d before 1747 his name probably
would not have descended to our times. He would have had only a local
reputation as a philanthropical, intelligent, and successful business
man, a printer by trade, who could both write and talk well, but was not
able to make a better speech on a public occasion than many others who
had no pretension to fame.

But a new career was opened to Franklin with the attainment of leisure
and independence,--the career of a scientific investigator. The subject
which most interested him was electricity, just then exciting great
interest in Europe. In 1746 he attended in Boston a lecture on
electricity by Dr. Spence, of Scotland, which induced him to make
experiments himself, the result of which was to demonstrate to his mind
the identity of the electrical current with lightning. What the new,
mysterious power was, of course he could not tell, nor could any one
else. All he knew was that sparks, under certain conditions, were
emitted from clothing, furs, amber, jet, glass, sealing-wax, and other
substances when excited by friction, and that the power thus producing
the electric sparks would repel and attract. That amber, when rubbed,
possesses the property of attracting and repelling light bodies was
known to Thales and Pliny, and subsequent philosophers discovered that
other substances also were capable of electrical excitation. In process
of time Otto Guericke added to these simple discoveries that of electric
light, still further established by Isaac Newton, with his glass globe.
A Dutch philosopher at Leyden, having observed that excited electrics
soon lost their electricity in the open air, especially when the air was
full of moisture, conceived the idea that the electricity of bodies
might be retained by surrounding them with bodies which did not conduct
it; and in 1745 the Leyden jar was invented, which led to the knowledge
that the force of electricity could be extended through an indefinite
circuit. The French savants conveyed the electric current through a
circuit of twelve thousand feet.

It belonged to Franklin, however, to raise the knowledge of electricity
to the dignity of a science. By a series of experiments, extending from
1747 to 1760, he established the fact that electricity is not created by
friction, but merely collected from its state of diffusion through other
matter to which it has been attracted. He showed further that all the
phenomena produced by electricity had their cou