THE ANALYST. FEBRUARY, 19U4. PROCEEDINGS OF THE SOCIETY OF PUBLIC ANALYSTS. ON THE SALINITY OF WATERS FROM THE OOLITES. BY W. W. FISHER, M.A., F.I.C. (Read at the Meeting, November 4, 1903.) THE waters described in this paper are obtained from the several geological formations grouped together as ‘ I oolites,” and comprising the following main divisions down- wards : 1. Kimmeridge Clay. 2. Corallian Oolite. 3. Oxford Clay and Helloway Rock. 4. Cornbrash, Forest Marble, and Great Oolite. This group of deposits extends in a broad strip entirely across England from the south coast of Devon and Dorset to the north-east coast of Yorkshire, but the waters here described are mainly from the districts near Oxford and the counties adjacent. During the past twenty years a great variety of samples have been examined, and probably the types of waters found in the oolites of this district will be found under similar conditions in other localities.Great OoZiie.-From the great oolitic limestone beds of the Cotswolds rise many magnificent springs of a high degree of organic purity, forming the head waters of the river Thames and its tributaries. The general charactere of these waters are well known, and examples of oolitic spring-waters are shown in Table I. It will be seen that the total dissolved mineral and saline constituents are about 20 grains per gallon, or even less ; the chlorides are small ; there is little or no ammonia ; while the proportion of organic matter is extremely small. Nitrates, however, are variable in amount, according t s the cultivation of the land adjacent to the springs, and often reach a substantial quantity.Broadly speaking, these spring-waters resemble spring-waters from the chalk in composition and character, and for similar reasons, being derived from limestones porous in character, from which the more soluble constituents have long ago been washed out by percolation, the dissolved solids are mainly calcium carbonate, with small quantities of magnesium and alkaline sulphates and chlorides.TABLE I.-WATERS FROM GREAT OOLITE SERIFJS (UNCOVERED BEDS). (Analysis iiz Grains per Gallon; 1 G'allon = 70,000 Grains.) ininoid Ammonia. NO. 3,779 1,064 2,307 2,460 2,533 2,636 3,011 2,960 2,850 3,738 3,833 1,280 3,196 3,385 3,355 2,093 2,392 2,446 4,360 3,076 3,904 3,040 3,897 3,661 3,666 3,680 - absorbed, ctc.Three Hours. Locality. Near Bibury, Glos., Kitrbrook, Oxon Near Moreton-in-Marsh, Near Moroton-in-Marsh, Chipping Norton, Oxon Over Norton, Oxon Fullbrook, B u r f o r dy Burford, Oxon Brize Norton, Oxon Leafield, Oxon Brac kley , Nort hsn t s Charlbury, Oxon Bradwell, Burford, Oxoti Witney, Oxon Woodstock, Oxon Middleton, near Bices- Middleton, near Bices- Gowell, near Bicester, Bicester, Oxon Fringford, Oxon Stratton Audley, Oxon, Newport Pagnell, Bucks Stony Stratford, Bucks Buckingham, 1901 Upper Colne River Glouces ter Glouces ter Oxon $ 3 Y, ter, Oxon ter, Oxon Oxon new boring Depth in Feet. __ ~- Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring Spring 70 80 30 50 66 120 112 120 130 50 301 301 301 - - - Total Solids.19.0 18.0 18.2 19.8 21.0 18.0 20.1 20.4 25.5 32.0 37.5 21.0 21.3 22.1 54.0 22.1 26-0 32.0 26.6 26.8 25-0 36.4 32.2 38-9 60 0 68.7 30.0 Chlorine in Chlorides. 0.7 1.1 0.8 1.0 0.8 0.77 0.9 0-8 0.9 1 *1 1 .o 1.2 0.9 1.1 3.0 1.0 1.15 1.5 1.1 1.3 1.1 2-4 1.4 2.0 8.2 10-0 2.0 Saline Nitrogen 0.147 0.003 0.07 0.35 0.02 0-322 0.014 0.31 0-315 0.462 0.203 0.140 0014 0-35 0.25 0.05 0.08 0.014 0.021 0.014 0.04 0.07 0.02 0.203 0.45 0.014 0 014 0.014 0.001 0.001 0.001 0.002 0.001 0,004 0.002 0.002 0.001 0.008 0.019 0.0 0.001 0 a02 0.003 0.023 0.014 0.028 0.005 0.001 0.051 0.0 0.005 0,017 0.016 0.021 0.002 0.001 0.003 0.003 0-004 0.001 0.004 0.003 0.004 0.00 1 0.008 0.010 0.004 0.005 0.005 0.010 0-004 0.004 0.003 0.006 0.003 0.004 0.006 0.003 0 001 0.002 0.002 _____ 0.014 0.037 0.007 0.005 0.013 0-005 0-005 0.002 0 006 0.005 0.040 0.017 0.01 1 0.013 0.014 0.036 0.003 0.013 0-007 0.026 0.020 0.0 0.010 0 012 0-016 0.016 0.015 Remarks.Discharges 400 gallons per minute Part of town supply Village supply 9,000 gallons daily Northampton sands * Z b H L' New town supply 10 3 m Overflows at surface. New supply to town Overflows at surface Rises 17 feet above sur- face. See Table VII. Beginning of pumping Seven days later Seven days later, after continuous puniping testTABLE II.-WATERS FROM OOLITES BELOW OXFORD CLAY. (Analysis in Grains per Gallon.) No. 454 2,528 3,931 2,791 4,160 3,027 2,774 2,811 4,151 3,517 Locality. Witney Oxford City, new bor- ing, 1898 Inglesham, near Lech- lade Langford, near Bices- ter, 1898 Langford, near Bices- ter, February, 1903 Ambrosden, Oxon, ‘6 boiling well ’’ Oddington, Oxon, 1898 Merton, Oxon, new well, Marsh Gibbon 1899 Grendon Underwood Depth in Feet.270 400 290 87 87 over- flows 67 46 100 ? 20 ? Total Solids. ~- 308.0 672.0 1000*0 57.0 32.0 50.0 300.0 68.0 53.2 360.0 Chlprinc in :hlorides. 60.5 173.6 603.4 2.3 3.3 4.2 67.8 15.2 5-3 118-3 Nitrogen in Nitrat&. 0.025 0.0 0.0 0.05 0.02 0.07 0.014 0.21 0.014 0.021 Saline Ammonia. 0.063 0.101 0.462 0.042 0.023 0,007 0.089 0.008 0.020 0.042 Albu- niinoid Ammonia. 0.003 0.045 0.008 0.007 0.003 0.022 0.006 0.022 0.005 0.005 Oxygen ,hsorbed, etc., I‘hree Hours. 0-035 0.394 0.140 0.041 0-003 0.500 0.062 0.154 0,253 0.026 Total Hard- ness. Remarks. See Table VII. See Table VII. I3 El Overflows at surface.. ‘ 2 a1 k aline Overflows at surface. + F l-4 See Table VII. Water brown, peaty, m alkaline, nearly sterile. 9 See Table VII. Alkaline sulphates and carbonates Residue slightly alkaline. Water rises to surface Overflows. Peaty, alka- line, nearly sterile. See Table VII. Soft alkalinew Is TABLE III.-wATEHS FROM KELLOWAY BEDS AND OXFORD CLAY. (Analysis in Grains per GaZlon.) I Albu- / Oxy en minoid labsorbet etc., Ammonia. 1 Three Hours. Chlprine in Chlorides Total Hard- ness. Oxygen tbsorbed, etc. Three Hours. Nitrogen in Nitrates. Total Hard. ness. - - - - - - - Depth in Feet. 14 30 Spring 16 30 56 33 30 - hlbu- niinoid Ammonia. 0.007 0.018 0.032 0.010 0 GO4 0,044 0.020 0.005 0.021 0.015 Total Solids. 753.0 241.0 145.0 238.0 159.0 237.0 139.0 144 a 0 231.0 Saline Ammonia.0.005 0.07 0.127 0.015 0.057 0.035 0.074 0*001 0081 0.001 Remarks. Locality. No. 2,360 1,420 1,802 2,870 2,678 2,784 3,735 3,615 1,809 2,229 Woodham, Bucks Twyford, Bucks, trial Charndon, Bucks Clsydon, Bucks Little Chesterton, Oxon Oakley, Oxon Stratton Audley, Oxon Weston-on-Green, Oxon Newton Longville, Newton Longville, boring Oxon Oxon 90-3 23.4 7.0 5.9 2 *o 25.3 4.1 1.8 4.6 2.0 0 a064 0.133 0.221 0.030 0.024 0.222 0.177 0.038 0.046 0.099 See Table VIII. Much CaSO, 0,035 0-035 0.07 0.021 0.021 0-45 0.03 0.014 0.077 0.014 Much CsSO, See Table VII. Near edge of clay Trial boring I 44*0 I Trial boring M ?allon = 70,000 &aim. ) b --_--__-___ z TABLE IV.-WATERS FROM CORALLIAN OOLITE (UNCOVERED BEDS). (Analysis in Grains per Gallon ; 1 Depth in Feet.~- ~. Spring 16 - - - - 30 30 Spring 35 50 Spring 30 56 40 I NO. Remarks. Locality. I -~ I I 0 09 0.0 0.014 1 0.007 0.30 1 0.003 0.24 1 0.005 0.1 4 1 0.0 Hinksey, Berks Bofley, Berks Rodbourn, Berks Horton, Oxon Headington, Oxon Stanton St. John, Oxon Headington, Oxon Melksham , Wilts Near Littlemore, Oxon Shotover, Oxon Fariagdon, Berks Holton, Oxon Kingston, Berks Kennington, Berks Cowley, Oxon 0-013 0.006 0.012 0.0 0.015 0.037 0.024 0.006 0.019 0-002 0.002 0.004 0.006 0.007 0.003 0.010 0.003 0.006 1,385 I, 366 1,919 1,687 1,623 1,604 2,117 2,161 2,422 2,581 2,236 2,948 3,077 3,907 4,033 4,079 32-5 1 1.7 I 0.06 ' 0.006 32-0 63-0 29.4 31.0 27.7 35.0 30.0 47.0 41.0 31.0 0 -001 0.001 0.007 0.006 0.02 0.31 0.21 0.014 0-94 0.196 0.210 0.02 1 0.51 I 0.01 2.8 1.0 1.2 1.3 1 *8 1 2-3 j 1.4 1 1.2 1 2.0 0-004 0.020 18.8 New boring 0.005 I 0.004 0.007 0.003 1 0.006 0.014 0.001 I 0.006 0.035 0004 ' 0.005 0 014 0.011 , 0007 0.039 0.010 i 0.003 0.015 i - Hard.New well __-_ -___ Cumnor, Berks 30TABLE V.-WATERS FROM CORALLIAN OOLITE BELOW KIMMERIDGE CLAY. (Analysis in Grains per Gallon.) -~ NO. Depth in Feet. Chlorine in Chlorides, Nitrogen In Nitrates . 0.028 0.812 0.112 0.056 0.021 0-70 0.01 0.014 0-035 0.014 0.021 Albu- minoid Ammonia. Oxy en absorbei, etc., Three Hours. ~~ ~ _ _ _ 0.020 0.097 0.074 0.034 0.026 0.063 0.033 0.011 0,048 0.023 0.047 Total Solids. ___- 52.1 100.0 76.0 72.0 150.0 216-0 44.0 71-0 41.7 21.8 98.0 Saline Amnion ia. ~ - __ 0.04 0.004 0.002 0.055 0.077 0 ~005 0.070 0.004 0.005 0.017 0.061 Locality.Remarks. Burcote, Oxon W at bridge, Bucks Westcott, Bucks Near Cuddesdon, Oxon Bourton, Berks Near Swindon, Wilts Denchworth, Berks 190 16 185 265 70 180 50 190 260 230 - 5.8 6.6 1.4 3.3 43.4 7-5 4.2 1.4 2.8 1.3 26.0 2,339 2,361 2,907 2,940 3,624 3,408 3,372 3,195 4,112 4,045 4,199 0.001 0.021 0.010 0.006 0 *005 0.010 0.005 0.005 0.012 0.004 0.008 Alkaline residue Hard. CaSO, Hard. CaSO, Soft, alkaline residue See Table VII. Much CaSO, Alkaline carbonate and sulphate Hard. CaSO, Hard. See Table VII. See Table VII. See Table VII. Shrivenham, Berks Baldon, Oxon Cuddesdon, Oxon Swindon, Wilts TABLE VI.-WATERS FROM KIMMERIDGE CLAY. (Analgsis i i ~ Grains per Gallon,) .G Depth in Feet. Chlyrine in Chlorides. Nitrogen in Nitrates. Albn- n~ i iioid Ammonia. , Oxygen ~ Total absorbed, etc., ' Hard Three Hours.I ness. Total Solids. Saline Ammonia. 0,014 0 003 0.086 0.005 0.043 0.294 0.01 7 Locality. Remarks. NO. 25 12 77 12 43 22 - 1.0 10.1 8.8 1.2 1.6 16.0 17.7 0.006 0 -006 0.017 0.007 0.005 0.200 0.013 -- 0.04 0.42 0-035 0.014 0.014 0.028 0.021 0 -058 0.025 0.106 0.037 0.021 0.260 0.131 Baldon, Oxon Whitchurch, Bucks Garsington, Oxon Whitchurch, Bucks Garsington, Oxon Near Brill, Bucks Shotover, Oxon 37.0 174-0 140.0 96-0 134-0 292.0 213-0 1,267 2,833 2,959 3,682 3,190 3,814 3,869 Hard. CaSO, Hard. CaSO, Hard. CaSO MgSO,. See table VII. CaSO, cw CWw cp Witney, 1 Oxford, I Gowell, I TABLE VII. (In Grains per Gallon.) ' Lang- 1 Am- Stratton ford. brosden, Audley, 3,027. j 3,904. __~- Stra tton Audley, 3,735. __I Marsh Gibbon 4,151.5.3 6.05 14.01 2-31 0.73 ? - 8-73 10.74 27-44 - 1.53 4.13 ? -. Brill, 3,814. Swindon, 4,199. -- 26.0 3-65 3 8-63 1-40 1.01 -- - - 42.84 5.75 39-52 - 2.12 2.50 2.10 94-83 - Locality No. Bourton, 3,624. Baldor 4,112. -- 2-8 11.25 6-62 12.78 0.91 1 *oo - 4.61 5.69 2-73 I I 10.58 15 04 1.00 39.65 Cuddes don, 4,045. 1.3 2.83 6.16 7.35 1.05 1.33 - 2.13 5.03 0.06 - 1.54 11-72 1-38 21*81 - 454. 1 2,528. 4,360. 4,160. 3.3 3.3 10.78 I- -- 1.1 2.2 9.5 8.12 0.85 0.7 -- - 1.81 3.91 3.90 - 1-78 14.50 0.70 - Constituents E s t i - mated. Chlorine ... ... Sulphuric acid (SO,' Carbon dioxide (GO,: I 43.40 21.36 16-78 60.5 1 173.6 22.8 i 201.2 17*00 126.68 25-41 67-20 34.88 19.70 5.60 28.01 11 *08 104.64 - 86-16 56.64 5 *60 4.1 70.30 4.0 38.26 6-39 13.42 1.96 6.73 22-80 19.39 - I 75-41 12-87 1.96 12.32 5.5 6.1 2.1 2 *1 -- - 101.0 187.3 5.4.0.34 - - 10-7 2.1 Lime (CaO) ... Magnesia (MgO) . . . Soda (Na,O) . . . 20.4 6-0 1.19 - 286-0 323-9 18.0 - - 11-42 28.0 1-19 -- 5-1 8 1.61 - - 5.44 5.86 11.90 - 3.38 9.25 ? --- 0.98 27.16 ? - 4-31 2.14 0.70 - 1-19 0.90 74-40 0.91 71.51 37.91 34.14 - 1-88 2.12 0.91 - Silica' (Sid,) [and (Fe,O,)] . . . ... Calculated as Con- stitwnts in Com- banation. Sodium chloride . . . Sodium sulphate ... Sodium carbonate Magnesium sulphate Magnesium car- bonate ... ... Calcium sulphato . . , Calcium carbonate Silica (and Fe,O,) 7.41 11.18 29.65 - 3.95 5.89 13.70 4-49 7 -70 0.70 - Totals ... 306.84 35-83 49.99 I 36-43 52-57 139.56 - 148.47 192.13 ._TABLE VII1.-GREAT OOLITE AND OXFORD CLAY.Molecular Ratios of Chief Constituents in Grains per Gallon divided by the Molecular Weights. Woodhani, near Brill, 2,360. --- 1.272 3 a458 Locality : No : Chlorine (Cl,) . . . ... ... ... I 2.445 ' 0,0577 Sulphuric acid (SO,) . . . ... ... 1 2.515 0.8775 Carbonic acid (CO,) ... ... ... 0.280 1 0.0909 Lime (CaO) ... ... ' 0.364 1 0.6832 Magnesia (MgO j ' ... ... ... 0.150 1 0.1597 ... I 4.726 1 0,2164 I Soda* (Na,O) ... ... ... ~ Oxford, i Strattori I Audley, 2,628. 1 3,735. I Chwell, Hicester, 4,360. Locality : No : 0,0155 0.0275 0.2128 0.1450 0.0212 0.0958 ~.______ Rourton, Swindon, 3,624. 4,199. ---- Langford , Ricester, 4,160. Chlorine (Cl,) ... ... ... ... Sulphuric acid ( SOij ' . . . ... ... ... Carbonic aoid (GO,) . . . ... ... ... Magnesia (MgO) . . .... ... ... ... ... ... ... ... Lime (CaO) . . . Soda* (Na,O) ... ... ... ... ... ... 0.0465 0.0412 0.2540 0.0925 0.0402 0*2000 0 6112 0.2670 0.3813 0.0212 0.0223 1.2000 Ambrosden, Ricester, 3,027. 0.0634 0.0787 0.2973 0,0175 0.0 0.4380 TABLE VIII.-CORALLIAN AND KIMMERIDGE BEDS. Stratton Audley , 3,904. 0.0338 0.0415 0.2800 0.0770 0.0535 0-2255 Marsh Gibbon, 4,151. -- 0-0764 0.0756 0.3184 0.0413 0.0182 0.41 09 2.217 2.212 Molecular .Ratios of Chief Constitzceizts in Grains per Gallon divided by the Molecular Weights. +4 u3 0.3662 0.0456 0.4231 0.0250 0.0252 0.7847 Raldon, 4,112. 0.0394 0.1406 0.1504 0.2282 0.0227 0.0795 Cuddesdon, 4,045. - 0.0260 0.0506 0.2000 0.1674 0.0262 0- 051 5 - __ Brill, 3,814. -- 0.2394 1.5830 0,5775 1.200 0.872 0.318 9 SEA- RATER. 19.270 1.975 0.085 0.738 3.825 16.740 * Traces of potash are included.The figures in italics are calculated by difference.36 THE ANALYST. From w e b in the oolites, however, harder waters are obtained, especially from the deeper sinkings, of which a few examples are given in the same table. S E A LEVEL Taters below Ozford CEay.-The Great Oolite beds, with Forest Marble and Corn- brash, pass in this district below the Oxford Clay, dipping gradually in a south-eastTHE ANALYST. 37 or southerly direction, and when the waters which they contain are tapped by boring, the characters of the supplies are found to alter in a remarkable manner. As no downward percolation is possible through the superinoumbent clay, the waters must flow along the lines of the porous beds often for long distances, and, gathering more and more the soluble constituents, become increasingly saline in character. The waters in Table II., from Witney, Oxford City, and Inglesham, are typical examples of such salt waters, ell being probably derived from the Forest Marble beds.The amount of alkaline salts, indeed, is so great that the waters are quite useless for domestic or industrial purposes. A boring made in 1832 for a brewery at St. Clement’s, Oxford, and cwried to a depth of 420 feet, yielded a highly saline water, of which the chief constituents were found by the late Mr. W. F. Donkin to be 748 grains of common salt and 357 grains of sodium sulphate in the gallon, the total dissolved solids being 1,277 grains. (See Woodward, “Jurassic Rocks of Britain,” vol.iv., p. 514.) An interesting boring through the entire series of oolttes at Swindon to a depth of 736 feet is also described by Mr. Woodward, and an analysis of the water given. The amount of alkaline chlorides was at first 1,841 grains per gallon, with 279 grains of calcium and magnesium chlorides, the total solids being 2,131 grains per gallon. An analysis made in 1902 showed a diminution of chlorides to 1,673 grains. The bore-hole now being blocked in its lower part, the salt water cannot be obtained; but the sample inTable V. (4,199) was obtained from the upper part of the boring last year. Mr. Churchward, the engineer to the Great Western Railway, informs me that the salinity gradually increases beneath the clay. H e says: “ A year or two since 1 tested by borings the water from Swindon to Kemble (where the clay ends), and found the chlorine diminish all the way until it reached about 1.6 a mile this side of Kemble Station.” A gradual change of this character can be distinctly traced in two series of wells in the Bicester district. The Middleton water (2,392, Table I.) is an ordinary limestone water, while the waters from Gowell (4,360, Table I.), Langford (4,160, Table II,), and Ambrosden (3,027)) show a gradual transition to alkaline waters, con- taining only small amounts of calcium salts.These wells lie nearly in a straight line five miles in length. Another line of wells is from Fringford (3,076, Table I.), through Stratton Audley (3,904, Tables 11. and VII.), to Marsh Gibbon (4,151), in which the successive changes are similar, the distance being about four miles.It is probable the Grendon Underwood water (3,517) is a continuation of this series. The waters at Ambrosden and Marsh Gibbon are interesting from the fact that they contain some peaty matter in solution, which imparts to them a brownish tinge. The waters are soft and alkaline, and are in use for domestic purposes; one well, indeed, supplies a large part of the village with water conveyed by pipes to the public taps. The geological map of this district shows that the oolite beds, after passing below fhe clay, rise again to the surface, forming several patches or inliers of limestone, upon which the above-mentioned villages, with Oddington and Merton, are situated. This will be clear from the section and sketch-map.This is from the Corallian beds. See Table VII. for relative quantities of sodium salts.38 THE ANALYST. It should be remarked that saline waters from under clay normally contain free ammonia, with considerable quantities of organic matter, but only small proportions of nitrates, thus differing widely in type from ordinary limestone supplies. The presence of the peaty matter in the waters described has been difficult to explain ; but as the brown organic substance is precipitated when the waters are neutralized with acid, it clearly comes from the solvent action of the sodium carbonate upon some constituent in the oolitic beds. The recent boring at Gowell, near Bicester, affords information which may explain this peculiarity. Down to 90 feet the beds consisted of various rocky, shaly beds, with no water ; then water was reached in sandy deposits, and at 108 feet a layer of " peat " was met with in sand, from which the bulk of the water came.A specimen of this deposit proved to be a mixture of brown vegetable matter and sand, partly soluble in weak sodium carbonate, imparting to it a brownish tint. Similar peaty deposits may occur at. Ambrosden and Marsh Gibbon, and their presence would explain the origin of these brown waters. Oxford Clay.-Owing to their generally impervious character these beds do not yield water in any quantity; occasionally wells are dug, and the composition of the waters obtained is shown by some examples in Table 111. Many have been taken from trial wells sunk in attempting to provide water for public supply, but the exces- sive quantities of calcium and magnesium compounds and especially their sulphates render the waters unsuitable for domestic purposes.The presence of saline ammonia and somewhat large proportions of organic matters are worthy of note ; the nitrates are generally small in amount. Corallian Oolite.-The Corallian oolites rest on Oxford Clay, and are composed partly of calcareous grit and partly of coral rag limestone with occasional clay beds. Although much smaller in extent than the great oolite series and of no great thick- ness, they are important sources of supply for many villages in Oxfordshire and Berks, and numerous wells have been sunk in these deposits. Generally the waters obtained are rather hard, as will be seen on reference to Table IV., and the organic impurities are small; but the nitrates, as might be expected, are very variable, according to the state of the surroundings of the wells.Waters below Kimmeridge Clay.-When the Corallian beds pass in their turn below the overlying Kimmeridge Clays and can only be reached by borings, the characters of the waters found are widely different from those previously described. The increase of alkaline salts is very noticeable, and the waters are frequently soft and alkaline. The Burcote water (2,339, Table V.) is a typical example of the change, while the Bourton (3,624) and Swindon (4,199) waters may be compared with the Faringdon (2,236, Table IV.) from the same beds a short distance away. In the case of the Baldon (4,112) and Cuddesdon waters the change of type is less complete, but the proportion of alkaline salts has increased in both.Kimmeridge Clay. -Attempts are made occasionally to procure water from this clay, but with little success, as the waters are for the most part extremely hard, owing to the large amounts of calcium and magnesium salts. Some examples are described in Table VI., and the detailed analysis of the Brill water (3,814, Table VII.) shows a, remarkable excess of magnesium sulphate. It is only to be expected that the more saline waters would decrease in salinityTHE ANALYST, 39 after a time, and, indeed, this frequently happens to a greater or less degree, according to the quantity of water drawn. The Buckingham water, after fourteen days’ con- tinuous pumping, was very different in character from that first obtained from the boring : since 1901, however, it has remained fairly constant in composition.The Longford water altered considerably in five years, but the composition of the water a t Marsh Gibbon has not varied to any noticeable extent for nearly twenty years. The study of oolitic waters leads to the general conclusion that the uncovered beds of limestone yield calcareous waters of a hard character, while the deep beds, and especially the beds covered by clay, yield saline or alkaline supplies. In earlier papers (ANALYST, 1901, 1902) it has been shown that alkaline waters are similarly found in the Chalk below London Clay and in the Lower Greensand or Portland, beneath Gault Clay. Further instances may be adduced of alkaline supplies being obtained under similar conditions from beneath the Wealden Clay and also Upper Lias Clay.Thus we find in geological deposits of various ages and extending over an enormous period of time a general similazity in respect of the alkdine constituents of waters whenever the strata Eire covered by impervious deposits. Some general cause must be looked for to explain this general identity ; and the evidence clearly justifies the conclusion that the alkalies are normal constituents of the strata, from which the waters are obtained, and are not derived from any external source, which hitherto has been the general assumption. Among engineers the opinion prevails that chalk waters in the London basin derive their salt from the infiltration of sea-water, although this would not explain the alkaline sulphates and carbonates also present in quantity.If chalk under London and Essex communicates to any appreciable extent with the sea, the waters would become increasingly saline as pumping continues, but the constancy of com- position of the Trafalgar Square well, and of many others, is evidence to the con- trary. Further, the gradual fall of level of the wells shows there is no ready access for sea-water. I t must not be forgotten also that chalk water at Windsor contains very moderate quantities of alkali, while a few miles further, at Wokingham and other localities, large amounts are found. The water-levels of inland wells lend no support to the view mentioned above. In the case of the overflowing wells near Bicester the surface is 210 feet above ordnance datum, and at Swindon the water-level is 300 feet above sea-level.All the cases under discussion hang together, and my engineering friends will need to revise their opinion in respect of the alkaline chalk water under London. Among geologists the possibility of a connection between salt deposits in the Trias and the saline oolite waters is the hypothesis most in favour. The late Sir Joseph Prestwich, in his paper on the saline water from the deep well at St. Clement’s, Oxford, inclined to this view, suggesting the possible thinning out of the Lias near Oxford. But the borings at Swindon and Inglesham have since been made, and as the Lias presumably underlies the oolite in both localities, it seems hardly possible that any communication can exist with the Trias.Further, the Trias salt- beds would furnish sodium chloride, but neither the sodium sulphate nor sodium carbonate are characteristic of oolite supplies. The chemical argument appears absolutely destructive of the sea-water (or salt-40 THE ANALYST. beds) hypdhesis if the figures in Table VTII. are critically examined. The molecular ratios there calculated afford a ready means of comparing the quantities of each constituent of the oolite waters and sea-water. The chlorine in sea-water is sufficient to combine with all the alkali and part of the magnesia; the sulphuric acid is a tenth of the chlorine, and only suffices for part of the rnagneeia and a small quantity of lime. I n saline well-waters the proportion of soda is not only in excess of the chlorine, but sometimes greater than the sulphuric acid in addition, and a portion is found as carbonate.This excess of soda cannot be derived from sea-water, but must be a constituent of the rocks in which the waters are found. A suggestion has often been made that alkaline silicates, being decomposed by carbonic acid, may furnish the alkaline carbonates in some waters; but there is no evidence of any weight that such an action takes place either in the days or lime- stones under consideration. I venture to propose an entirely different hypothesis, and to suggest that the alkaline oarbonates owe their origin to the decay of organic matter originally deposited in and with the rock material, part of which still remains, and from which the products of decomposition have not been removed by the circulation of underground waters.I t is preciselyin situations where there is little or no move- ment possible that saline waters are met with. The abundance of fossil remains indicates a profusion of animal and vegetable life at the time of the formation of these deposits, and in them lignite, peat, and even animal matters, more or less fossilized, are still left in many places. The ashes of plants and animals are rich in alkaline salts, carbonates, sulphates, and phosphates, and it is reasonable to suppose that when the organic matters originally decayed, the products of decomposition not lost as gases would remain in part, at least, among the materials in which they were embedded.Further, unless washed away later by subsequent exposure of the beds and percolation of rain-water, such remains would continue even to the present time. I t seems probable that the ammonia normally present in saline waters, together with the somewhat larger quantities of organic matter, may have a common origin with the alkaline constituents. This part of the discussion must, however, be reserved for further experiment and investigation. I wish to thank Mr. A. E. Ellis for his help in the analyses of the mineral constituents of some of these waters. DISCUSSION. The CHAIRMAN (Mr. Sidney Harvey) said that in his own district the waters derived from the lower tertiary formations contained amounts of free ammonia which were relatively very large. Such waters had, indeed, occasionally been condemned a8 containing organic impurity, though the albuminoid ammonia and oxidizable organic matter were small in quantity.The figures for chlorine were generally high, and sodium carbonate was very frequently present. Mr. ALLEN said that in his experience calcium carbonate was soluble in water to the extent of about 1.3 grains per gallon, and magnesium carbonate to a, greater extent, so that the alkalinity of the residue would seem to be scarcely sufficientTHE ANALYST. 41 evidence in itself to enable one to regard it as fully demonstrated that what was present-especially when the quantity was small-w-as really sodium carbonate. Mr. W. T. BURUESS said that the change which had taken place ili the water from Langford after an interval of five years was rather curious.It did not seem to have been due to the washing out of the more impure water that might have got into the well at first, since, although the total solids had decreased, the quantity of chlorine in the later sample was greater than that in the earlier sample. A very remarkable change, too, was that which had taken place in the m e of the Bucking- ham well, in which the total solids, originally 60 grains per gallon, were a week later 68.7, but after another week had decreased to 30 grains per gallon. The water from Inglesham, again, was apparently entirely different from any of the others. From the proportion which the chlorine bore to the total solids, the latter must consist of little else but pure sodium chloride.It seemed a pity that the figures of water analyses were so often confined chiefly to those relating to the changes undergone by organic matter, for the possession of additional data, such as those which Mr. Fisher had given, and their study in relation to the geological formations in which the wells or springs were situated, would in many casefi afford valuable information that might not be otherwise obtainable. Mr. HEHNER said, while he was much inclined to accept Mr. Fisher’s suggestion that these alkaline salts, and especially the carbonates, were derived from organic remains, he could not help feeling that that theory-as Mr. Fisher had, in fact, mentioned-was beset by It was customary to look upon the nitrates in water from deep chalk wells as being obviously derived from the nitrogen of the animals that deposited the chalk.I t was no doubt easily imaginable that the ammonia which was found in such waters represented non-nitrified nitrogen, though it was often suggested the ammonia was the result of reduction of nitrates- not, however (as the old theory had it), by the action of iron pipes, but more probably by the action of micro-organisms. The chief difficulty appeared to be the fact that many strata which abounded in organically-derived substances did not yield alkaline waters. Kimmeridge Clay, for instance, was full of fossils belonging to comparatively recent periods, and yet water from the Kimmeridge Clay was never alkaline, but contained calcium sulphate. Of course, it might be said calcium sulphate pre- dominated in that formation, and whatever sodium carbonate might be formed would be precipitated as calcium carbonate, and overwhelmed and eliminated by the calcium sulphate.I t was difficult to see why, if that were so in the case oE the Kimmeridge Clay, it should be otherwise in the oolite and limestone beds. The presence of sodium salts could not well be due to sea-water in the oolitio beds of the South Midlands. On the other hand, in the South of England alkaline waters, undoubtedly from the chalk, were frequently met with when the chalk was overlapped by clay, and where the sea was only a few miles off, some, at any rate, of the salinity was due to sea-water. Mr. D. A. SUTHERLAND inquired whether the wells which Mr. Fisher referred to were iron cased, and, if so, whether the lining w a ~ continued through all the strata to the bottom ; and also whether any investigation had been made as to the presence of iodides or bromides, etc., in those waters in which the quantity of chlorides W ~ S great many difficulties.42 TEE ANALYST.high. It was interesting to note that on distilling Kimmeridge bituminous clay, mineral oil was yielded in copsiderable quantities, and the richness of that formation in nitrogenous matters was shown by the fact that in mme cmes it was capable of yielding as much as 30 pounds of sulphclte of ammonia, per ton when distilled in an ordinary shale retort. Mr. KITTO inquired whether, in advising that the peaty water from the ‘‘ boiling well” at Ambrosden might be used for drinking purposes, Mr.Fisher had considered it permissible to use the water as it came to the surface, or whether he had required the water to be pumped from below the peaty bed, when its condition would presumably be much better. Mr. SUTHERLAND said that the question of the water passing through a peaty bed had led to his inquiry as to the lining of the wells. It would be interesting to know if any examination had been made for the presence of sphagnum cr other characteristic matter. Mr. CHAPMAN thought that there could be little doubt as to the correctness of Mr. Fisher’s earlier explanation in regard to the occurrence of sodium carbonate in these waters from the chalk underlying the clay, and the explanation which he now suggested of the presence of appreciable traces of free ammonia in such waters certainly seemed probable. Free ammonia occurred, as was well known, in consider- able quantities in nearly all waters derived from any form of chalk bed underlying clay, and in London well-waters it sometimes occurred to the extent of very nearly $c grain per gallon.He (Mr. Chapman) had thought it not impossible that this formation of free ammonia might be explained by the increased activity of micro- organisms owing to the slight alkalinity of the water ; and it might be noted thti,t, as a general rule, the waters referred to by Mr. Fisher, which came from below the clay, contained less nitrates and more ammonia than those from the clay itself, which seemed to favour the denitrification theory. Of course, many of the organisms existing in water were oapable of reducing nitric acid and nitrous acid, and it seemed quite conceivable that in the case of theae waters such organisms might have been actively at work.He was iaterested in Mr. Fisher’s remark that the peaty water referred to was nearly sterile, because during the last few months he had had occasion to examine bacteriologically two or three peaty waters, and had found it extremely difficult to obtain the ordinary growths from such waters. Colonies formed on the ordinary gelatine medium, but they took from twenty-four to thirty-six hours longer to develop than usual, and were even then comparatively small and attenuated. It seemed as though some of the peaty or humus constituents exercised a paralyeing effect on the bacteria. The fact that, in the case of both the Oxford and the Kimmeridge Clays, the waters derived from the clay beds were altogether different from those derived from the underlying oolites seemed completely opposed to one of the alternative theories that had been suggested to account for the presence of sodium carbonate, free ammonia, and sodium sulphate-namely, that these were really the constituents of tertiary waters which had penetrated through the fissured chalk. From Table V.it would seem that, in the waters from below the Kimmeridge Clay, just as in those from below the London Clay, there was a fairly constant connection between the presence of alkaline carbonate and the presence of free ammonia.THE ANALYST. 43 Dr. DYER said that in reference to the organic remains present in deep deposits it might be interesting to mention that some few years previously the late Sir Henry Gilbert had made nitrogen determinations in a number of specimens of deep clay deposits taken from various places, which had been supplied to him partly through the Geological Survey, and on an average it had been found that these deep clay deposit3 contained as much aa from 0-03 to 0.04 per cent.of nitrogen aa the survival of the organic remains which must have been originally deposited with them. The quantity of nitrogen seemed remarkably constant, and in the deep clay subsoils at Rothamated as far down as 9 or 10 feet, and beyond the influence of surface vege- tation, the proportion of nitrogen was about the same-namely, 0.04 per cent. Taking into account, therefore, the large surface of clay with which a water travelling underground must come into contact, there must be opportunities for its taking up nitrogen in some form or other.Mr. FISHER, in reply, said that he had not been able to make any detailed examination of the peaty material from the Ambrosden well, as the quantity at his disposal was only very small, but he hoped to be able to obtain some more of it, With regard to the important point raised by Mr. Hehner as to the absence of alkaline carbonate in waters from the clay itself, even when the latter-as was the case in the Kimmeridge beds-abounded in organic remaina, he expected to find, when he should be able to examine that part of the subject more minutely, that these clays did contain carbonates of the alkalies; but it must be borne in mind that the water in any clay bed was necessarily in contact with a comparatively limited quantity of material, the reason why the waters from porous beds showed alkaline carbonates, while those from clay beds did not, being that the water could move in the porous beds along the lines of stratification or through the material itself, while the clay was so impervious that the water could not travel any great distance through it.He had noticed sometimes, in water from wells in the clay, that at first the quantities of dissolved solids were so large as to render ihe water almost unusable, but that if pumping were continued for some time water was obtained containing a good deal less dissolved matter. With regard to the sodium carbonate question, he thought there could be no doubt that sodium carbonate did actually exist in the chalk, and its much greater solubility would account for its preponderance over calcium and mag- neEium carbonates in the water.It was certainly the case that, on evaporating to dryness a water containing magnesium carbonate, some of this was decomposed, leaving a feebly alkaline residue of magnesia and a basic carbonate, but in really alkaline waters the alkalinity of the residue was so marked that there could be no question as to its origin. He could only explain the change in the character of the Langford water by the supposition that during the interval of five years-probably owing to the larger flow of water-there was less soluble matter in the beds than there used to be.He had, however, had occasion qnite recently to examine a further sample of it, which showed the water to be substantially the same in character as the last sample referred to in Table I. The Swindon well, in particular, he believed to have been very carefully made, and it was probably lined, though he did not actually know this to be the case. The last analysis in Table V. The Buckingham water was certainly a remarkable one. In some cases the wells were lined, in others not.44 THE ANALYST. represented the water at present obtainable from the Swindon well. He had not looked for either iodine or bromine in any of the waters, having been obliged some- what to limit the scope of the investigation. The question of the peaty water had been puzzling him for several years, his attention having been first drawn to it by Sir Henry Acland. On investigating the matter at the time he had been thoroughly convinced that there was no infiltration from the outside, He had had one of the we[ls emptied to the bottom and the bore-hole plugged, and it was found that some of the water taken as it came out of the bore-hole was of exaotly the same character &S that which overflowed from the top. Even, however, if the walls of the well had been defective, it would be very difficult for any impurity to make its way in against the pressure from the inside. This water gave bacteriological results similar to those described by Mr. Chapman. Practically no organisms developed for three days, and after that the colonies were very few in number and doubtful in character. With regard to the ammonia, it seemed to be of little moment whether this had once been in the form of nitrates, or whether it had always been ammonia. The main point wag that, practically speaking, all the products of decomposition of organic matter were present. Of course, the chloride of sodium might be a residuum of sea-water if no washing out had taken pIace, but he thought that that was only part of the story. The presence of the sodium carbonate and also of phosphates were the points that needed explanation. He had been much interested in Dr. Dyer’s mention of Sir Henry Gilbert’s work, and hoped himself to have some opportunity of trying to add a little to existing knowledge in regard to the materials obtained from clays.