Two 1875 2c vermilion Jackson stamps and one 1873 6c dull pink Lincoln on cover sent from Chicago on May 1, 1876. Stamps paying double the international rate are canceled with blue Chicago postmark and "killer" cancellation typical to Chicago during that era. Also on front is circular red "PAID ALL" Chicago marking. Reverse has May 15 "Kingston-On-Thames" receiving backstamp. A neat Trans-Atlantic cover with nice Chicago postal markings.