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hood of Folkingham, a tract of clay land was, several years ago, drained with tiles laid 3 ft. 6 in. deep, and the surface, which was in broad bands with high ridges, was levelled. After a short period, however, the texture of the clay became so solid that the surface-water could not get down to the drains, and it became necessary to alter the method. On the same lands, drains now made 18 to 24 in. deep are found entirely successful. In the neighbourhood of Newcastle-on Tyne, some clay lands have been drained by drains laid 2 ft. deep and 20 ft. apart, with highly satisfactory results. In various parts of Scotland, the subsoils of retentive clay have been more completely drained by drains 24 ft. deep and 18 ft. apart, than by 4-ft. drains laid 36 ft. apart. In the counties of Worcester, Hereford, &c., the best drains in the clays are those laid from 2 to 3 ft. in depth; those made 4 and 5 ft. deep being found far less effective. Mr. Tebbet of Mansfield, near Nottingham, a practical authority of éminence, states that the best way he has adopted on strong clay lands is putting the drains 14 ft. apart and 2 ft. deep; while he finds other clays that will draw at 18 to 24 ft. apart, and 2 to 3 ft. in depth for the drains.

122. A kind of average scale for the dimensions and distances of drains may be drawn from the experience we have hitherto had in the draining of land. Classifying the varieties of soils into three divisions, as Compact, Medium, and Porous, each of which may be subdivided into several degrees of retentiveness or porosity, the distance of the drains apart may be graduated from 15 to 60 ft., and their depth ranging from 2 ft. 6 in. to 4 ft. 6 in., as follows:

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123. The cost of draining is necessarily a theme of deep consideration in the execution of any plan which appears likely to be most successful. The following records state the size and distance of the drains, the nature of the soil, and the total expense per acre :

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The first eight of these cases are quoted from Mr. Smith's (of Deanston) Pamphlet. They are instances of hard subsoils, with tiles and soles.

124. Nos. 9 to 16 are cited by Mr. Josiah Parkes, in the 6th vol. of the "Journal of the Royal Agricultural Society," the drain-pipes being supposed to be made upon the estate, and costing 6s. per thousand.

125. The remaining cases are also given by Mr. Parkes, viz., in the "Gardener's Chronicle," the tiles being made upon the estate, and drawn by the tenants.

126. The several items of cost of draining a rectangular field of 20 acres, with drains 3 ft. deep, and 22 ft. apart, may be averaged thus:

Main drain, 60 rods, at 8d. per rod for cut

ting and filling

Drain pipes, 990, at 40s. per thousand

£ s. d.

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Minor drains, 22611⁄2 rods, at 41d. per rod. 42 8
Drain pipes, 37,320, at 30s. per thousand. 55 19

Equals 51. 2s. 6d.

0

7

£102 9 81

per acre.

The main drains are supposed to be 3 ft. 6 in. deep, 20 in. wide at top, and 4 in. in the bed, with pipes

4 in. in diameter. The minor drains are supposed to be 3 ft. deep, 15 in. wide at top, and 3 in. in the bed, with pipes 3 in. in diameter.

127. The several items of cost of draining a similar rectangular field of similar soil, and prices for cutting and filling in proportion to the sectional area of the drains; the field being, as before, 20 acres in extent, with drains 4 ft. deep, and 45 ft. apart, may be estimated thus:

Main drain, 60 rods, at 1s. 2d. per rod for

cutting and filling

Drain pipes, 990, at 40s. per thousand

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£79 29

Minor drains, 1109 rods, at 10d. per rod for

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Drain pipes, 18,300, at 30s. per thousand

Equals 31. 19s. 1d. per acre.

The main drains are supposed to be 5 ft. deep, 24 in. wide at top, and 4 in. at bed, with pipes 4 in. in diameter. The minor drains are supposed to be 4 ft. 6 in. deep, 21 in. wide at top, and 3 in. in the bed, with pipes 3 in. in diameter.

128. Mr. Smith gives estimates for drains constructed with reference to the nature of the soil, which may be arranged thus:

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Mr. Smith also mentions a district of 10,000 acres of stiff compact clay soil in Scotland, which has been satisfactorily drained with drains 2 ft. deep, and laid 20 ft. apart.

129. Stones, as used for the filling of drains, are of two kinds, viz., the pebbly, or round stones, obtained from the sea-coast, or channels of inland streams, and the fragments produced by breaking up stratified or other rocks, and procured from the quarry. Of these, the former are much superior as the materials for drains, as they preserve the interstitial channels more permanently than the angular scraps from the quarry, the several projections of which are liable both to block up the spaces, and to be broken off by ramming, and thus interfere very mischievously with the passages for the water. As to the size of the stones, the standard commonly prescribed, namely, "the size of a goose's egg," is as good as any. At any rate, none should exceed 4 in. in diameter, or be less than 2 in. In all cases the stones should be assorted according to size, and used separately. Carelessness, in this respect, often leads to the complete choking of the drain, by the smaller stones filling up the spaces between the larger ones, and forming an impermeable dam across the drain.

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