Loire

Loire (anc. Liger), the longest river in France, has its source in the Cévennes, in the department of Ardèche, at an elevation of 4511 feet, flows in a north and north-western direction through the centre of France as far as Orleans, where it bends round to the south-west and continues on to Tours; thence it follows, in general, a western course to its embouchure in the Bay of Biscay. It is tidal to Nantes (q.v.), 35 miles from its mouth. Entire length, 620 miles. It becomes navigable a little above Roanne, 550 miles from the sea. At one time the depth of the water at its mouth was 19½ feet at ebb-tide; now it is only about 6½ feet. This is due to the vast quantity of sedimentary matter the river brings down with it. To the same cause are due the numerous islands that obstruct its lower course and the sandbanks that lie athwart its mouth. The Loire is notorious for the destructive inundations it causes, although the lower part of its course is protected by large dykes or levées, 20 feet high. The principal tributaries are the Nièvre and the Maine (which is formed by the Sarthe, its affluent the Loir, and the Mayenne) on the right; and the Allier, Cher, Indre, and Vienne, on the left. The Loire is canalised along considerable stretches of its course, and is connected with the Seine, the Saône, and the harbour of Brest by canals. Its valley is extremely fertile. Area of drainage basin, 44,450 sq. m. See The Seine and the Loire, with sixty-one illustrations by Turner (new ed. 1886).