CSA 11, 10¢ blue horizontal strip of three and a single in different shades, small flaws, manuscript canceled and tied by light blue PETERSBURG VA postmarks on cover to Capt. F. P. Leavenworth in Shreveport, La. with manuscript "Via Meridian" manuscript directive, with colorless embossed Collegiate Seminary for Young Ladies, Petersburg, Virginia, Rev. A.J. Leavenworth, Principal corner card (Dietz Type I) at top left. A RARE TRANS-MISSISSIPPI EXPRESS COVER USE ON AN ADVERTISING COVER.  Ex Baum. $1,800. Listed in both Advertising and Miscellaneous, Section 1. 

Captain Frederick Peabody Leavenworth (1883-1920): This Trans-Mississippi Express Mail cover surfaced in 2006 and is one of only two known express covers with a college imprint. The envelope was addressed to Captain Frederick Peabody Leavenworth and was sent by Reverend Abner Johnson Leavenworth, father of Capt. Leavenworth and principal of the Collegiate Seminary for Young Ladies. F. P. Leavenworth was commissioned as a captain in early 1862; he served as Ordnance Officer under General E. Kirby Smith in the Trans-Mississippi Department.