The study by Judith McCulloh of 160 texts concluded that "The Longest Train" cluster and the "In the Pines" cluster once constituted two different songs that have been yoked (folked?) together. See "Long Steel Rail," Norm Cohen, p. 493.

Since everyone seems to want to add an interpretation-
Eliminating the train and the railroad accident, that leaves the In the Pines cluster, which I could speculate is a murder ballad. The boy found that the gal was cheating on him 'in the pines,' and he killed her. He wants to hightail it out of town but doesn't have the money for transportation. The cold wind- or is it the memory? causes him to shiver.
Naow ain't thet more likely?