(Route 6006) Caddo, red straight-line handstamp on folded letter datelined "Shreveport 13 April 1851" addressed to New Orleans La., entered mails with red "New Orleans La. Apr 16" cds and matching "Way 11 Cents" rating handstamp; docketing lightened at top, Very Fine, Illustrated in Milgram on page 138. Milgram No. 154  Estimate $400 - 600. A large number of steamboats would have been used by the Post Office Department for the three times a week route that was individually contracted by the trip during its operation from July 1847 to June 1851."Caddo" of 188 tons was built in 1848 at Louisville Ky. $0 (Image)