The Invention of Air

The Invention of Air: A story of science, faith, revolution, and the birth of America
Steven Johnson (2008, Riverhead)

“Here was a man at the very front lines of scientific achievement who was simultaneously a practicing minister and theologian--and who was, by the end of the 1770’s, well on his way to becoming one of the most politically charged figures of his time. He was an empiricist driven by a deep and abiding belief in God, who was simultaneously a revolutionary of the first order.”
I’m glad to be reminded of Joseph Priestly, whose career was interesting on many fronts, over and above his pioneering work with atmospheric gases. I would not have known, for example, that he was also among the fathers of Unitarianism, or that he counted among his friends not only Benjamin Franklin and James Watt, but John Adams and Thomas Jefferson . Steven Johnson’s The Invention of Air deftly weaves together all these strands in its portrayal of one of the last of the great polymaths.
Johnson’s book is not a comprehensive study of Priestly’s work: it’s just over two hundred pages long, which would be only a small fraction of Priestly’s own prodigious output of books, letters, and pamphlets. Rather, it sketches the connections between his scientific, political, and theological activities; “... for Priestly, these three domains were not separate compartments, but rather a kind of continuum, with new developments in each domain reinforcing and intensifying the others.”
In all three domains, he was both radical and principled. One of his principles was that information should flow freely: his discovery of a process to instill bubbles in liquids would make a fortune for his neighbor Johann Schweppes. More significantly, he shared his work on ‘dephlogisticated air’ with Antoine Lavoisier, who would soon turn the discovery the right way around, and name it oxygen. Lavoisier would go on to improve the French manufacture of gunpowder, which helped Priestly’s American friends succeed in their revolt against England. This, in turn, provided Priestly with a safe haven when his political and religious views made him dangerously unpopular at home in England. In 1791, a mob burned him out of his house and laboratory; he sailed for America in 1794, and lived there the rest of his life.
When Johnson digresses from the particulars of Priestly’s life, he has interesting things to say about the nature of scientific inquiry. On why Lavoisier was the one to complete Priestly’s discovery of oxygen: “Discovering that there was an air purer than pure air required the qualitative analytic skills--and improvisational style--that Priestly possessed in abundance. But defining the chemical composition of that air took a different toolkit, both mental and technological.”
He’s also interested in the way discovery takes place on various time scales. We tend to remember dramatic stories of ‘eureka’ moments, like Franklin with his kite--a story Priestly himself popularized in his pioneering history of electrical discoveries--but many hunches take years to play out, and one of Priestly’s most important discoveries had its roots in his boyhood, when he and his brother sealed up spiders in glass jars to see how long they would survive. As an adult, Priestly built more elaborate equipment to continue these studies. When he isolated a mint plant instead of an mouse, and was surprised to find that the air became more breathable rather than less, he took the first steps in a relay that we are still running today, in the continuing study of the interconnectedness of life, and the health or toxicity of the environment.
One result of the explosion of knowledge is that we don’t have thinkers today who are so influential in so many different spheres, but as Johnson points out, “[a]dopting a know-nothing attitude toward scientific understanding--to hide behind the cloak of piety or political dogma--would have been the gravest offense to Priestly and his disciples.” The attitude that all our progress has brought us to the brink of inevitable ruin is also one those great men would have shunned--can we do better? Let us try.
CTR

Published by email February 1, 2009
Thanks to Margo Risk for the loan of this book.