RPO CANCELLATION QUESTION

[Charles H Bogart]

I have a letter mailed by a soldier traveling from Jefferson Barracks, Missouri to Camp Wallace Texas -- the cancelation is a partial -- in the 9 o'clock position it reads "NEW" in the 3 o'clock "W.N.D." and in the 6 o'clock "RPO" In the center it reads "TR 5 Mar 22 1941" Does anyone know what railroad and train this letter was canceled on?

[Georgegan001]

very goog

[wjstix]

There have been books written listing all the RPO routes in the US, but doesn't appear to be a complete listing online anywhere. One thing that can be confusing is the RPO cancellation stamp shows the mail line or route the RPO was on - not the railroad, so in this case W.N.D would not represent the railroad's initials.