Sentence:  We were forbidden to swing on the gates , lest they sag on their hinges in a poor-white-trash way , but we could stand on them , when they were latched , rest our chins on the top , and stare and stare , committing to memory , quite unintentionally , all the <WSD>details</WSD> that lay before our eyes . 
Meaning of the word marked with <WSD> tags:  a small part that can be considered separately from the whole