Part 7 – 1748 to 1753 – Science, Publishing & The Mail Chapter 11 Father and Son Make History Benjamin Franklin and his twenty-one-year-old son were prepared on that hot and humid day in June of 1752. As huge thunderheads rolled over Philadelphia and most people took cover, William and his father hurried to the “commons”, the grazing grounds near their home at Race and Second Streets. Some of the things they needed for the experiment were already in a shed at the edge of the field. The rest, including a silk kite with a fifteen-inch metal wire attached to the top of its spine had been quickly gathered from the laboratory in their house. As the final preparations were made the sky darkened and a few heavy drops began to fall. The father took cover, actually he hid in the shed as the son ran with the kite. The elder Franklin, his reputation at stake, could not be seen running through a pasture with a child’s toy, nor did he want to be ridiculed if his bold experiment failed or disproved his theory. For four years his experiments with electricity had occupied nearly all his time. He moved to the house on Race Street to distance himself from friends and associates who were regularly interrupting his work. The relative isolation permitted the thought and experiments that produced significant contributions to the field. Among them was clarification of the models that described electrical phenomena by coining the terms “negative” and “positive” to describe electrical charges, replacing the much less descriptive, “viscous” and “resinous”. He was also first to use the terms battery, conductor and condenser and by storing the charge in a cloud in a simple capacitor called a Leyden Jar, he would test his most daring hypothesis; that lightning and electricity are the same thing. The wind became brisk as the storm front passed over. William launched the kite on the far side of the field and ran across it, playing out the string as he went. When he reached his father in the shed, he gave him the tether. Franklin tied the string and a strip of silk to a key. Holding the silk, which was an insulator, he then waited for the charge to build. He was now in a very dangerous position and he and his son both knew it. He had already killed animals with electricity and twice, by accident, he had knocked himself unconscious with it. On one occasion he had stunned and incapacitated six grown men with a sudden discharge and he’d seen drain spouts and sections of metallic roofs reduced to molten jelly. Now, by holding the kite string, Franklin was at the bottom of a likely path of a lightning stroke; a shaft of energy carrying millions of volts that heats the air around it to tens of thousands of degrees. As the kite danced about overhead he touched his knuckle to the key, hoping to feel a spark. There was nothing. He waited and with each second the likelihood father and son would become charred corpses increased but still the key carried no charge. Thunder rumbled and lightning flashed around them. William pointed out a huge cloud coming toward them. Thunder boomed from it as it passed directly over them. The little kite darted and dove in the gusts near the base of the cloud and again Benjamin Franklin touched the key. Still, there was nothing. His heart sank. His mind raced as he thought back on the hundreds of experiments he had conducted. Now he was trying to deduce why his theory, which seemed so clear in the laboratory, was incorrect. Then his