Did Ben Franklin really go fly a kite? Myth or not, scientists view his insights on electricity to be, uh, key. Tomorrow, the Franklin Institute celebrates.

Posted: June 16, 2006

On a cloudy June day in colonial Philadelphia, Benjamin Franklin stepped outside with a key, some twine, and a large silk handkerchief attached to "two cross-sticks of a proper length."

Thus began a little experiment that would become one of the most celebrated images in science.

Tomorrow the celebration continues when the Franklin Institute holds its annual commemoration of the inventor-statesman and his kite. This year it falls during the tercentenary of his birth.

Yet it is worth noting that there is some static in that kite image from June 1752, when Franklin drew down "electric fire" from the sky.

For one thing, he is lucky he didn't get electrocuted.

For another, the kite flight was of somewhat limited scientific importance.

And now a few historians doubt that it actually happened - any more than Galileo studied gravity by dropping balls from the Tower of Pisa.

None of this takes away from Franklin's importance in the early study of electricity, a realm so new and mysterious in the 18th century that live demonstrations were all the rage in the finest society parlors.

Insatiably curious yet lacking a college degree, Franklin described electrical concepts with terms we use today: battery, charge, positive and negative.

And he invented the lightning rod, correctly presuming that thunderbolts were simply a more dramatic version of the static electricity generated in those 18th-century parlor demonstrations.

When French researchers followed his instructions to make a lightning rod in May 1752 - a month before he is said to have flown his kite - Franklin became a scientific celebrity.

His kite experiment, if it happened, merely demonstrated once again that electricity could be drawn from above. Franklin had already published his theories on electricity, and he may have thought his kite was a mere afterthought.

Why, then, is that the enduring tale fed to U.S. schoolchildren?

"These iconic stories we like because they are simple and dramatic," said John Heilbron, a historian of science at the University of California, Berkeley.

Heilbron, who calls the kite experiment "a pretty damn fool thing to do," doesn't take a stand on whether it actually happened.

Tom Tucker, author of the 2003 book Bolt of Fate, has no doubt, describing it as yet another hoax by a notorious prankster. Among other oddities, he cites the fact that Franklin did not publicize the kite flight until four months later, and then only with a passing mention in the Pennsylvania Gazette.

A longer account, by Franklin's friend Joseph Priestley, did not appear until 15 years later.

Science historian David Rhees said the delay proved nothing, and he labeled Tucker's evidence "circumstantial."

Franklin took science seriously, said Rhees, formerly at the American Philosophical Society in Philadelphia and now executive director of the Bakken Library and Museum, a Minneapolis facility devoted solely to electricity.

"Although Franklin was a bit of a trickster, I doubt if he would play tricks with his colleagues in science," Rhees said.

"I don't think anybody can definitively say he did it or he didn't do it," said physicist Philip Hammer, vice president of the Franklin Center at the Franklin Institute.

In any event, there will be no kite-flying at the institute tomorrow, as an electrical charge can be drawn from the sky even when a storm is miles away.

Instead, museum staff will create artificial lightning in a controlled demonstration in the Stearns Auditorium. Children can also make their own kites and colonial hats.

In so doing, perhaps they will rediscover the sense of wonder that Franklin and his contemporaries felt as they explored the basic foundations of science.

They called themselves "natural philosophers," and very few, if any, pursued science as a profession. They seem like amateurs compared to today's university researchers, who work on large teams and must constantly apply for more grants.

The change hasn't all been for the good, said Alice Walters, who studies the history of science at Murray State University in Kentucky.

"I think one of the things that some modern science has lost is sort of this sense of play," Walters said.

Franklin, for example, came up with a rather playful way to demonstrate that dark colors absorb heat, she said. He laid squares of different-colored cloth in the snow, and observed that darker ones sank more quickly.

"You don't have institutions [today] that say, 'Go out and play and come back when you find something interesting,' " Walters said.

With electricity, Franklin was not alone in supposing that lightning was a form of it, said Philip Krider, professor of atmospheric physics at the University of Arizona.

A bigger contribution was his understanding that charges are conserved, Krider said, contrary to the popular idea at the time that charges could be "created" by rubbing items such as a glass rod.

Franklin saw electricity as a "single fluid," an excess of which caused a positive charge, and a deficit a negative one. Today we use the labels in reverse - the "fluid" is electrons, which we call negative.

But that doesn't diminish Franklin's success in seeing how the process worked, Krider said.

Initially dismissed as almost a New World bumpkin by old-guard natural philosophers in London, Franklin was quickly lauded as a man of science by the French.

And eventually, thanks to his electric fire, by the rest of the world.

Contact staff writer Tom Avril

at 215-854-2430 or tavril@phillynews.com.

comments powered by Disqus
|
|
|
|
|