Lyric discussion by thesithwithashotgun 

It does specifically mention mining, but this song always reminds me of the construction of the Transcontinental Railroad; when the railroad companies reached mountains, they blew tunnels through them in a manner similar to mining. Plus, for whatever reason, the violin, mandolin, and accordion riff reminds me of a train's whistle, further bringing to mind the railroad's construction.

Also, the chorus makes me think of a countdown to the explosion of the nitroglycerine. I'm not quite sure how to specifically interpret each line, but I think in its entirety the chorus is about the nitro.

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