can be made, as we have seen, out of the chessboard and the peculiar
moves of the chess pieces. I will now give just a few examples of
puzzles with playing cards and dominoes, and also go out of doors and
consider one or two little posers in the cricket field, at the football
match, and the horse race and motor-car race.


378.--DOMINOES IN PROGRESSION.

[Illustration]

It will be seen that I have played six dominoes, in the illustration, in
accordance with the ordinary rules of the game, 4 against 4, 1 against
1, and so on, and yet the sum of the spots on the successive dominoes,
4, 5, 6, 7, 8, 9, are in arithmetical progression; that is, the numbers
taken in order have a common difference of 1. In how many different ways
may we play six dominoes, from an ordinary box of twenty-eight, so that
the numbers on them may lie in arithmetical progression? We must always
play from left to right, and numbers in decreasing arithmetical
progression (such as 9, 8, 7, 6, 5, 4) are not admissible.


379.--THE FIVE DOMINOES.

[Illustration]

Here is a new little puzzle that is not difficult, but will probably be
found entertaining by my readers. It will be seen that the five dominoes
are so arranged in proper sequence (that is, with 1 against 1, 2 against
2, and so on), that the total number of pips on the two end dominoes is