The Nord-Sud Company (English: North-South; ) was an operator of underground trains in Paris established in 1904, which built two lines, Line A (now Line 12) and Line B (now part of Line 13) and had a concession to build a third. It was taken over by the Compagnie du chemin de fer métropolitain de Paris (CMP) in 1930 and incorporated into the Paris Métro.
History
Concept
The north–south was the initiative of Jean-Baptiste Berlier, an engineer from Lyon trained at the École Nationale Supérieure des Mines de Saint-Étienne, who had previously attempted to build an underground tubular tramway in 1897. In 1901 he proposed, with the financial support of Xavier Janicot, to construct a line between Montparnasse and Montmartre passing through the Gare d'Orsay and Gare Saint-Lazare through two parallel tunnels, consisting of a series of metal hoops, at a similar depth to the London "tube". This method of construction was intended to allow more direct routes to be taken, unconstrained by the street pattern. The City of Paris wanted to try this experiment and he obtained the concession on 28 December 1901. The charter provided that the costs of construction and rolling stock would be borne entirely by the concessionaire, although in the case of the CMP's lines, the City of Paris had fully funded the network infrastructure.
The concession covered three proposed lines: line A would join Montmartre to Montparnasse as an additional north–south line to the west of line 4 line B would serve the north-west of Paris only by connecting Saint-Lazare station to Porte de Clichy and Porte de Saint-Ouen line C would serve the south-west only by connecting Montparnasse station to Porte de Vanves.
Financing and authorisation
The Société du chemin de fer électrique souterrain Nord-Sud de Paris (French for "Paris North-South underground electrical railway company", abbreviated to the Nord-Sud company) was created in July 1902 and replaced Berlier and Janicot as the concessionaire. The substitution was approved by a decree on 26 March 1907. The company was affiliated with the Omnium Lyonnais and formed with a capital of two million francs, the capital required increased gradually to seventy-five million francs in 1910, after the raising of thirty-five million francs of capital in 1909.
The Nord-Sud aimed to distinguish itself from its rival by the high-quality decoration of its stations and trains as well as by certain technical differences. Line A between Montmartre and Montparnasse would provide substantial traffic in the absence of an existing line on this route. This was a real threat to the tram companies and to the CMP, which objected to the potential competition. Despite the delay caused by the CMP's opposition the line between Montmartre (Place des Abbesses) and Montparnasse was declared of "public utility" (a key step in the French legal process for authorising construction) on 3 April 1905. A law of 19 July 1905 completed the concession by declaring of public utility the complementary sections from Montparnasse to Porte de Versailles and the branch to Saint-Lazare and the Porte de Saint-Ouen. The extension of from Abbesses to Jules Joffrin was declared of public utility on 10 April 1908. The stretch from La Fourche to Porte de Clichy was declared of public utility on 11 June 1909. On 24 January 1912 the extension from Jules Joffrin to Porte de la Chapelle was approved and finally the line C from Montparnasse to Porte de Vanves was approved on 19 July 1912. This brought the total length of the network approved under the concession to .
Construction
During early studies, it appears that construction of a deep underground railway as in London quickly proved impossible because of the different nature of the ground in Paris. Beneath the water table, soil is actually very diverse in nature and waterlogged, making it impossible to build a metal tunnel. Establishing the line at an even greater depth would have been more expensive.
The lines were built well above the water table, like those of the CMP, just below the road, which meant that the line had a particularly tortuous alignment contrary to the original plans. The characteristics of the railway provided the specifications are similar to those of the CMP lines in relation to loading gauge, maximum grades and the minimum radius of curvature.