Lyric discussion by nthn2 

Ok, here's the deal with Glycerine, it's volitale, if you leave it alone nothing happens, but shake it, and it'll blow-up in your face. Now, how does it relate to the song? The repeated theme "Don't let the days go by" and the sense that things were going wrong, but nothing was done about them is symbolic to just letting the glycerine sit, too afraid to shake it. But, things got to a point where the explosion was inevitable, and they were both badly scared when it went off. Now, looking back, he sees that that hurt could have been avoided if only something had been done earlier. This is only my view, and I want to read many others.

Sorry, but this is completely bogus. Glycerine/glycerol isn't remotely volatile, and it's certainly not explosive. It's even safe to eat for crying out loud. Two minutes spent on Wikipedia (specifically look at the NFPA ratings) would debunk this theory.

@dbbolton If you look at the date on the comment, Wikipedia had barely even been around for one year at that point. The commenter was most likely thinking of nitroglycerine and got confused.

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