The Invention of Air

I’ve just finished reading The Invention of Air, by Steven Johnson. He’s the one who wrote The Ghost Map. This is more good, old-school science, going back a couple hundred years to the life of Joseph Priestley. It’s pretty much a straight-up biography, but like Johnson’s other books, it’s a subject with threads reaching out into a lot of subjects.

Priestley’s name was familiar to me, but I don’t think I could have told you anything about him. He’s one of those Enlightenment-era polymaths. He was a theologian, scientist, and political philosopher. He co-founded the Unitarian church, invented seltzer water, and discovered oxygen. He uncovered the first evidence that would eventually drive the environmental movement nearly 200 years later. He was best buddies with Ben Franklin, an active ally of Jefferson’s, and nearly got thrown in prison by Adams. He was also a minister who published such heretical writings that his house was burned to the ground by an angry mob, which gets him a fair amount of street cred.

His most significant discovery, in the long run, was not specifically that of oxygen, but of the ecological cycle - that plants in some way made air breathable for animals. (At the time, there was a popular belief that trees somehow tainted the air, leading people to cut down any near their houses.) It was known that a candle placed in a sealed jar would snuff itself out, a mouse sealed in a jar would die, and that it would die faster if there were also a burning candle. (Yes, I feel bad for the poor little mice, too, but this was a different time.) So they knew there was something in air that mice needed to live and that candles needed to burn, and it was the same thing.

Priestley’s contribution was to extend this line of experiments to plants, and discover that they didn’t die. Not only that, but after a few weeks, the candle could be re-lit, and the mouse could survive, at least for a while. He shared his findings with Franklin, and they realized that this parlor trick had revealed the fundamental interdependence of life on earth. Centuries before the term “ecosystem” was introduced, they had glimpsed the underlying truth of the concept.

So how did a minister end up doing science, and how was he able to make such fundamental contributions to it? Interestingly, the answers to these questions also explain a lot about America’s revolutionary generation, because beyond any purely personal characteristics, Priestley embodied the spirit of his time. This was the Age of Enlightenment. There was an eagerness to look at the world anew, to question old explanations. Intrinsic in this was a willingness to challenge authority. This upheaval spread across all of the parts of his world: Science, religion, and politics. In all of these, new networks of people were emerging to challenge the old hierarchies. Without an intellectual establishment, there were few barriers between disciplines.

Alchemical theorizing, which had never worked very well, was finally overturned, and a new spirit of experimentation had taken over. The prosperity of the industrial age, however unevenly distributed, gave an army of amateur enthusiasts the time, education, and money to pursue and support science. With this went a new spirit of openness. Rather than being hoarded, scientific knowledge was published widely and discussed in coffee shops, drawing rooms, and society halls. Furious letter-writing formed an “Invisible College” of scientists throughout Europe. Priestley lived this principle more thoroughly than any man of his era, publishing early and often, providing step-by-step accounts of both successes and failures. It is certain that this allowed others to profit more from his discoveries than he did, but it’s unlikely that discretion would have gained him the same reputation and esteem. Much of that he owes to his voluminous correspondence with other scientists and documentation of his experiments. Within two years of meeting the members of the Royal Society, he had been inducted into it, and had published a 700-page book on electricity which became a standard university textbook. It’s clear that his passion was as much about sharing as discovery.

In Priestley’s time, scientific inquiry was still new. There were basic truths about electricity and chemistry, readily observable with simple instruments, which had never been investigated. There was much that he and others were able to learn just by observing the world around them, poking and prodding it, and asking lots of questions. He was able to make significant contributions to electrical theory within a year or so of setting up shop. Part of the appeal of his experiments lies in their physicality and accessibility. Some of his greatest discoveries came from experiments you could replicate in your kitchen sink. You don’t need a Large Hadron Collider.

His associates in his scientific research overlapped with a new force in politics, the industrial elites. These formed his network of ideas and support, both moral and financial. They were largely self-made men. Franklin had come from humble beginnings to build a printing business that gave him the money and leisure to pursue both science and public office. Priestley’s associates in Birmingham were the Lunar Men, led and funded by the newly-emerging captains of industry. They were rational enquirers, experimenters and tinkerers. Critically, the fortunes they had made were built on innovation - advances in steel, ceramics, steam power, and the industrial organization itself. And like America’s founding fathers, they were prosperous and powerful, but without a voice in the government. Their wealth was built on effort and creativity, not land, and land was the basis of political power in England. (Priestley, with his minister’s rhetorical flair, was inevitably drawn to support his friends and benefactors in this debate. He became an influential voice in public discourse, but that’s not what got him in Real Trouble.) This combination of education, wealth, and disenfranchisement was a potent cocktail on both sides of the Atlantic. This spirit of rational inquiry and empiricism is critical to understanding America’s revolutionaries. They weren’t just rich guys tired of paying taxes. They were driven more by a dissatisfaction with the established order, an enthusiasm for the new, and a willingness to risk and experiment.

Both of these groups also overlapped with the third, religious dissenters. The same spirit of open inquiry led many to question the established doctrines of the church, and to search for their own interpretation of scripture. Priestley, in his uniquely rational way, sought to strip away all of the layers of mysticism and superstition that had accreted to the church over the centuries. The end result was his publication of the alarmingly titled History of the Corruptions of Christianity, wherein he attacks commonly-held beliefs about the divinity of Jesus, the existence of the Holy Spirit, the holy communion, and the nature of the soul, to name a few. As with all of his writings on electricity and chemistry, it was sincerely meant to help the common man shake off the ignorance of received dogma. This is when the mob burned his house down.

There’s a lot of appeal and a surprising relevance to all of this. There’s a nostalgia for a time when science was something you could do on your own. (The closest we’ve come to this in recent years has been in software, with legends born in California garages.) We’ve also seen the revival of amateur enthusiasts of all stripes, and any number of innovative new ways of organizing communities and political groups. And it would probably do us a world of good if religion stopped thinking of science as its enemy.