The Federal Government also participated in the merger by means of a voluntary share purchase.
The Pont–Vallorbe Railway (Chemin de fer Pont–Vallorbe), operated by the SOS, was purchased on 1 January 1891.
Studies prepared to support the construction of the tunnel had already been submitted by the SOS to the federal and cantonal authorities.
In 1891, JS, as a new entrepreneurial railway company, presented the Federal Council with a definitive project for the Simplon Tunnel.
On 25 November 1895, a treaty was signed with Italy for the construction of what would be the longest tunnel in the world.
The railway bridge over the Birs, which was built by Gustave Eiffel, collapsed below the village of Münchenstein under a train from Basel.
The route network of 937 km ran from Basel, Geneva and the Jura border crossings of Delle, La Chaux-de-Fonds, Les Verrières and Vallorbe to Brig and Lucerne.
In addition, the narrow-gauge Brünig Railway from Lucerne to Brienz was part of the 937 km-long route network.