Petroleum-Based Lubricant

I’ve written songs about pancakes, chickens, dying on the toilet, and seagulls farting.  I think my strangest song topic is a petroleum-based lubricant.  Cosmoline is a brand-name lubricant that is often used by the military.  Initially, it is greasy like all other kinds of oil.  After some time it becomes waxy and impossible to remove without scraping and much cursing.  It’s great for keeping a military-issue jeep free of corrosion.  It’s also a great metaphor for the way our memories deteriorate over time.  A mental image is clear and slick at first and over time it becomes gummy, waxy, and a little bit crusty.