clear strike in black on ca. 1878 cover to Dixon, Illinois, deposited without postage, "Chicago Ill. S.D. Sta. Feb 12 6PM" postmark, blue pencil "3c" due, backstamped February 13, opened at top to find the address of the sender and sealed with an official seal (OX1, faults), very fine appearance, the earliest recorded "Returned for Postage" handstamp from Chicago, illustrated in Piszkiewicz (page 477)