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 INLAND NAVIGATION [europe difficult to drive by ordinary means. At the river water portion of the canal extended between Manchester most Weaver ten Stoney roller sluices are built, each 30 feet span, and Runcorn, while from the latter place to Garston it heavy stone and concrete piers and foundations; at was proposed to improve the upper Mersey estuary by with constructing training walls and dredging to form a deep Runcorn, where the river Mersey is narrow, a concrete sea central channel. Powers to construct the canal were wall 4300 feet long was substituted for the embankment. sought in the Session of 1883, when the Bill passed the At various points under the canal cast-iron siphon pipes Committee of the House of Commons, but was rejected by were laid to carry off any land drainage which was at a the Committee of the House of Lords. Brought forward lower level than the canal; the largest of these siphons again the next year, it was passed by the Lords but_ thrown were constructed to allow of the tidal and fresh water of river Gowy to pass under the canal at Stanlow Point, out by the Commons. The opposition from Liverpool the between Eastham and Ellesmere Port. Two 12-feet and the railway companies was very strong; to meet to siphons are there placed close together; built of cast-iron some extent that of the former, a continuation of the segments, they are each 400 feet long, and were laid on canal was proposed from Runcorn to Eastham along the concrete 4 feet below the bottom of the canal. Fiom Cheshire side of the Mersey, instead of a trained channel Runcorn to Latchford the canal is nearly straight, the in the estuary, and in this form the Bill was again intro- depth of cutting varying from 35 to 70 feet, partly in duced in the Session of 1885, and, notwithstanding strong rock, but generally in alluvial deposit. The whole length opposition, was passed by both Houses of Parliament. the canal passes through the New Red Sandstone formThe cost of this contest to promoters and opponents ex- of ation, with its overlying beds of gravel, clay, sand, and silt, ceeded £400,000, the various Committees on _ the Bill which gave much trouble during the progress of the work; having sat over 175 days. Owing to difficulties in raising retaining walls of stone and brickwork had to be built in the capital the works were not commenced until November these places to maintain the sides of the canal from slips jyid ixij ury from the wash of steamers. The canal from l887. ,, The total length of the canal is 35^ miles, and it may Latchford to Manchester is in heavy cutting through the be regarded as divided into three sections. From Eastham valleys of the rivers Mersey and Irwell. As these rivers to Runcorn it is near or through the Mersey estuary for are circuitous in course, only very small portions could be 12f miles, and thence to Latchford near Warrington, Si- utilized in forming the canal; a line as nearly straight as miles, it is inland ; both these sections have the same possible was therefore adopted, and involved many crosswater-level, which is raised by high tides. At Latchford ings of the river channels. During the whole progress of the locks stop tidal action, and the canal from that point the work these had to be kept open for the discharge of is fed by the waters of the rivers Mersey and Irwell to floods and land water, and in some places temporary cuts Manchester, 14 J miles from Latchford. The canal comconsiderable length had to be made for the same object. mences on the Cheshire side of the Mersey at Eastham, of In November 1890 and December 1891 high winter floods .about 6 miles above Liverpool. The entrance is well covered the whole of the river valleys, filling many miles sheltered, and adjoins a good low-water channel comthe unfinished canal and causing great damage to the municating with the Sloyne deep at Liverpool. Three of slopes. Altogether 23 miles of canal had to be pumped entrance locks have been provided close to and parallel out to enable the work to be completed. After the cuttings with each other, their length and width being 600 by 80, between the river channels were finished, the end dams 350 by 50, and 150 by 30 feet. These locks maintain the were removed, and the rivers Irwell and Mersey were water-level in the canal nearly to mean high-water level turned into the new channel now forming the upper (14 feet 2 inches above the Liverpool datum); when the portion of the ship canal. The total rise to the level of tide rises above that height the lock gates are opened and the docks at Manchester from the ordinary level of the the tide flows up to Latchford, giving on high spring tides water in the tidal portion of the canal below Latchford an additional depth of water of about 7 feet. On the locks is 60 feet 6 inches; this is obtained by an average ebb tide this water is returned to the Mersey through large of about 15 feet at each of the sets of locks at Latchsluices at Randles Creek and at the junction of the river rise ford Irlam (74 miles nearer Manchester), Barton (2 miles Weaver with the canal, the level of the canal thus being farther), and Mode Wheel (3| miles above Barton locks at reduced to its normal height. The canal throughout to Manchester has a minimum depth of 26 feet, the lock sills the entrance to the Manchester docks). For the greater part of this last length the canal is widened at bottom from being placed 2 feet lower to allow of the channel being dredged to a depth of 28 feet if necessary hereafter. The 120 feet, its normal width, to 170 feet, to enable vessels to at timber and other wharves in that part of the canal minimum width at bottom is 120 feet, allowing large vessels lie without interfering with the passing of large vessels to or to pass each other at any point on the canal; this width from the docks. The locks are in duplicate, one being is considerably increased at the locks and other parts. The slopes are generally about 1^ to 1, but are flatter through 600 feet long by 65 feet wide, the other 350 feet long by some portions ; in rock-cutting the sides are nearly vertical. 45 feet wide, with Stoney’s sluices adjacent. They are filled From Eastham to Runcorn the canal is alternately inland or emptied in five minutes by large culverts on each side and on the foreshore of the estuary, on which embankments with side openings into the lock. Concrete with facings were constructed to act as dams during the excavation of of blue Staffordshire bricks is largely used, and the copings, hollow quoins, and fender courses are of Cornisli the canal to keep out the tide, and_ afterwards to maintain sills, granite. The lock gates are constructed of greenhea t the water-level at low water in the estuary; both timber. The sluices near the locks take the place of the sides are faced with heavy coursed stone. The material weirs used in the old Mersey and Irwell Navigation; they for the embankments was principally clay excavated from are 30 feet span each, four being generally used at eacn the cuttings. In some places, where the foundation was set of locks. In ordinary seasons any water not usecl ° of a porous nature, sheeting piles of timber had to be lockage purposes passes over the tops of. the sluices, jhicn used At Ellesmere Port, where the embankment is 6200 kept closed ; in flood times the sluices are raised to a feet long on sand, 13,000 whole timber sheeting piles were are height which will pass off floods with a comparatively driven, to secure the base of the embankment on each side, small rise in the canal. There are eight hydraulic i they were 35 feet long, water jets under pressure through stallations on the canal, each having duplicate steam H inch wrought-iron pipes being used at the foot of each engines and boilers; the mams exceed 7 miles in iengtn, pile to assist the sinking of the piles, which were found 542

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