International Aviation Meet, Chicago Lake Front, August 12-20, 1911. Blue on yellow orange label on front and reverse of Aero Club of Illinois corner card cover, franked with 2¢ red tied by "Chicago, Ill., Jul 14, 1911" machine postmark; faint cover tone band at bottom, still Very Fine, only a few on cover usages known. Estimate  $200 - 300. $0 (Image)