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Let's start with some basic facts about the popular sport called "tenpin bowling". (Less popular are "candlepin" and "duckpin" bowling--and other variants--so we'll ignore those here.) Each tenpin weighs 3.5 pounds (my calculator computes that as about 1590 grams), and they are positioned in a triangular
pattern such the the center-to-center distance between any close pair of pins is 1 foot (30.48cm).
Meanwhile, bowling balls are about 8.5 inches in diameter (the official rules actually state that the circumference cannot exceed 27 inches, so divide that by pi to get 8.59-and-a-fraction inches). That's 21.59 to 21.83 centimeters in diameter (21.75, anyone?). The weight of a bowling ball ranges from 6 pounds to 16 pounds (2724 to 7264 grams of mass). While 16 pounds is the maximum
allowed weight, I think that lesser balls don't have to have weights that are exact pounds. That is, if you wanted a ball that weighed 12.3 pounds, somebody might be willing to make one, and so far as I know it would be legal. Also, I don't know that 6 pounds is the lower limit; I'm pretty sure I once encountered a kid who had a 5-pound ball. (There is a PRACTICAL lower limit, though, when you think about the fact that you want that lightweight ball to knock over a total of 35 pounds of tenpins!)
Finally, the bowling lane itself is 4 feet wide, and 60 feet from the "foul line" (don't cross the line or your score will be zero) to the first bowling pin. That's about 1.22 and 18.29 meters, respectively.
I think early versions of this sport predated the metric system, so that's why the internationally accepted measurements are in old-fashioned "English" units.
In the olden days of bowling, people called "pin chasers" had the job of manually setting up the pins at the far end of the bowling lane. Nowadays there are complicated automatic machines that do this job, and pin-chasers are mostly also mechanics, with the job of keeping the machines running. It is normal for a pin-setting machine to be stocked with 20 pins, so that while 10 are sitting on the lane, the other 10 can be in the process of getting moved to the part of the machine where it can set down the next batch of pins (the bowlers don't have to wait as long between fresh sets of pins).
For the purposes of the game of "pinning", we will stick with the 11 common ball-weights (from 6 to 16 pounds), and we will need one of each weight.
Note that bowling balls are almost always drilled with holes so that a person can easily grip a ball by inserting fingers into the holes. This has a side-effect of making a bowling ball no longer perfectly spherical; each hole can be considered somewhat equivalent to a "flat spot" on the surface of the ball. This is a Good Thing; we NEED at least one such flat spot on each bowling ball used for the game of "pinning".
Our complicated machine at the back of the lane will be loaded up with 11 bowling balls, as previously described. At random 10 of them will be set on the lane, "flat spots" down, in the same locations as is normal for tenpins. Since the balls are less than 9 inches in DIAMETER, they are less than 4.5 inches in radius, and the distance between two pin-spots is 1 foot, more than twice as much as 4.5 inches. The balls will fit just fine on the lane, without modifying anything except the machine (which needs humongous modifications, of course).
A standard tenpin has dimensions such that part of it, the "neck", is just about perfect for being gripped by the hand (no finger holes needed). The "pinner" grips the pin firmly, and approaches the foul line, and (underhand throw, like in bowling or softball) heaves the pin toward the triangular array of bowling balls, 60 feet away.
Since the flat spots on the balls are pretty small, it should not take a big impact to get a ball to start rolling. That's good, since the pin only weighs 3.5 pounds, and needs to shove as much as 16+15+14+...+7=115 pounds of balls off the lane...
You get two attempts, of course. If your first attempt misses the first ball in the triangular array, you will probably need your second try.
A good picture of the ten tenpins. [Vernon, Oct 10 2010]
Do pins dream of counting balls?
[2 fries shy of a happy meal, Oct 10 2010]
[pocmloc, Oct 10 2010]
[2 Fries]s Link
I got Aquatic Fauna from the link posted previously - not particularly relevant, but interesting! [pocmloc, Oct 10 2010]
||I've always spelled it with an "o". My dictionary spells it that way, also. Perhaps this is one of those English/American differences....
||Wow, talk about burying the lede. "A version of bowling in
which balls are substituted for pins and vice versa. The
balls are stationary at the end of the lane, and the pins are
rolled down the lane to knock over the balls." Is that
||Incidentally, as I
wrote the above, upon reaching the word "over" I realized
why bowling pins have the shape that they do: they have
two stable states: upright and lying on their side, the
latter of much lower energy than the former, and with a
fairly large energy barrier between. In lay terms, the
distinction between an upright pin, and one that's been
knocked over is very clear, with no gray-area between. For
a bowling ball with a small 'flat' on it, the distinction isn't
so clear. It has an infinite number of stable states,one of
very slightly lower energy than the others, and a fairly
small energy barrier between. In lay terms, a ball can be
knocked off its flat, and still remain in a state almost
indistinguishable from the set-up position.
||That's a problem this idea needs to solve. You need a
device or technique for making it obvious which balls have
been successfully dislodged.
||[mouseposture], the subtitle is what I choose to interpret as being the synopsis of this Idea.
||The back end of the lane, and the gutters at the sides, are for determining when a ball is no longer in play. Even ordinary tenpins sometimes slide sideways without falling over, and if they don't fall over and are still located on the lane, then they are still in play for the second attempt.
||In pinning, the law of conservation of momentum, plus the fact that the balls are fairly close to the end of the lane, should make it fairly easy for a dislodged ball to roll out of play.
||If not, well, that is why this Idea is Half-Baked. :)
||You aren't going to believe this [Vernon] but I drew a comic strip version of this like maybe twenty years ago now. [link]