| Experiments and observations on electricity made at Philadelphia in America | |
| 1751 |  |
| Benjamin Franklin(1706-1790) | |
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Benjamin Franklin, eminent as one of the founders of the United States who participated in drafting the Declaration of Independence and the Continental Congress Ambassador to France, was better known in Europe as a natural scientist at that time because of his studies on electricity. Franklin became the first American scientist to develop an international reputation. This book is a rare, complete set of Franklin’s reports on his electrical experiments. The first pamphlet contains Franklin’s experiments, and analysis of the Lyden jar in which he accumulated static electricity and his single fluid theory of electricity derived from these studies. Franklin thought that electricity was a kind of non-materialistic fluid, which filled up every body. If the body were filled with his fluid in excess, it changed to a “plus” charge, and if the fluid were deficient, the body held a “minus” charge. In the progress of this study, Franklin coined and introduced at least 25 fundamental electrical terms which include “plus”, “minus”, “positive”, and “negative”. This “fluid” theory was partially correct and was accepted widely until Faraday developed a new theory. In his later pamphlets, Franklin presented his investigations on lightning. He recognized the similarity between the electric spark in the Lyden jar and lightning, and proved this through his famous kite experiment in 1752. In this experiment he fastened metal cotters with silk string to a kite, and flew it in a thunderstorm. In the midst of the lightning, the silk string was charged by the atmospheric electricity, and then sparked as his finger touched the cotter and finally charged the Lyden jar connected to it. Franklin consequently invented the lightning rod from this dangerous experiment in 1753 and it rapidly spread throughout the United States. Through this research, Franklin not only developed the theoretical study of electricity, but also opened up the field of applied electricity, what is now known as electrical engineering. |
