Читать книгу The Palace and Park - Edward Winslow Forbes - Страница 56

The high towers, of which there are two, one at each end of the building, have been erected for the purpose of raising the tanks from which the high jets of the great fountains in the lower basins are played, and are, with the exception of the tank and stays, constructed of cast iron.

The foundation upon which this enormous mass of material rests, is necessarily very strong, and consists, in the first place, of a ring of concrete, sixty feet in external diameter, and three feet deep; upon this is built a circular wall of brick-work, laid in cement, fifty-six feet in diameter, and eighteen feet deep. This forms the bed on which rests the base pieces of the columns.

The columns, 1 foot in diameter, and 24 in number, are placed in pairs, 4 feet apart, and are connected together by solid vertical girders or filling-in frames, each pair thus forming one continuous broad column, extending from the base to the bottom of the tank by which the tower is surmounted; the whole rising to a height of 202 feet. The space between each pair of columns (8 feet) is filled in with glazed sashes and face-work, corresponding with those in the building, and completing the shell of the tower. Behind these sashes, and spanning these spaces, extending from floor to floor, are series of round wrought-iron diagonal bracing, continued from the bottom to the top of the tower; and, under each of the ten landing-floors, is a strong horizontal bracing-plate, termed a diaphragm, forming, with the diagonal bracing above referred to, a system of vertical and horizontal trussing.

Up the centre of each tower is carried a perpendicular brick shaft (the internal diameter of which is 7 ft. 9 in.), resting upon a separate foundation, and serving the double purpose of carrying off the smoke from the heating apparatus, from the boilers connected with the Machinery Department, the upper engine-house, and kitchen, and forming the core or spiral staircase by which the various floors, and gallery at the top of the tower, are reached. These floors arise at intervals of twenty feet from the level of the floor of the main building. The tank noticed above is of boiler-plate, and is formed of an inner and outer wall, the former of which encircles the chimney-shaft; the bottom, which is dome-shaped, is carried upon wrought-iron girders radiating from the chimney, and is secured to the tops of the external columns. This description will be more readily understood when the depths of the tank at its outer and inner walls are given. The former, or that resting upon the external columns, being 38 feet, while the latter, next the chimney-shaft, is about 26 feet. These tanks are calculated to hold, when filled, a body of water of the enormous weight of 1,576 tons, or a bulk of 57,228 cubic feet, equal to 357,675 gallons.

The supply is forced from the upper reservoir by the same engines that raise the water to the lower water-tanks and the building; and the same pipes form also the means of conveying the water to the fountains. They are arranged within the outer columns, forming an interior circle, apparently of columns, but rendering in reality no assistance towards the stability of the structure.

On a level with the base of the tank, projecting from the exterior of the tower, and carried on strong and elegant cast-iron brackets, is the gallery six feet in width, from the outer edge of which, on light iron columns, is carried the many-gabled conical Paxton roof which covers the tower. The total height of these stupendous edifices, from the ground line to the top ornaments on the roof, is 284 feet. From the same ground line to the floor of the projecting gallery is 214 feet, involving to the persevering visitor an ascent of no fewer than 400 steps, with only ten landings or rests on the floors previously mentioned. The reward in the prospect afforded will, however, amply repay the toil incurred, embracing as it does an horizon including part of six counties—viz., Middlesex, Kent, Essex, Bedfordshire, and Bucks—and including a panorama possessing, amongst other objects of interest, the Towers of London and Windsor, the woodlands of Essex, and the Downs of Epsom. The vision of the visitor from this height is also lifted over the grand plateau, or ridge, which separates the great lake with its antediluvian animals from the rest of the garden.

These magnificent towers, each of which contains 800 tons of iron, were designed by Mr. Brunel.

From the above simple statement it will be seen, that the arrangements for supplying the fountains with water are at once simple, complete, and based upon the most economical principles. The engine power employed is that of three hundred and twenty horses; the water itself is conveyed to and from the reservoirs in pipes varying from three feet to one inch in diameter; and the total weight of piping may be set down at 4000 tons, its length, roughly estimated, at ten miles.