Stealing God's Thunder

Most people think of Benjamin Franklin as a political leader who dabbled in science, but in his own day he was viewed, especially in Britain and France, as a distinguished scientist who acted as spokesman for his country. He would prove indispensable during the American Revolution as minister to France, where his personal renown made him a cult figure, and opened favorable access to Parisian opinion shapers.

In Stealing God's Thunder: Benjamin Franklin's Lightning Rod and the Invention of America, a gracefully written birth-to-death biography, Philip Dray covers many aspects of Franklin's activities, but concentrates on his scientific work, especially concerning electricity. The eighteenth century was fascinated by parlor tricks employing amber and the newly-invented Leyden jar. Franklin began treating such devices as toys, but then carried out careful experiments methodically exploring the phenomenon, using principles of scientific investigation he learned from Isaac Newton's Optics (1706).

Franklin theorized that electricity was a fluid that sought equilibrium; he coined the terms "negative" and "positive" to describe the flow, used the word "battery" for storage devices, and proved that lightning was an electrical discharge. Franklin described his findings in letters to English friends. Published as Experiments and Observations on Electricity (1751), the book received the Copley Medal of the Royal Society in 1753, and quickly went through five editions in English, three in French, one in Italian, and one in German.

Always interested in finding practical applications of his theories, Franklin invented the lightning rod. Widely adopted despite fears the rods might attract destructive lightning, his device earned the admiration of Enlightenment sages and the enmity of clergymen who could no longer claim severe storms were evidence of divine displeasure. The French economist Anne Robert Jacques Turgot celebrated Franklin's dual career with the phrase: "He snatched lightning from the sky and the scepter from tyrants."