THE CANTERBURY PUZZLES
architect, " I did not tell thee that the window must be square, as it
is most certain it never could be."
37.—
The Crescent and the Cross.
" By the toes of St. Moden," exclaimed Sir Hugh de Fortibus
when this puzzle was brought up, " my poor wit hath never shaped
a more cunning artifice or any more bewitching to look upon. It
came to me as in a vision and ofttimes have I marvelled at the thing,
seeing its exceed-
ing difficulty. My
masters and kins-
men, it is done in
this wise."
The worthy
knight then pointed
out that the cres-
cent was of a par-
ticular and some-
what irregular
form, the two distances
a
to
b
and c to
d
being straight lines, and
the arcs
a c
and
b d
being precisely similar. He showed that if
the cuts be made as in figure 1, the four pieces will fit together
and form a perfect square as shown in figure 2, if we there only
regard the three curved lines. By now making the straight cuts
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