P.O. Midi 
advertising bookmark, 1930s, pre-stamped card, 187 mm

The Chemin de Fer de Paris à Orléans et du Midi, often abbreviated to PO-Midi, was an early French railway 
company. It was formed in 1934 following the merging of the Chemin de Fer de Paris à Orléans and the
 Chemin de  Fer du Midi. In 1937 it was nationalised to become part of the Societé Nationale des Chemins
de Fer Français (SNCF).