(1877-1916 Pittsburgh Exposition Society Exposition & Fair) Pittsburgh Exposition Society. Imprint on two 1877 covers franked with 3¢ Bank Note, cancelled by blue cork with matching "Allegany, Pa." cds, each with original enclosure showing wonderful illustrated design of Exposition Building, covers slightly reduced at right, one 3¢ creased, F.-V.F., a very rare pair. Estimate  $200 - 300. $0 (Image)

(1877-1916 Pittsburgh Exposition Society Exposition & Fair) Fourth Grand Exposition & Fair of the Pittsburgh Exposition. Lovely all- illustrated design showing the Expo. Grounds on reverse of advertising cover franked with 1¢ Bank Note (defective) tied by "Allentown, Pa." cds, Extremely Fine and attractive. Estimate  $75 - 100. $0 (Image)