[119. The electrical kite.]—But Franklin's greatest experiment was made one day in sober earnest with a kite. He believed that the electricity in the bottle, or Leyden Jar, was the same thing as the lightning we see in a thunder-storm. He knew well enough how to get an electric spark from the jar, for he had once killed a turkey with it for dinner; but how could he get a spark from a cloud in the sky?
He thought about it for a long time; then he made a kite out of a silk handkerchief, and fastened a sharp iron point to the upright stick of the kite. One day, when a thunder-storm was seen coming up, Franklin and his son went out to the fields. The kite was raised; then Franklin tied an iron key to the lower end of the string. After waiting some time, he saw the little hair-like threads of the string begin to stand up like the bristles of a brush. He felt certain that the electricity was coming down the string. He put his knuckle close to the key, and a spark flew out. Next, he took his Leyden Jar and collected the electricity in that. He had made two great discoveries, for he had found out that electricity and lightning are the same thing and he had also found how to fill his bottle directly from the clouds: that was something that no one had ever done before.
[120. Franklin invents the lightning-rod; Doctor Franklin.]—But Franklin did not stop at that. He said, If I can draw down electricity from the sky with a kite-string, I can draw it still better with a tall, sharp-pointed iron rod. He put up such a rod on his house in Philadelphia; it was the first lightning-rod in the world. Soon other people began to put them up: so this was another gift of his to the city which he loved. Every good lightning-rod which has since been erected to protect buildings has been a copy of that invented by Franklin.
People now began to talk, not only in this country but in Europe, about his electrical experiments and discoveries. The oldest college in Scotland[18] gave him a title of honor and called him Doctor—a word which means a learned man. From this time, Franklin the printer was no longer plain Mr. Franklin, but Dr. Franklin.
Dr. Franklin did not think that he had found out all that could be found out about electricity; he believed that he had simply made a beginning, and that other men would discover still greater things that could be done with it. Do you think he was mistaken about that?
18 The University of St. Andrews.
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FRANKLIN'S CANE
AND WASHINGTON'S REVOLUTIONARY SWORD. (Preserved in the Patent Office, Washington.) |
| FRANKLIN'S GRAVE IN CHRIST CHURCH BURIAL-GROUND, PHILADELPHIA. |
[121. Franklin in the Revolutionary War; Franklin and the map of the United States.]—When the war of the Revolution broke out, Dr. Franklin did a great work for his country. He did not fight battles like Washington, but he did something just as useful. First, he helped write the Declaration of Independence, by which we declared ourselves free from the rule of the king of England; next, he went to France to get aid for us. We were then too poor to pay our soldiers; he got the king of France to let us have money to give them.