Kite Experiment led to Lightning Conductor

Benjamin Franklin (1706-1790) pictured in US $ 100 Bill was a famous politician and a scientist. It is in 1752, he conducted an experiment in connection with electricity charged clouds. He flew a homemade Kite during a thunderstorm. The Kite was made of a silk cloth mounted on a wooden cross. About one foot of iron wire was protruding above the kite. A key was tied to the end of metal string connected with the kite and the other end of the key was tied to a silken ribbon which Benjamin held while flying the kite.

A bolt of light struck the kite wire and travelled down to the ky causing a Spark. This proved that lightning is electricity and large electricity charged clouds can be brought to earth. There was time when high rise buildings were destroyed quite frequently by lightning. Benjamin Franklin invented lightning rod for the safety of building from lightning of cloud.

The device is called lightning arrestor. The lightning conductor is a long metal rod with its upper end pointed. It is fixed on the roof of the building and its lower end is put into the earth. When an electricity charged cloud passes over the tall building its charge is absorbed by the rod and relayed into earth through the metal rod and thus the building is protected from lightning.

After 1753, many lightning conductors were made in USA. They were then called Frankin rods. In 1760, Edstone light house was protected by such a rod.