little leisure for anything else."

This was during the winter of 1746-7. Franklin suggested that the
electricity was collected, not created by friction. He also
propounded the theory of positive and negative electricity. He was, at
this time, comparatively a wealthy man, and consequently could afford
to devote his time to philosophical investigation. It is estimated
that his income, from his estates, amounted to about seven hundred
pounds a year; this was equal to about six or seven thousand dollars
at the present time. Mr. Parton writes,

"Besides this independence, Franklin was the holder of two
offices, worth together perhaps one hundred and fifty pounds
a year. His business, then more flourishing than ever,
produced an annual profit, as before computed, of two
thousand pounds; bringing up his income to the troublesome
and absurd amount of nearly three thousand pounds; three
times the revenue of a colonial governor."

Under these prosperous circumstances, Franklin withdrew from active
business, became a silent partner in the firm, and devoted nearly all
his time to the new science. He wrote, in the autumn of 1748, to his
friend Cadwallader Colden of New York,

"I have removed to a more quiet part of the town, where I am
settling my old accounts, and hope soon to be quite master
of my own time, and no longer, as the song has it, 'at every
one's call but my own.'

"Thus you see I am in a fair way of having no other tasks
than such as I shall like to give myself, and of enjoying
what I look upon as a great happiness, leisure to read,
study, make experiments, and converse at large with such
ingenious and worthy men, as are pleased to honor me with
their friendship or acquaintance, on such points as may
produce something for the common benefit of mankind,
uninterrupted by the cares and fatigues of business."

He wrote a treatise upon thundergusts, which displayed wonderful
sagacity, and which arrested the attention of nearly all the
philosophers in Europe and America. The all-important topics of this
exceedingly important document, were the power of points to draw off
electricity, and also the similarity of electricity and lightning. He
therefore urged that metallic rods might be attached to buildings and
ships, which, pushing their needle points above roofs and masts, might
draw the electric fire harmlessly from the cl