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In the gravel of the tops, slopes, and valleys are numerous shallow wells, rarely exceeding 30 feet in depth, the water being held up by the solid gneiss below, which under the ridges forms solid walls separating the basins of adjacent valleys. Each of the above-named valleys has its surface stream, which begins gradually in the gravel of the plateau, and perfectly clear when I saw them after melting snow, February 22, 1888. Along the valley lines, which fall about 100 feet per mile, the rock is also disintegrated, and this forms a secondary store, from which the perennial flow of the streams is partly maintained. For a well sunk near the bottom of the valley falling to Perelle Bay I found an area of 2 square miles on which a percolation of 3 inches per annum would give a supply of 238,000 g. p. d. (24 hours). The water level in a shallow well at the site was about 56.57 feet above

mean tide level, and the surface 60 feet. The range of the tide is 32 feet, so that the W. L. in the well was 40 feet above H. W. M., and the distance from the shore 1,130 yards. As a second well I recommended the valley below Kingsmill. Both these wells have been since carried out, and are now supplying the island.

FRESHWATER.

On March 28, 1888, after a survey made March 22-24, I reported on the best means of supplying Freshwater district.

For 1 mile east and 3 west of Freshwater the south coast is formed of chalk cliffs, reaching 700 feet + O. D., and dipping north at angles of 70° and 80°, the whole chalk being under mile wide. On the north this chalk is bounded by a vertical wall of clay rising 100 to 200 feet O. D., and consisting of plastic clay 84 feet

and London clay 200 feet, in all 284 feet, which causes all the chalk water to flow south from the wall of clay (where it may attain some 25 feet + O. D.) to the sea.

This is true except of Freshwater Gap, which is cut right down to sea level. Here an ebbing and flowing spring breaks out on the east side and rises some 4 inches with the tide. At the utmost this spring could not flow more than 35,000 g. p. d. fresh water.

Eastward of Compton Bay the chalk water system is held between two walls of clay, the plastic and the gault clay, which rises at a steep angle to a greater height than the plastic clay, and cuts off its escape towards the south. The water in the chalk therefore, rises so rapidly eastwards, that it throws out a spring at Chessel over the barrier wall of the plastic clay on the north at 240 feet. D.

I visited this spring on March 23, 1888, and estimated the area of supply at square mile (which at 6 inches. percolation gives the mean flow at 119,000 g. p. d.), and recommended that the water might be taken by a well in the chalk above the spring or from the stream at the surface.

The vertical wall of plastic and London clays also prevents any water from the Bagshot sands from flowing south, consequently the various vertical sandbeds of this group throw out small springs in each valley they cross, draining north. The Bagshots consist of sands, marls, and clays, and are divided into lower, middle, and upper, the lower 665 feet thick at Alum Bay, one sand bed being 192 feet thick. To the top of the lower Bagshots from the chalk is 948 feet 5 inches thick. The middle Bagshot, or Bracklesham and Barton clays, are 411 feet thick, the top being 1,359 feet 5 inches above the chalk.

The upper Bagshot sand is 122 feet 4 inches thick at

Alum Bay. Its top crosses the bed of the Yar just above the tidal sluice. Immediately south of this point it delivers its waters in the springs at Afton House. I therefore suggested a trial well about 120 feet deep to the base of the upper Bagshot sands, their beds showing in descending order the following series, measured in feet:

[blocks in formation]

A well was sunk, without my knowledge, 13 feet, and bored 4 feet in the wrong place, where no Bagshot was present, the parties being guided by the Geological Survey Map, on which the Bagshots for nearly two miles across the basin of the Yar are carried too far north. The well went through gravel into the Lower Headon beds. The Bagshots in the basin of the Yar give 368 acres in area, which at 3 inches percolation gives 68,430 g. p. d., and the demands for Freshwater had been enlarged to 100,000 g. p. d. On October 9, 1890, after visiting Freshwater again, I suggested that a shaft of 20 feet should be sunk in the chalk just behind the ebbing and flowing spring at Freshwater Gate and pumped for 10 hours with a pump capable of throwing 100,000 gallons in the time, and that samples should be taken at the commencement and termination of pumping. This was done, and Freshwater has since been supplied from that spring. The Chessel springs

were gauged October 7, 1890, at 121,000 g. p. d., on which occasion Mr. Way, the tenant, told me that he had never known the springs lower.

BURIAL GROUNDS.

Under Section 7 (1) (c) of the Parish Councils Act, 1894, in every rural parish the parish meeting has the power of adopting the Burials Act 1852 to 1885; and by Section 12 a Parish Council may, with the consent of the County Council and the Local Government Board borrow money for the purposes of any of the adoptive Acts. The Local Government Board Report, 1895-96, states (p. xl.) that the Board consented during the year to the borrowing by six Parish Councils of sums, the whole of which was required for the provision of burial accommodation.

To secure the water supply from pollution where such supply is drawn from wells, the decision of the Local Government Board in the case of Sutton, Surrey, forms a useful precedent. In 1886 the Sutton Local Board applied for sanction to a loan to enable them to make a cemetery on a ridge of the chalk just north of Banstead Downs, the site in question being also situated upon a water-ridge from whence the water in the chalk flows towards Carshalton springs and Sutton Waterworks on the east side, and towards Cheam on the west. After an inquiry held at Sutton, the Local Government Board disallowed the site and the cemetery has since been made on the London clay.

In November, 1888, it was proposed to extend the churchyard of St. Nicholas, Barton-in-the-Clay, Beds, in a direction north of the old burial ground. This was

opposed by Francis Benthall, Esq., owner of some houses in Barton village, a short distance N.W. of the proposed site, which was on a ridge of "chalk marl," sloping east and west, and ultimately draining north on both sides. The direction of the flow of the subterranean water was proved to be N.W. from the site, or right across these wells; but it was also proved that on the east side of the ridge the subterranean flow is N.E., and that if the burial ground were enlarged towards the east it would not injure any existing well, as there are no houses on that side. The report was adopted by the Burial Board, and the easterly extension was afterwards carried out.

Early in 1890 the Right Honourable George Cubitt, M.P., now Lord Ashcombe, owner of a house and some land adjoining the burial ground of Churt, Surrey, on the N.E., offered to demolish the house, and add the land to the burial ground, whereupon a gentleman objected on the ground that a well at a house belonging to him adjoining the churchyard on the N.W. would be polluted, and it was also objected that the vicarage well to the N.E. might also be polluted. The village of Churt stands upon a short spur of the Sandgate beds, nowhere exceeding 40 feet thick under the village, into which several shallow wells had been sunk, the water in them being held up by the argillaceous base of the Sandgate beds. The bottoms of these wells range from 318 feet to 332 feet+O. D. There are also three deep wells sunk through this base to the springs of the Hythe beds, their bottoms ranging from 280 feet to 282 feet + O. D. Both water systems, Sandgate and Hythe, show a distinct water-ridge running north through Churt, between Frensham Great and Little Ponds, as far as Frensham village. The steepest line of fall on the water surface was north-east from Kara's well to a point a few yards

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