He began to experiment at the age of eleven, when he selected spiders and insects and placed them in bottles to ascertain how long they could live without fresh air. A few years later he made “electrifying machines,” and a kite of fine silk, six feet wide, which he could take apart and carry in his pocket. The string was composed of thirty-six threads and a wire, similar to that used by Dr. Franklin, in Philadelphia, to “bring electric fire from the clouds.” At nineteen, Priestley was sent to Daventry, where he embraced the heterodox side of almost every question, as he afterwards wrote of his three years at Daventry: “In my time the academy was in a state peculiarly favorable to the serious pursuits of truth, and the students were about equally divided upon every question of much importance, such as ‘Liberty and Necessity,’ the ‘Sleep of the Soul’ and all the articles of theological orthodoxy and heresy.” After leaving Daventry, he preached for three years to a dissenting congregation at Needham. In 1761 he was a professor at Warrington Academy. While here he published several of his books and made such experiments in electricity and “fixed air,” that the results began to be noised abroad. He married, while at Warrington, a daughter of a wealthy iron manufacturer, a Mr. Wilkinson. In one of his visits to London he met Benjamin Franklin. He became a member of a famous club which met at the London Coffee House, and here he interested Franklin in his experiments, and they became the closest friends. Both became members of the Royal Society and both in turn received its highest honor, the Copley medal. Each obtained from Edinburgh University the degree LL. D. Oxford conferred a like degree upon Franklin, while for a space of a century it ignored his heretical friend. In 1860 a statue of Dr. Priestley was erected at Oxford by Prince Albert, afterward King Edward. Franklin wrote to Priestley, in 1777: “I rejoice to hear of your continual progress in those useful discoveries. I find you have set all the philosophers of Europe at work upon fixed air (carbonic acid gas); and it is with great pleasure I observe how high you stand in their opinion, for I enjoy my friend’s fame as my own.” When Franklin was in France during the closing days of the Revolution, Priestley was there pursuing literary work. He was afterward made a citizen and offered a seat in the National Assembly. Shortly before the American Revolution, Priestley wrote anonymously three pamphlets in defense of the colonies. His influence was potent. Dr. Priestley announced his discovery of “dephlogisticated air” (oxygen) in 1774, to a large assemblage of philosophers who were dining at the house of M. Lavoisier in Paris. This was man’s first introduction to the mighty element that makes one-fifth of the atmosphere in volume and eight-ninths of the ocean by weight, besides forming one-half of the earth’s solid crust and supporting all fire and all life.