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INL AND NAVIGATION 543 the pressure being 700 lb to the inch. They work the The canal being virtually one long dock, wharves at cranes, lifts, and capstans at the docks, lock gates, and various points have been erected to enable chemical or culvert sluices, coal tips, swing bridges, and aqueduct. manufacturing works to be carried on, widenings being At Barton, near Manchester, the Bridgewater Canal provided where necessary. At Ellesmere Port coal tips crossed the river Irwell on the first navigable aqueduct and sheds have been erected, and the canal is in direct constructed in England; it was the work of Brindley. communication with the docks there as well as at Weston Since it was only built at sufficient height to allow of Point and Runcorn, where a large trade is carried on with barges passing under it, means had to be found to allow re >0 er es an a ei3 • °r(^S 1^branches ^ ^^ ^from the d the Cheshire salt the districts. of this important canal being maintained, and yet to At Partington railways connect canal permit large steamers to use the ship canal below it. with the Yorkshire and Lancashire coal-fields, and the canal Brindley’s canal is on one level throughout its whole is widened out 65 feet on each side for six hydraulic coal length, and as its water supply is only sufficient for the tips. At Mode Wheel there are extensive abattoirs and flight of locks by which it descends at Runcorn to the lairages, erected by the Manchester Corporation; also large Mersey, locks down to the ship canal would have involved petroleum oil tanks, graving dock and pontoons, cold-air the waste of a lock of water on each side and caused meat stores, and other accommodation for traffic. At serious delay to the traffic. Sir E. Leader Williams sur- Manchester the area of the docks is 104 acres, with 152 mounted the difficulty by means of a swing aqueduct for acres of quay space, having over 5 miles of frontage to the Bridgewater Canal, which when closed allows of the the docks, which are provided with a number of threetraffic passing as heretofore, while it is opened to allow of storey transit sheds, thirteen seven-storey and seven fourships crossing it on the lower level of the ship canal. The storey warehouses, and a large grain silo. The London water in the swing portion of the aqueduct when opened and North-Western and Lancashire and Yorkshire Railway is maintained by closing gates at each end, similar gates Companies have made branch lines to the docks, the railbeing shut at the same time across the fixed portion of the ways and sidings at which are over 30 miles in length. aqueduct. The swing portion is a large steel trough Much traffic is also carted, or dealt with by inland canals carried by side girders, 234 feet long and 33 feet high in in direct communication with the docks. The substitution the centre, tapering 4 feet to the ends • the waterway of a wide and deep canal, nearly straight, for comparatively is 19 feet wide and 6 feet deep. The whole works on a shallow and narrow winding rivers, and the use of large central pier with similar arrangements to the largest swing sluices in place of fixed weirs to carry off the river water, bridges on the canal j it has two spans over the ship canal have been of great advantage to the district in greatly of 90 feet each. It is somewhat singular that the first reducing the height of floods. fixed canal aqueduct in England should, after the lapse of The total amount of excavation in the canal, docks, 136 years, be replaced by the first swing aqueduct ever and subsidiary work amounted to over 54 million cubic constructed. The swing aqueduct is moved by hydraulic yards, nearly one-fourth of which was sandstone rock; power, and has never given any trouble in working, even the excavated material was used in forming the railway in times of severe frost. The weight of the movable deviation embankments, filling up the old beds of the portion, including the water, is 1600 tons. rivers, and raising low lands near the canal. As many The manner of dealing with the five lines of railways men were employed on the works as could be obtained, that were cut through by the canal was one of importance, but the number never exceeded 17,000, and the greater both in the interests of the travelling public and the trade part of the excavation was done by about eighty steam on the canal; they are all important lines, including the navvies and land dredgers. For the conveyance of excavamain line of the London and North-Western Railway near tion and materials, 228 miles of temporary railway lines Warrington, with its important route to Scotland. Hitherto were laid, and 173 locomotives, 6300 waggons and trucks, no such alteration of a railway had been sanctioned by and 316 fixed and portable steam-engines and cranes were Parliament, and it was only the importance of a ship canal to Manchester that secured the requisite power against the employed, the total cost of the plant being nearly The expenditure on the works, including strong opposition of the railway companies. Swing bridges, £1,000,000. plant and equipment, to 1st January 1900, was £10,327,666! although in use on some lines to cross navigations, are The. purchase of the Mersey and Irwell and Bridgewater dangerous and inconvenient, and high-level deviation lines Navigations (£1,786,651), land and compensation were adopted for each railway crossing the canal. Em(£1,223,809), interest on capital during construction bankments were made close to and parallel with the old (£1,170,733), and parliamentary, superintendence, and ines, commencing about a mile and a quarter from the canal on each side, the canal itself being crossed by via- general expenses brought up the total amount to ducts which give a clear headway of 75 feet at ordinary £15,248,437. The traffic on the canal has gradually increased from water-level. Vessels trading on the canal with high masts 925,659 tons in the year 1894 to 2,778,108 tons in 1899. are provided with telescopic or sliding top masts. The After its opening considerable reductions were made in gradients on the railways rising up to the viaducts are 1 the railway rates of carriage and in charges at the Liverm . 5. The span of the viaducts is so arranged as to pool docks in order to meet the lower cost of conveyance maintain^ the full width of the canal for navigation; and by shipping passing up it. The result has been of great as the railways generally cross the canal on the skew, this advantage to the trade of Lancashire and the surrounding necessitated girders in some cases of 300 feet span. There are nine main roads requiring swing bridges across the districts, and the saving in the cost of carriage, estimated canal; all below Barton have a span giving a clear water- at £ 100,000 a year, assists manufacturers to meet the way of 120 feet. The width of these bridges varies with competition of their foreign opponents who have the the importance of the roads from 20 to 36 feet, and they advantage of low rates of carriage on the improved waterways of America, Germany, France, and Belgium. Before nS rUC e< s ee i rmA° ^ each. ^ ^ They ^ ^work their on weight from 500 to the construction of the canal, large works had left Man0 tons a liveranging ring of conical castnon rollers, and are moved by hydraulic power supplied chester to establish themselves at ports like Glasgow, where they could save the cost of inland carriage. Since its J steam, gas, or oil engines. The Trafford Road Bridge opening, new industries have been started at Manchester a .i!6 canal; ^°C^S being Manchester the heaviest bridge and along its banks, warehouses and mills that were foron tbe of extra is width, it weighs swing 1800 tons. merly empty are now occupied, while nearly 10,000 new