Physics Takes a Holiday

My family made a lot of cross-country trips when I was growing up, either to visit relatives or to move. When we came across roadside attractions -- rattlesnake farms, caged bears, crocodile pools etc. -- my brother and I longed to stop but knew it was hopeless.

My parents were generally fun to travel with, but they were pretty frugal and considered such diversions a waste of time and money. And since time was money, they figured they saved double by sailing past the lurid signs, usually with disparagement on their lips.

Particularly disfavored were the sites marked with huge question mark signs that promised a supernatural experience in which the laws of gravity would be bent or broken, and objects or even people might be larger or smaller than they appeared. "Gyp joints," said my mom, nobody's fool.

Now I'm a big boy and occasionally stop the car at such places, including the ones with sideways gravity. I'm never disappointed, maybe because mom taught me to expect so little.

But it's a special treat to have learned that in vacation destinations like Puerto Vallarta, the kinds of places I never got to as a kid, you often find people who are willing to dispense you your amazement up front and hope you'll be kind enough to pay afterward.

This rock stacker is a perfect example. The vast Bahia de Banderas (Bay of Flags) has coughed up millions of stones. The streets here are paved with them, and there were plenty left over.

This man's genius appears to be that he can see at least one axis of equilibrium running through each of them, and the exact spots on top and bottom where the stone can rest on a companion below or support one above.

His wife watches the tip box, into which I slid a 20 peso note before I took my pictures. We watched for a while, and it looked like hard work. There's no sleight of hand involved. But even if there were, the stacks would be eye-catching. Each one seems to have required a different set of skills, and they're as unique as snowflakes.

I think mom and dad were wrong not to let us have a look at a few of those ? places. Questioning laws of nature is good for our brains, even if most of us aren't Einstein and won't ever understand the fine print.

And anyone who thinks it's silly to believe there might be such a thing as sideways gravity is forgetting that the gravity that pulls straight down as we all take for granted was an unplumbed mystery to Einstein and, unless I missed a headline, remains so to this day.