Cosmoline \Cos"mo*line\ (k?z"m?-l?n), n. [Prob. fr. cosmetic + L. oleum oil.] (Chem.) A substance obtained from the residues of the distillation of petroleum, essentially the same as vaseline, but of somewhat stiffer consistency, and consisting of a mixture of the higher paraffines; a kind of petroleum jelly.
The Military used this as a preservative. During and after WWII it seemed like everything came packed in cosmoline, or wrapped in cloth or paper soaked in cosmoline. The stuff has a very destinctive odor.
Smell is one of the most memory jogging senses. If you've ever smelled cosmoline you'll never forget it's aroma. I used to live on the docks of Valdeze, AK shortly after WWII, as a kid, and most fo the stuff was packed in that stuff. I swear when you'd open a pack of SPAM the stuff was packed in cosmoline.
Go down to your local Army Surplus store that has WWII and Korean War items and walk in the door... and you'll then know what gives the store the odor it has.
Removal of cosmoline is not easy. You can scrub, wash and rinse till you're blue in the face and it's faint odorific memory will still be on the item...
But.. hey, it works!