Does The Hobbit address the tension between dwarves and elves? If so, whose fault is the ancient feud between the dwarves and elves?

what was the

  this riddles' answer is library.

  the "leaves" are a reference to the books' pages that the library contains; the branches are a network of libraries that connect multiple libraries' collections, resources, and items in a system of a common database, integrating them; the branches' organization are a useful management tool for coordinating the multiple collections many libraries have.

the answer is the speaker views both as possessions that reflect his importance.  

following gollum to the back entrance