Lyric discussion by mtfujiinmypants 

Cover art for Masher lyrics by Mountain Goats, The

I'm thinking that the meaning has to do with senility or having a stroke. Brine boiling away could signify the evaporation of preservative fluids, spending time in jail, but not exactly could mean that he's trapped in his mind, and then losing control of language is often a symptom of stroke victims. It seems like too direct of a interpretation for the mountain goats, but that's what i take away from it.