THE CANTERBURY PUZZLES
and two diagonals), whether you turn the diagram upside down or
not
?
You must not use a 3, 4 or 5, as these figures will not
reverse, but a 6 may become a 9 when reversed, a 9 a 6, a 7 a 2,
and a 2 a 7. The 1, 8 and 0 will read the same both ways.
Remember that the constant must not be changed by the reversal.
103.—
The Tube Railway.
The above diagram is the plan of an underground railway. The
fare is uniform for any distance, so long as you do not go twice
along any portion of the line during the same journey. Now
a certain passenger,
with plenty of time on
his hands, goes daily
from A to F. How
many different routes
are there from which
he may select ? For
example, he can take the short direct route, A> B, C, D, E, F,
in a straight line ; or he can go one of the long routes, such as
A, B, D, C, B, C, E, D, E, F. It will be noted that he has optional
lines between certain stations, and his selections of these lead to varia-
tions of the complete route. Many readers will find it a very
perplexing little problem, though its conditions are so simple.
104.
The Skipper and the Sea-Serpent.
Mr. Simon Softleigh had spent most of his life between Tooting
Bee and Fenchurch Street. His knowledge of the sea was there-
fore very limited. So, as he was taking a holiday on the south
coast, he thought this was a splendid opportunity for picking up a
little useful information. He therefore proceeded to " draw" the
natives.
" I suppose/' said Mr. Softleigh one morning to a jovial, weather-
beaten skipper, " you have seen many wonderful sights on the rolling
seas ?
" Bless you, sir, yes," said the skipper. " PVaps you've never
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