I just purchased one of the "Wonderful Barrel" puzzles mentioned in
Stan Isaac's note, and I found the enclosed set of instructions to be
a classic. I figured I'd pass them on, in case some of the members of
this list don't buy the puzzle itself. The first couple of paragraphs
are not so great, but it gets better toward the end.

@begin(verbatim)
"Wonderful Barrel" is a kind of mental game plate also can be regarded
as an indoor ornament. The red, orange, yellow, green, blue, black
color balls which is inner in barrel can create more than 10 billion
combination to reach a solution and finally be aligned on 5 straight
lines, yet each straight line are with 4 same color balls.

* PLAY RULE *

Original alignment circumstances is as follow: there are three black
balls are set on SHELTER but each black ball is above a shore of
PLUNGER; the 5 straight lines are up the SHELTER with different color
from one another, each line contains 4 same color balls. The 5
straight lines are aligned in clock-wise with blue, green, yellow,
orange, red color.

As you know, the original alignment is orderly, now you can
circumvolve DRUM, then operate plunger up and down for taking the ball
out from SHELTER. While you put the ball into SHELTER again, the
order of "each straight line with 4 same color ball" has been broken
to confused state.

Now, a challenge is ahead of you, you often successful in this line
but irregularly in that line, in a word, it always can not come to a
satisfactory arrangement of the whole lines fluently.

At the beginning, it is not easy to arrange the 5 straight lines
return to initial order in short time, so please try to solve this
puzzle from one line first, then completion of two, three, four even
to whole lines are returned to initial order finally.

At last, maybe you can analyse the mystery out, but maybe you can not
solve it today; however, how about tomorrow? one month later? one
year later? or ten years later you may still continued to challenge to
it singlely and unwilling.
@end(verbatim)

P.S. I @i(tried) to proofread this, but as you can see, it was difficult.
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