1893 Columbian Exposition, all-over light olive green publicity advertising cover showing Landing of Columbus scene from Sewell-Clapp Mfg. Co. bearing 2Ā¢ Columbian (231), s.e. at top, tied by "Chicago Ill. Jul 31 '93" machine cancel to local Chicago address; upper right rounded corner, otherwise Very Fine. EstimateĀ $150 - 200. $0 (Image)