Rhine

Holland.

In Holland its course is again westward. Almost immediately after entering this country the river divides into two arms, the larger of which, carrying off about two-thirds of the water, diverges to the west and is called the Waal, whilst the smaller, which is still called the Rhine, sends off another arm, the Ijsel, to the Zuider Zee. The Waal is joined on the left by the Maas (Meuse) and after passing Nijmegen and Dordrecht enters the North sea by way of the Hollandsch Diep.

Further subdivision takes place and the entire district between the Waal and the Ijsel in reality belongs to the delta of the famous river, built by alluvium from the Alps and Britain in pre glacial times, covered by glacial deposits and latterly in places again covered with mud of the great river.

Navigation.

The Rhine has been one of the chief waterways of Europe from the earliest times ; and its channel has been com paratively easy to keep open. The position of the river is highly favourable for the development of its trade. It flows through regions rich in mineral resources and the most populous of Europe, to discharge into one of the most frequented seas opposite Great Britain. Besides serving as a natural outlet for Germany, Belgium and Holland, it is connected with a great part of cen tral and southern France by the Rhine-Rhone and the Rhine Marne and other canals, and with the basin of the Danube by the Ludwigskanal.

In 1831 a system was agreed upon which practically gave free navigation to vessels of the riverine states, while imposing a moderate tariff upon foreign ships. After the war of 1866, Prus sia negotiated with Baden, Bavaria and Hesse-Darmstadt with a view to the removal of all tolls, but it was not until 1868 that the river was thrown open without any restriction. The manage ment of the channel and navigation was then vested in a central commission meeting at Mannheim each year. The treaty of Ver sailles (192o), while deciding that the act of Mannheim should under certain conditions continue to regulate navigation on the Rhine, put the vessels of all nations on the same footing as ves sels belonging to the Rhine navigation. The composition of the central commission was modified by the admission of Switzerland, Belgium, Great Britain and Italy. The Versailles terms were com pleted in 1921 by a protocol of adhesion on the part of the Nether lands. The Barcelona convention (1921) applies to the Rhine and takes precedence, if necessary, over the Mannheim convention. For details of the international regime see INLAND WATER TRANS PORT.

The introduction of steam has greatly increased the shipping on the Rhine, and small steamers ply also on the Main, Neckar, Maas and Moselle. The steamboat traffic has especially encour aged the influx of tourists. Large passenger boats ply regularly between Mainz and DUsseldorf, and sometimes extend their jour ney as high up as Mannheim, and as far in the other direction as Rotterdam. The river is navigable without interruption from

Basle to its mouth, a distance of 55o m. Above Spires, however, the river craft are comparatively small. Between Basle and Stras bourg the depth of water is sometimes not more than 3 ft., be tween Strasbourg and Mainz it varies from 5 to 25 ft., while below Mainz it is never less than 9 or Io feet. The efforts of the river authorities are being directed to the deepening and improvement of the navigable channel from the sea to Strasbourg. Two navig able channels of sufficient depth for all vessels which ply up and down that part of the stream, have been blasted out where rapids occur near Bingen. The difficulties in the river channel above Strasbourg, which are augmented by a steep gradient and swift current, are such that any plans to improve the river in this stretch are too expensive to be feasible. A parallel canal in the lateral plains of Alsace td the left is the solution proposed. It will begin at Huningue, where a huge dam will be constructed to regu late the water, and continue to Strasbourg, having at each of its eight locks a gigantic power plant. The total power generated by the plants should be about 700,000 h.p. which will be available for the industrial establishments in the region, and help also to pay the cost of the project.

At the chief river-mouth ports, Rotterdam, Antwerp and Amsterdam, merchandise is transferred from ocean steamers to river steamers or vice versa. Nearly three-fourths of the Rhine traffic passes through Rotterdam which is the only one of these ports directly on the Rhine. Amsterdam is connected by the Merwede canal and the difficulties of navigation in the canal have considerably reduced this port's share of the traffic. The passage to Antwerp is indirect and plans are going forward to connect the Belgian city directly with the Rhine by extending the Scheldt-Meuse canal to Ruhrort. Duisburg, Ruhrort and Cologne are the principal export ports in the central reaches of the river. They have expanded rapidly with the exploitation of the coal mines and the building up of the great industrial region of the Ruhr valley. Capacious harbours have been formed in the low lying basins of the valley, and river facilities are supplemented by the Herne canal which traverses the heart of the Ruhr section and continued as the Ems canal connects with the intricate inland waterway system of central and northern Germany. The chief ports of the Upper Rhine—Mannheim, Rheinau, Ludwigshafen and Strasbourg—are places of transfer from river to railway. They deliver and collect from the southern markets of Germany and Switzerland. From Mainz there is passage via the Main river and the Ludwig canal, which it is expected to improve or sup plement, to the Danube river.