Yes, " The Mail ", AKA The Ghost Trains of SP's Overland Route ( also a book of the same name ) were trains # 21 & 22. The Overland Mail was a U.P. named train, while # 21 & 22 did not have official timetable names for most of their careers. By the early 1960's they were the only remaining scheduled passenger runs across Northern Nevada in daylight hours. Alas, the end of 1st Class Postal Mail rail services in 1967 was the death of these runs. I highly recommend the book (available from Espee Tech ) as an informative and entertaining look at the history & operations of Trains # 21 & 22.