From the recording The Songs Remember
This song remembers the time of the Great Depression in America when out-of-work bankers, lawyers, merchants, and citizens hopped the southbound freight trains in search of jobs in Birmingham to send money back home. The were the first "American Hobos", most dressed in business suits and wing-tip business shoes.
Blue mountain song, somethin' wrong again. Blue lights on the mountain. Short on cash, long on hope, got on that midnight flyer. There's money down in Birmingham, far from Caroline, far from darlin' Jessie, cryin' 'neath the pine.