alluvium carried off from these renders its lower channel inconstant;
the rest of the drainage area is occupied by crystalline rocks, over
the hard surface of which the water, undiminished by absorption,
flows rapidly into the streams. When the flood waters of two or
more tributaries arrive at the same time serious inundations result.
Attempts to control the river must have begun at a very early date,
and by the close of the middle ages the bed between Orléans and
Angers was enclosed by dykes 10 to 13 ft. high. In 1783 a double
line of dykes or turcies 23 ft. high was completed from Bec d’Allier
downwards. The channel was, however, so much narrowed that the
embankments are almost certain to give way as soon as the water
rises 16 ft. (the average rise is about 14, and in 1846 and 1856 it
was more than 22). In modern times embankments, aided by
dredging operations extending over a large number of years, have
ensured a depth of 18 ft. in the channel between La Martinière and
Nantes. Several towns have constructed special works to defend
themselves against the floods; Tours, the most exposed of all, is
surrounded by a circular dyke.
Various schemes for the systematic regulation of the Loire have been discussed. It has been proposed to construct in the upper valleys of the several affluents a number of gigantic dams or reservoirs from which the water, stored during flood, could be let off into the river as required. A dam of this kind (built in 1711) at the village of Pinay, about 18 m. above Roanne, and capable of retaining from 350 to 450 million cub. ft. of water, has greatly diminished the force of the floods at Roanne, and maintained the comparative equilibrium of the current during the dry season. Three other dams of modern construction are also in existence, one near Firminy, the other two near St Étienne.
LOIRE, a department of central France, made up in 1793 of the old district of Forez and portions of Beaujolais and Lyonnais, all formerly included in the province of Lyonnais. Pop. (1906) 643,943. Area 1853 sq. m. It is bounded N. by the department of Saône-et-Loire, E. by those of Rhône and Isère, S. by Ardèche and Haute-Loire, and W. by Puy-de-Dôme and Allier. From 1790 to 1793 it constituted, along with that of Rhône, a single department (Rhône-et-Loire). It takes its name from the river which bisects it from south to north. The Rhone skirts the S.E. of the department, about one-eighth of which belongs to its basin. After crossing the southern border the Loire runs through wild gorges, passing the picturesque crag crowned by the old fortress of St Paul-en-Cornillon. At St Rambert it issues into the broad plain of Fotez, flows north as far as its confluence with the Aix where the plain ends, and then again traverses gorges till it enters the less extensive plain of Roanne in the extreme north of the department. These two plains, the beds of ancient lakes, are enclosed east and west by chains of mountains running parallel with the river. In the west are the Forez mountains, which separate the Loire basin from that of the Allier; their highest point (Pierre sur Haute, 5381 ft.) is 12 m. W. of Montbrison. They sink gradually towards the north, and are successively called Bois Noirs (4239 ft.), from their woods, and Monts de la Madeleine (3822 to 1640 ft.). In the east the Rhone and Loire basins are separated, by Mont Pilat (4705 ft.) at the north extremity of the Cévennes, and by the hills of Lyonnais, Tarare, Beaujolais and Charolais, none of which rise higher than 3294 ft. Of the affluents of the Loire the most important are the Lignon du Nord, the beautiful valley of which has been called “La Suisse Forezienne,” and the Aix on the left, and on the right the Ondaine (on which stand the industrial towns of Chambon-Feugerolles and Firminy), the Furens and the Rhin. The Gier forms a navigable channel to the Rhone at Givors, and has on its banks the industrial towns of St Chamond and Rive-de-Gier. From Mont Pilat descends the Déôme, in the valley of which are the workshops of Annonay (q.v.). The climate on the heights is cold and healthy, it is unwholesome in the marshy plain of Forez, mild in the valley of the Rhone. The annual rainfall varies from 39 to 48 in. on the Forez mountains, but only reaches 20 to 24 in. in the vicinity of Montbrison.
The plains of Forez and Roanne are the two most important agricultural districts, but the total production of grain within the department is insufficient for the requirements of the population. The pasture lands of the plain of Forez, the western portion of which is irrigated by the canal of Forez, support a large number of live stock. Good pasturage is also found on the higher levels of the Forez mountains, on the north-eastern plateaus, where oxen of the famous Charolais breed are raised, and on the uplands generally. Wheat and rye are the leading cereal crops; oats come next in importance, barley and colza occupying a relatively small area. The vine is cultivated in the valley of the Rhone, on the lower slopes of the Forez mountains and on the hills west of the plain of Roanne. The forests of Mont Pilat and the Forez chain yield good-sized pines and wood for mining purposes. The so-called Lyons chestnuts are to a large extent obtained from Forez; the woods and pasture lands of Mont Pilat yield medicinal plants, such as mint. Poultry-rearing and bee-keeping are considerable industries. The department is rich in mineral springs, the waters of St Galmier, Sail-sous-Couzan, St Romain-le-Puy and St Alban being largely exported. The chief wealth of the department lies in the coal deposits of the basin of St Étienne (q.v.), the second in importance in France, quarrying is also active. Metal-working industries are centred in the S.E. of the department, where are the great manufacturing towns of St Étienne, Rive-de-Gier, St Chamond and Firminy. At St Étienne there is a national factory of arms, in which as many as 10,000 have been employed; apart from other factories of the same kind carried on by private individuals, the production of hardware, locks, edge-tools, common cutlery, chain cables for the mines, files, rails, &c., occupies thousands of hands. Cast steel is largely manufactured, and the workshops of the department supply the heaviest constructions required in naval architecture, as well as war material and machinery of every description. The glass industry is carried on at Rive-de-Gier and St Galmier. St Étienne and St Chamond are centres for the fabrication of silk ribbons, elastic ribbons and laces, and the dressing of raw silks. Between 50,000 and 60,000 people are employed in the last-named industries. The arrondissement of Roanne manufactures cotton stuffs, muslins and the like. That of Montbrison produces table linen. The department has numerous dye-works, flour-mills, paper works, tanyards, brick-works, silk-spinning works and hat factories. It is served by the Paris-Lyon railway, Roanne being the junction of important lines from Paris to Lyons and St Étienne. Within the department the Loire is hardly used for commercial navigation; the chief waterways are the canal from Roanne to Digoin (13 m. in the department), that from Givors to Rive-de-Gier (7 m.) and the Rhone (7 m.).
Loire comprises three arrondissements—St Étienne, Montbrison and Roanne—with 31 cantons and 335 communes. It falls within the region of the XIII. army corps and the diocèse and académie (educational circumscription) of Lyons, where also is its court of appeal. St Étienne is the capital, other leading towns being Roanne, Montbrison, Rive-de-Gier, St Chamond, Firminy and Le Chambon, all separately noticed. St Bonnet-le-Château, besides old houses, has a church of the 15th and 16th centuries, containing paintings of the 15th century; St Rambert and St Romain-le-Puy have priory churches of the 11th and 12th centuries; and at Charlieu there are remains of a Benedictine abbey founded in the 9th century, including a porch decorated with fine Romanesque carving.
LOIRE-INFÉRIEURE, a maritime department of western
France, made up in 1790 of a portion of Brittany on the right
and of the district of Retz on the left of the Loire, and bounded
W. by the ocean, N. by Morbihan and Ille-et-Vilaine, E. by
Maine-et-Loire and S. by Vendée. Pop. (1906) 666,748. Area
2694 sq. m. The surface is very flat, and the highest point, in
the north on the borders of Ille-et-Vilaine, reaches only 377 ft.
The line of hillocks skirting the right bank of the Loire, and
known as the sillon de Bretagne, scarcely exceeds 250 ft.; below
Savenay they recede from the river, and meadows give place
to peat bogs. North of St Nazaire and Grande Brière, measuring
9 m. by 6, and rising hardly 10 ft. above the sea-level, still supplies
old trees which can be used for joiners’ work. A few scattered
villages occur on the more elevated spots, but communication
is effected chiefly by the canals which intersect it. The district
south of the Loire lies equally low; its most salient feature is
the lake of Grandlieu, covering 27 sq. m., and surrounded by
low and marshy ground, but so shallow (612 ft. at most) that
drainage would be comparatively easy. The Loire (q.v.) has a
course of 70 m. within the department. On the left bank a
canal stretches for 9 m. between Pellerin, where the dikes which
protect the Loire valley from inundation terminate, and Paimbœuf,
and vessels drawing 17 or 18 ft. can reach Nantes. The
principal towns on the river within the department are Ancenis,
Nantes and St Nazaire (one of the most important commercial
ports of France) on the right, and Paimbœuf on the left. The
chief affluents are, on the right the Erdre and on the left the
Sèvre, both debouching at Nantes. The Erdre in its lower
course broadens in places into lakes which give it the appearance
of a large river. Four miles below Nort it coalesces with the