" Above their heads by three feet was an opening in the roof. ‘A chimney,’ said Jimmy. ‘You climb up by putting your back to one side and feet to the other.’ ‘What if it widens too much?’ asked Laurie. ‘Then it’s usual to come back down. The rate of descent is up to you. I suggest you do it slowly. "

― Raymond E. Feist , Silverthorn (The Riftwar Saga, #3)