Their division into seven great operating units--but always carefully correlated units--is only for the purposes of proper supervision. We have seen in a previous chapter how easily the efficiency of a single railroad may be thwarted by permitting it to grow to an untoward size. And before I am entirely done I shall hope to show you that even in a regional railway scheme, which applied to the United States might contemplate as many as forty different railroads--different in name and in operating organization--there must be a distinct effort toward a strong centralization of certain functions; notably financing, traffic solicitation and control, and the staff study of advanced operating methods of every sort. Along the first two of these lines the _reseaux_ of France have as yet accomplished but little. There has been up to the present time but little centralization of their control, although steps now are being taken toward that end. In the opinion of some of the wisest of Frenchmen to-day, such steps are not only the next in their railway development but certain to come to a successful head. Only the confusing problem of a single state-owned and operated system has prevented their being accomplished this long while. But in the standardization of operating methods and practices much already has been done in France. Four companies, the Etat, the Midi, the Paris, Lyons, and Mediterranean, and the Alsace-Lorraine have formed an organization with the rather formidable title of _L'Office Central d'Etudes du Materiel de Chemins de Fer_ for this purpose. This extremely active organization is divided into four departments, one in charge of tests, one for locomotive design, a third for car design, and the fourth to handle railway electrification.