Sewell-Clapp Manf'g Co./Envelope Factory. All over advertising design on 1893 cover showing Landing of Columbus, similar to the design of the 2¢ Columbian in blue green, franked with 1893 3¢ Columbian (s.e. at bottom) tied by Chicago machine cancel, reverse with all over ad text, Extremely Fine. Estimate  $100 - 150. $0 (Image)