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CANALS

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INLAND

the narrow Worcester and Birmingham Canal, which is now the property of the Gloucester and Berkeley Canal, the Midland Railway Company having failed to get powers to purchase it. At present the large Severn barges have to tranship their cargoes into small canal boats at Worcester, and the question of increasing the size of the canal to Birmingham is under consideration. The Aire and Calder Navigation was authorized by an Act passed in 1698; other Acts of later date gave additional powers for enlarging the navigation, and now one 'calder. ^ ^he best English waterways, giving communication between Lancashire and Yorkshire and the ports of Goole and Hull. Its original capital was £150,000, but the amount expended to the year 1898 was <£2,761,807. Its total length is 85 miles, part river and part canal, with 31 locks. Commencing at Goole, it terminates at Leeds with a junction with the Leeds and Liverpool Canal, thus forming a continuous navigation from the east to the west coasts. At Castleford it has a branch to Wakefield, where it joins the Barnsley Canal. Originally the navigation was only 3 feet 6 inches deep, but since 1860 great improvements have been carried out, the locks being made 215 feet long, 22 feet wide, with 9 feet of water on the sills. All overhead bridges have been enlarged to the width of the locks; vessels carrying cargoes of 170 tons can now use the navigation, and three 50-ton barges can pass the locks together. Merchandise is generally carried in barges towed in trains by steamers, which also carry goods, but the large coal traffic is conveyed in trains of boat compartments, either towed or pushed by steamers, on a system designed by Mr W. H. Bartholomew. The boats, except the leading one, which has an ordinary bow, are nearly square in shape; they are coupled together by knuckle joints fitted into hollow stern-posts, and they can thus move laterally or vertically; a wire rope in tension on each side of the boat enables the train to be steered. No boat crews are required, the crew of the steamer regulating the train. If the boats do not exceed eleven in number, they can be pushed, but beyond that number they are towed. Each compartment carries 35 tons, and the total weight in a train varies from 700 to 900 tons. On the arrival of a train at Goole the boats are detached, and are each taken over submerged cradles under powerful hydraulic hoists, which lift boat and cradle sufficiently high to enable it to be turned over, and discharge the whole cargo at once into a shoot, and thence into seagoing steamers. Goole has become an important port owing to the improvements of the Aire and Calder Navigation Company, who have constructed docks of 24 acres in extent to give accommodation to foreign and coasting steamers. The River Weaver Navigation is about 20 miles in length. This river rises in the south-west corner of Weaver Cheshire, passing through the salt districts of Winsford and Northwich, and joins the Mersey at Irodsham. It is made navigable between those places under the powers of an Act of 1721, which ordered that any profits were to be employed in repairing public bridges, and meeting other public charges in the county of Chester; considerable sums have been paid accordingly. Subsequent Acts enabled a canal to be made, 4 miles in length, to avoid the lower tidal portion of the river, and to obtain a better entrance on the Mersey at Weston Point, where docks have been constructed. Other cuts were made to shorten the course of the river, and the depth was increased to 7 feet, enabling craft of 100 tons to use the navigation, their cargoes being principally salt for shipment at Liverpool An Act was obtained in 1866 authorizing further improvements, which have since been

NAVIGATION

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completed, with the result that it is the best navigation in England for small coasters and large barges. The locks are in pairs, the largest being 220 feet long by 42 feet wide, with 15 feet depth on the sills; at present the river dredging has not gone beyond 10 feet 6 inches in depth. Canalized rivers have the advantage of a good supply of water, even for large locks, and on the river Weaver there are also large natural reservoirs, formed by the subsidence of the ground owing to salt workings and brine-pumping. The locks have intermediate gates, so as to shorten them when only single vessels have to pass; otherwise the locks can take a steamer, carrying cargo and towing barges, with total cargoes amounting to 600 to 800 tons. The lock gates are worked by turbines, thus utilizing the fall at the locks and the ample supply of water. The effect of the new works has been to secure the whole of the large export salt traffic to Liverpool and other ports, the railways not being able to compete with the low cost of carriage on such an improved waterway. France.—M. Freycinet, when Minister of Public Works, stated, in a report on the rivers and canals of France : “ Navigable waterways play an important part in the production of the wealth of a country. It has been found that navigable waterways and railways are not destined to supplant but to support one another. Each has its particular attributes. Railways take the least cumbrous traffic—that which requires speed and regularity and bears most easily the cost of carriage. Waterways take heavy goods of low value, and their mere existence checks and moderates the rates on goods which are sent by railway." The principle thus laid down has been fully accepted in France, where the waterways, 7459 miles in length, are the property of the State, only 158 miles remaining in other hands. The navigations are divided into two classes, main and secondary, the main ones having a minimum depth of 6Jr feet, with locks 126 feet long and 17 feet wide; the second class are of smaller dimensions. The improvements in the river Seine have made it a most important waterway. Not to mention the embankments and training walls, which with dredging have had such important results in enabling large steamers to reach Rouen, the upper portion of the river from that place to Paris affords a good example of a modern canalized river, although it is so winding that its length of 150 miles between Rouen and Paris is more than double the distance between those cities measured in a straight line. On this portion of the Seine locks and weirs had been constructed between 1838 and 1866, but they only gave a navigable depth of 5 feet. In 1878 new works were authorized to secure a depth of lOJ feet, and so enable vessels of 800 to 1000 tons to reach Paris. These works have been completed, dividing the river into nine reaches by locks and weirs of large size, the level of the highest pound being about 85 feet above high water of the lowest tides which reach the first lock above Rouen. Although the railway competition is severe, the lower cost of water carriage secures a traffic of over four million tons a year. The navigation is toll-free, and the improvements have cost the State <£2,500,000. At Rouen the cargoes of shipping for Paris and the interior are discharged into lighters, carrying from 300 to 900 tons each, which are towed by steam tugs; the locks are able to take trains of barges which pass up the first-class navigations beyond Paris. Steamers trade between London and Paris, but their size is restricted by several low bridges which have yet to be altered. The river Saone has been canalized for a length of 231 miles as a first-class waterway, with a depth of 6|- feet. The most important canals in France have been enlarged to a similar depth, the locks being 126 feet long and 17 feet wide, and barges capable of carrying 300 tons now traverse S. II. — 70