to H, H to I,
and so on, is one furlong in length. It will be seen that there are
thirty-one of these passages. Now, an official has to inspect all of
them, and he descends by the shaft to the point A. How far must he
travel, and what route do you recommend? The reader may at first say,
"As there are thirty-one passages, each a furlong in length, he will
have to travel just thirty-one furlongs." But this is assuming that he
need never go along a passage more than once, which is not the case.
Take your pencil and try to find the shortest route. You will soon
discover that there is room for considerable judgment. In fact, it is a
perplexing puzzle.

[Illustration]

248.--THE CYCLISTS' TOUR.

Two cyclists were consulting a road map in preparation for a little tour
together. The circles represent towns, and all the good roads are
represented by lines. They are starting from the town with a star, and
must complete their tour at E. But before arriving there they want to
visit every other town once, and only once. That is the difficulty. Mr.
Spicer said, "I am certain we can find a way of doing it;" but Mr. Maggs
replied, "No way, I'm sure." Now, which of them was correct? Take your
pencil and see if you can find any way of doing it. Of course you must
keep to the roads indicated.

[Illustration]

249.--THE SAILOR'S PUZZLE.

The sailor depicted in the illustration stated that he had since his
boyhood been engaged in trading with a small vessel among some twenty
little islands in the Pacific. He supplied the rough chart of which I
have given a copy, and explained that the lines from island to island
represented the only routes that he ever adopted. He always started from
island A at the beginning of the season, and then visited every island
once, and once only, finishing up his tour at the starting-point A. But
he always put off his visit to C as long as possible, for trade reasons
that I need not enter into. The puzzle is to discover his exact route,
and this can be done with certainty. Take your pencil and, starting at
A, try to trace it out. If you write down the islands in the order in
which you visit them--thus, for example, A, I, O, L, G, etc.--you can at
once see if you have visited an island twice or omitted any. Of course,
the crossings of the lines must be ignored--that is, you must continue
your route direct, and you are not allowed to switch off at a crossing
and proceed in another direction. There is no