046
The water-level is some 103 feet from surface, and the yield 60,000 to 70,000 gallons a day.
Figs. 251-253.Well at Charrington’s, Mile End.Larger image(280 kB)
Figs. 251-253.Well at Charrington’s, Mile End.
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Norwich.—Well at Coleman’s works. After a few feet of alluvium the borer passed through hard chalk with flints at distances of about 6 or 7 feet apart, for 700 feet, with the exceptionof 10 feet at the depth of 500 feet where the rock was soft and of a rusty colour, thence the flints were thicker, namely, about 4 feet apart to the depth of 1050 feet. After this 102 feet were pierced of chalk, free from flints, to the upper greensand, a stratum of about 6 feet, and then gault for 36 feet. The whole boring being full of water to within 16 feet of the surface.
Section of strata;—
Feet.Alluvium12Hard Chalk, with flints483Soft Chalk10Hard Chalk190Hard Chalk, flints closer350Chalk without flints102Upper Greensand6Gault36Total1189
Paris.—The wells sunk in the Paris basin, of whichFig. 254is a section, are very numerous, and many of them of great depth.Fig. 255is a plan indicating the position of the principal wells, andFigs. 256 to 258sections giving each a summary of the nature and thickness of the formations passed through.
Fig. 254.Geological Section from Niort to Verdun, through the Paris Basin.Horizontal scale, 90 miles the inch.Vertical scale, 1500 feet the inch.Larger image(201 kB)
Fig. 254.Geological Section from Niort to Verdun, through the Paris Basin.Horizontal scale, 90 miles the inch.Vertical scale, 1500 feet the inch.
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For boring these wells special tools had to be used, which have already been described at length in Chap. VI.
A large Artesian well was, in 1867, being constructed by Dru at Butte-aux-Cailles,Fig. 255, for the supply of the city of Paris, which is intended to be carried down through the greensand to a depth of 2600 or 2900 feet to reach the Portland limestone. The boring in 1867 was 490 feet deep, and its diameter 47 inches.
During the previous 21⁄2years, M. Dru was engaged in sinking a similar well of 19 inches diameter for supplying the Sugar Refinery of M. Say, in Paris,Fig. 255; 1570 feet deep of this well had been bored in 1867, seeFig. 258.
The well at Grenelle was sunk by Mulot in 1832, and after more than eight years’ incessant labour, water rose on the 26th of February, 1842, from the total depth of 1806 feet 9 inches. The diameter of the bore-hole is 8 inches, ending, as is seen in the detail sections, Figs.259to262, in the lower greensand.
The well of Passy was intended to be executed in the Paris basin which it was to traverse with a diameter, hitherto unattempted, of 1 mètre (3·2809 feet); that of the Grenelle well being only 20 centimètres (8 inches). It was calculated that it would reach the water-bearing stratum at nearly the same depth as the latter, and would yield 8000 mètres or 10,000 cubic mètres in twenty-four hours, or about 1,786,240 gallons to 2,232,800 gallons a day.
Figs.263to266show a detail section of the strata passed.