in America, expired with the sixth number. In 1742 he invented the stove of which he published a description in 1744 as An Account of the New Invented Pennsylvanian Fire Places. In 1743 he drew up proposals for an academy which eventually became the University of Pennsylvania, and in 1744 he founded the American Philosophical Society. In 1746 he witnessed Spence's electrical experiments in Boston, bought the apparatus, and repeated the experiments in Philadelphia, where interest in the new science was further stimulated that year by a present of a Leyden jar given to the Library Company by the English experimenter, Peter Collinson. To this English friend Franklin made extended reports of his earlier electrical investigations in the form of letters, which Collinson published in London in 1751 with the title "Experiments and Observations in Electricity, Made at Philadelphia in America, by Mr. Benjamin Franklin." In 1752 he showed the identity of lightning and electricity by his kite experiment, and invented the lightning rod. In 1748, being assured of a competency, he had turned over his business to his foreman, David Hall, and purposed devoting the rest of his life to philosophical enquiries. But he had inextricably involved himself in the affairs of his community, which, as soon as it found him at leisure, "laid hold" of him, as he says, for its own purposes—"every part of the civil government, and almost at the same time, imposing some duty upon me." He was made a justice
