Circle Puzzles 97- THE THREE FENCES
"A man had a circular field," said Crackham, "and he wished to divide it
into four equal parts by three fences, each of the same length. How might
this be done?"
"Why did he want them of the same length?" asked Dora.
"That is not recorded," replied the Colonel, "nor are we told why he wished
to divide the field into four parts, nor whether the fence was of wood or iron,
nor whether the field was pasture or arable. I cannot even tell you the man's
name, or the color of his hair. You will find that these points are not essen-
tial to the puzzle."
- SQUARING THE CIRCLE
The problem of squaring the circle
depends on finding the ratio of the
diameter to the circumference. This
cannot be found in numbers with
exactitude, but we can get it near
enough for all practical purposes.
It is equally impossible, by Euclid-
ean geometry, to draw a straight line
equal to the circumference of a given
circle. You can roll a penny carefully
on its edge along a straight line on a
sheet of paper and get a pretty exact
result, but such a thing as a circular
garden bed cannot be so rolled.
The line shown, when straightened
out, is very nearly the exact length ofthe circumference of the accompany-
ing circle. The horizontal part of the
line is half the circumference. Could
you have found it by a simple method,
using only pencil, compasses, and
ruler?- THE CIRCLING CAR
The outside wheels of a car, running on a circular track, are going twice as
fast as the inside ones.
What is the length of the circumference described by the outer wheels? The
wheels are five feet apart on the two axles.