According to legend, June 15 is the day Ben Franklin flew his kite during a thunderstorm in the field near Philadelphia, thereby proving something important about electricity.
In fact, we’re not sure this is the actual date. We’re not even certain that Ben ever conducted this famous experiment. (The account was written by someone else years later.) And Franklin’s experiment proved nothing that most scientists of his age didn’t already know. Franklin’s genius was discovering a way to prove what people believed: Electricity was the same thing as lightning and not composed of dual elements.
He proved this point by flying a kite in an electrical storm and observing static electricity travelling down the wet kite string to make the strands of twine stand on end. He knew enough to protect himself from electrocution by insulating himself from the wet kite string.
Most us know something about Franklin’s airborne tests of electrical theory. Few are aware of another kite-based experiment he performed years before. Here is his account.
“You will not be displeased if I conclude these hasty remarks by informing you, that as the ordinary method of swimming is reduced to the act of rowing with the arms and legs, and is consequently a laborious and fatiguing operation when the space of water to be crossed is considerable; there is a method in which a swimmer may pass to great distances with much facility, by means of a sail. This discovery I fortunately made by accident, and in the following manner.
“When I was a boy I amused myself one day with flying a paper kite; and approaching the bank of pond, which was near a mile broad, I tied the string to a stake, and the kite ascended to a very considerable height above the pond while I was swimming. In a little time, being desirous of amusing myself with my kite, and enjoying at the same time the pleasure of swimming, I returned; and loosening from the stake the string with the little stick which was fastened to it, went again into the water, where I found, that, laying on my back and holding the stick in my hands, I was drawn along the surface of the water in a very agreeable manner. … I began to cross the pond with my kite, which carried me quite over without the least fatigue, and with the greatest pleasure imaginable. I was only obliged occasionally to halt a little in my course, and resist its progress, when it appeared that, by following too quick, I lowered the kite too much; by doing which occasionally I made it rise again. I have never since that time practiced this singular mode of swimming, though I think it is not impossible to cross in this manner from Dover to Calais. The packet-boat, however, is still preferable.”
Readers who have spent time along America’s coasts will, no doubt, recognize the modern version of Franklin’s discovery—kite surfing.