Lighting Rod

In 1749 Academy in Bordeaux in France offered the price this person who would prove the connection between electricity and lightning [!]. Benjamin Franklin from U.S.A., who was interested in a science lively, did not apply for the price nevertheless just according Franklin’s suggest Thomas Francois Railbird constructed an iron rod long about 12 m [1703 – 1779]. Determined guard Coiffier saw during coming storm [10th May 1752] how sparks long near 4cm jumping out from the rod. Even if it was a success and a support of Franklin’s idea, he himself was not satisfied, because it was not fulfilled his idea about ” sucking’ the lightning just from the storm clouds. And this way in 1752 Franklin set off a dragon in the clouds and he tied a metal key on the down end of the wet hemp string. During crossing the storm cloud he could see that free fibers become bristly and that they were repelling each other. When he drew near his ankle discharge happened, which was accompanied by jumping over a spark. The proof that the lightning is electrical character was given in an experimental way: The electric charge is in the lightning not in the thunder. Logic suggested him that if a lightning hits it will be better if it hits in a piece of iron than in his home. The first lightning rods were installed on buildings State House and Academy Building in Philadelphia. Confirming of Franklin’s theory flew round European intellectuals the same way like a news about the tragedy of George Wilhelm Richman from Estonia killed with lightning during experimentation with atmospheric electricity in 1753. This leaded to next experiments.

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Benjamin Franklin
(taken from  http://128.174.194.59/baym/255/portraits.htm)

Independently on Franklins experiments with atmospheric electricity a Czech natural historian, inventor and priest Prokop Divis. On their base he laid out the first ground lightning on 15th July 1754 in Primetice at Znojmo he tried to precede storms by sucking up electricity from clouds. His ” weather machine” was consisted from the wooden pole high 42 meters, which was covered with metal – plate. There were put several thousand of metal tips. The pole was stabilized with three chains, which were fastened to iron ground cones to ground. The lightning meant the first practical using of scientific knowledge about electricity.

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Prokop Divis

This idea started using but not without problems. The part of clergy was against using the lightning because the lightening was the express of The Lord’s angry. A French scientist came to conclusion that the lightning rod attracted lightning and so they did not save buildings but contrary they were danger for buildings. And that way in France the sure man was again put in front of administer justice for blasphemy because he made bold to provoke The Lord by laying the lightning. In The Great Britain the first public building saved with a lightning was cathedral of Saint Paul. It was in 1770. One year later the lightning was installed on the church of Saint Jacob’s in Hamburg.

The question, which was the first, is often discussed question. Divis or Frenklin? From the point of technical progress it is not important however.


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