Sentence:  I fancied at first the stuff was paraffin wax, and smashed the jar accordingly. But the odor of camphor was unmistakable. It struck me as singularly odd, that among the universal <WSD>decay</WSD>, this volatile substance had chanced to survive, perhaps through many thousand years. 
Meaning of the word marked with <WSD> tags:  The process or result of being gradually decomposed.