"Give my love to Rose" - what killed him?

Those of you who know the song “Give my love to Rose” by Johnny Cash, know that it’s about a man (the narrator) who finds another man dying by the railroad tracks. The dying man asks the narrator to visit his wife and child and give them the money he’s saved.
Listening to it for the umptieth time today, I realized that the narrator never states what the man was dying of. Logically, the most obvious things could be eliminated:

  1. He wasn’t mugged/robbed and left for dead. He still has the “bag of money”, which his assailants certainly would have taken with them.

  2. He could have been freezing and/or starving to death, but again, the fact that he has money suggests that he might have found a place to stay.

So what is it? Does anyone have an idea? A rumour? An educated guess? This isn’t exactly keeping me up at night, but I’d like to hear your thoughts.

Hit by a train?

Hehe. I thought about that one briefly, too. But don’t train drivers tend to notice something like that, despite the size of their vehicles? If so, I doubt they would just move on and leave him bleeding to death.

It’s not all that difficult to get hit by a train without making yourself noticed. If you’re hit head-on or if you get yourself under a wheel it would be hard to keep it a secret but if you were alongside the train and got knocked in the head by some hangy-offie part you might not be noticed- likewise if you were lying down between the tracks, most of the train cleared you just fine, you didn’t disrupt the wheels, but you got hit by one of the hangy-downie parts.

Anyway, it doesn’t really matter what kills the guy. If the guy wasn’t dying there’d be no story. So, basically, the reason he’s dying is because he has to be dying in order for there to be a story. Relate this to Dogster’s article about the MacGuffin and let me know if you agree that his explanation applies here.

I always figgered it was wounds from a knife fight in a nearby bar that killed Rose’s guy.

No reason for the above, just kinda’ works for me.