sentences:  The SS was then founded as a private company to use these lines.In 1890 the SS began to use the lines previously run by the defunct Nederlandsche Rhijnspoorweg-Maatschappij, and in 1919 it also began to use lines run by the Nederlandsche Centraal-Spoorweg-Maatschappij.The company was formally merged with the HSM to form the Nederlandse Spoorwegen in 1938, although independent operations had stopped earlier.