
When he reached the
age of forty, Franklin, in 1746, began his
electrical studies. We all know the story of his experiment with the
kite and key. But his work to determine the positive and negative
character of electricity, his improvements on the Leyden jar and his
invention of the lightning rod may not be so well known.
The lightning
rod is a good illustration of the direct thinking of Franklin's - which
was at odds with the prolific theorizing in those days. He expressed it
this way, "Utility is in my opinion the only test of value in matters
of invention."
By 1749, he wanted to devote his entire time to science but events in
this country changed his whole life. The threat of the French and
Indian alliance suggested a defensive measure to Franklin, and he drew
up a plan for the colonies to unite under a single government. But the
Colonial Assemblies turned it down on the basis that such a central
government would have too much power, and in England they thought the
idea entirely too democratic.
In less than 30 years however, the
Assemblies did adopt it. For this reason, Balzac credited Franklin with
inventing the idea of the United States.