The SNCF BB 1280 class were a class of 600 V DC 4 axle Bo′Bo′ electric locomotives, formerly Compagnie du chemin de fer de Paris à Orléans machines (originally PO E.1 to E.13), initially built for an underground section of line connecting the Gare d'Austerlitz to the Quai d'Orsay in inner Paris. The locomotives were converted for 1500 V DC use in the 1930s, and renumbered PO E.281 to E.293. They were absorbed by the SNCF, and operated as shunters until the late 1960s. History At the end of the 19th century the Compagnie du chemin de fer de Paris à Orléans (PO) was seeking to extend its railway into a more central location in Paris: an extension from the Gare de Austerlitz to the new Gare du Quai d'Orsay was constructed, including covered sections; the new section was similar to the recently constructed Baltimore Belt Line (USA), constructed by the Baltimore and Ohio Railroad (B&O) and operated by electric locomotives built by General Electric, which had worked well, and achieved speeds of 80 km/h. Eight locomotives were ordered for the new line, delivered between 1900 and 1904, numbered E1 to E8, with electrical equipment from GE, and mechanical equipment and structural parts manufactured by Blanc-Misseron. The line was electrified by 600 V DC, supplied by a third rail, with overhead collection via a mini-pantograph in the Orsay tunnel. Unlike the B&O locomotives the PO units used geared drive, rather than the co-axial gearless motor drive of the 1896 B&O machines. Locomotive E.1 was exhibited at the 1900 Exposition Universelle in Paris. The first eight units were a single cab steeplecab design. Further units were acquired as the system's electrification spread beyond the initial Orsay-Austerlitz line; five units were acquired, with a twin cab design, with a baggage compartment (locomotives-fourgon). In service the locomotives were used throughout the PO system where electrified; the initial specifications of the design, matching those used for the tunnel shuttle service on the Baltimore Belt Line were too low geared for the general network, and in 1904 seven locomotives were upgeared and the top speed raised to 100 km/h. In the late 1920s/1930s 1500 V DC began to be used on the PO rail system; the locomotives were converted for 1500 V operation at workshops at Vitry-sur-Seine using a Metadyne for traction control. A new pantograph as well as sand boxes were added. After conversion