Does anyone know what symbol/symbols PC used in moving empty hoppers back from the lakes to Shire Oaks/W. Brownsville. My PC symbol books don't show much in this traffic lane, except an XEL from Ashtabula to Ellsworth Br. listing in 1974. Prior listings show XELs as Enola to Scully hoppers. There are many listings for hoppers out of Enola back to the mines via Cresson/Pitcairn/Shire Oaks/Monongahela Ry listed as XEC/XEP/XEO/XEM respectively. Any help appreciated.