Recreational mathematics

Dodgson was interested in puzzles and games throughout his life. This chapter concerns a wide range of recreational games and puzzles that he used to inform and entertain his child-friends and his colleagues. Among the topics included are problems involving time, probability, geometry, algebra, and arithmetic, and there are sections on calculating the days of the week, memorizing numbers, testing for divisibility, and on a wide range of other topics. Dodgson compiled puzzles for some of his young friends, and some of these were published in his lifetime (including some that he included in letters to magazines). Others were found in his papers after his death and published subsequently.