ssible to
make without lifting your pencil or going twice over the same line. Take
your pencil and see what is the best you can do.

241.--THE DISSECTED CIRCLE.

How many continuous strokes, without lifting your pencil from the paper,
do you require to draw the design shown in our illustration? Directly
you change the direction of your pencil it begins a new stroke. You may
go over the same line more than once if you like. It requires just a
little care, or you may find yourself beaten by one stroke.

[Illustration]

242.--THE TUBE INSPECTOR'S PUZZLE.

The man in our illustration is in a little dilemma. He has just been
appointed inspector of a certain system of tube railways, and it is his
duty to inspect regularly, within a stated period, all the company's
seventeen lines connecting twelve stations, as shown on the big poster
plan that he is contemplating. Now he wants to arrange his route so that
it shall take him over all the lines with as little travelling as
possible. He may begin where he likes and end where he likes. What is
his shortest route?

Could anything be simpler? But the reader will soon find that, however
he decides to proceed, the inspector must go over some of the lines more
than once. In other words, if we say that the stations are a mile apart,
he will have to travel more than seventeen miles to inspect every line.
There is the little difficulty. How far is he compelled to travel, and
which route do you recommend?

[Illustration]

243.--VISITING THE TOWNS.

[Illustration]

A traveller, starting from town No. 1, wishes to visit every one of the
towns once, and once only, going only by roads indicated by straight
lines. How many different routes are there from which he can select? Of
course, he must end his journey at No. 1, from which he started, and
must take no notice of cross roads, but go straight from town to town.
This is an absurdly easy puzzle, if you go the right way to work.

244.--THE FIFTEEN TURNINGS.

Here is another queer travelling puzzle, the solution of which calls for
ingenuity. In this case the traveller starts from the black town and
wishes to go as far as possible while making only fifteen turnings and
never going along the same road twice. The towns are supposed to be a
mile apart. Supposing, for example, that he went straight to A, then
straight to B, then to C, D, E, and F, you will then find that he has
travelled thirty-seven miles in five turnings. N