'Then you would have us retreat to Minas Tirith, or Dol Amroth, or to Dunharrow, and there sit like children on sand-castles when the tide is flowing?' said Imrahil.
(RK 5.ix.878)
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How many of us have stopped to recognize how deftly Tolkien has suited this simile to its speaker? The subcreator is in the details.