5c black on rose 'SERVICIO POSTAL FERRO' postal stationery envelope (H&G B1) with part strike of 'FRANCISO A. GUZMAN' company cachet on reverse used with fine strike of oval FERROCARRIL DE LA SABANA BODEGA DE BOGOTA cancel in purple dated SET 10 1891 on front. Addressed to FACATATIVA. Part of backflap missing but otherwise a very rare envelope correctly used on the railway.