father of fizz

In honor of "Pepsipocalypse," and my own inordinate fondness for Diet Coke (which I share with Bora!, as evidenced by the photo at the end of this post, although he's partial to the sugared variety), it seems appropriate to pay tribute to the grand-daddy of fizzy drinks: British scientist Joseph Priestley. He didn't actually invent carbonation, which is a natural process: at high pressures underground, spring water can absorb carbon dioxide and become "effervescent." "Seltzer" originally referred to the mineral water naturally produced in springs near a German town called Niederseltsers, although today, it's pretty much just filtered tap water that's been artificially carbonated. No, Priestley is responsible for the artificial carbonation process, along with "discovering" oxygen (more on that, and the caveats, later) and eight other gases, including carbon dioxide and nitrous oxide (laughing gas).

Born in 1733 in a small town near Leeds, Priestley was the eldest of six children born to Jonas Priestley, a "dresser and finisher of cloth," and Mary, the daughter of a local farmer. So fecund was his mother, that the brood grew rapidly, and Joseph was sent to live with his grandfather at an early age. His mother died when he was nine, and when his father remarried, he was adopted by his father's sister. In her household, he was exposed to the theological and political discussions of so-called "Dissenters," a group of believers who did not strictly adhere to the doctrines of the official Church of England, and were often discriminated against, if not outright persecuted, for their supposedly heretical beliefs. He was extremely precocious, mastering (via recitation) his catechism by age 4 (!). (Overachiever. Sheesh. I could barely read at 4.)

Initially Priestley attended local schools, but a bout with tuberculosis in his teenage years forced him to drop out. He had learned Greek, Latin and a bit of Hebrew while at school, and subsequently taught himself French, Italian, German, Chaldean, Syrian and Arabic), as well as the basics of geometry and algebra. He enrolled at Daventry Academy with the aim of becoming a minister, and it was here he first became interested in what was then known as natural and experimental philosophy. But he became a minister, nonetheless, despite suffering from a speech impediment (the result of his childhood illness) and alienating some members of his first rural congregation in Needham Market, Suffolk, with his strong Unitarian leanings. He was much happier in his second post at Nantwich, Cheshire, where he helped establish a school and trained his students in natural philosophy, among other subjects.

Technically, Priestley was a Rational Dissenter: one who "emphasized the rational analysis of the natural world and the Bible," according to Wikipedia. He loathed strict dogma and eschewed mysticism. Priestley was probably relieved when, in 1761, he was transferred to the far more urbane Warrington (known as "the Athens of North") to become a tutor of modern languages and rhetoric at the local Dissenting Academy. He married in 1762 -- to one Mary Wilkinson, whom he described as "a woman of excellent understanding much improved by reading, of great fortitude and strength of mind, and of a temper in the highest degree affectionate and generous; feeling strongly for others, and little for herself" -- and became acquainted with scientific society during annual visits to London.

Warrington was an excellent environment for Priestley's growing interest in scientific experimentation. He met Benjamin Franklin in London, who encouraged him to investigate electricity. Priestley initially focused on reproducing known experiments, but soon found himself designing his own experiments to answer some of the questions raised. He published A History and Present State of Electricity, and was elected a fellow of the Royal Society in 1766 as a result of this work. He even published a popularized version of the book, teaching himself perspective drawing so he could illustrate the concepts adequately. His description of "a current of real air" between two electrified points" would later influence both Michael Faraday and James Clerk Maxwell in their pioneering studies of electromagnetism. But his interests soon turned to chemistry.

By 1767, Priestley was living next to a brewery in Leeds and started experimenting with the brewery gas (carbon dioxide) using candles and burning pieces of wood. In one such experiment, he placed a bowl of water above the surface of a liquor in the process of fermenting, and found it quickly took on a sweetly acidic taste akin to the famed mineral water of Niederseltsers. The end result was the 1772 publication of Impregnating Water with Fixed Air, which included very simple instructions:

"If water be only in contact with fixed air, it will begin to imbibe it, but the mixture is greatly accelerated by agitation, which is continually bringing fresh particles of air and water into contact. All that is necessary, therefore, to make this process expeditious and effectual, is first to procure a sufficient quantity of this fixed air, and then to contrive a method by which the air and water may be strongly agitated in the same vessel, without any danger of admitting the common air to them; and this is easily done by first filling any vessel with water, and introducing the fixed air to it, while it stands inverted in another vessel of water."

The Royal Society awarded him the prestigious Copley Medal for his work in carbonation. Priestley's carbonation process was further refined, and bottled "seltzer water" officially hit the commercial market in 1807, thanks to a Yale University chemistry professor named Benjamin Silliman. The first soda fountain appeared in Philadelphia in 1838, featuring sweetened and flavored carbonated drinks, and by 1891 there were more soda fountains in New York City than bars. Just a few years earlier, in 1886, Atlanta druggist John S. Pemberton sought a remedy for headaches and hangovers, and devised the bright idea of adding kola nut extract to coca extract. The result: Coca-Cola. A century later, the diet version of Pemberton's concoction would get me through many a college all-nighter, and remains the pause that refreshes even today. Thank you, Mr. Pemberton. 

And then he discovered oxygen -- or, more precisely, he became the first to isolate "dephlogisticated air," along with seven other kinds of gases. (Both Carl Scheele and Antoine Lavoisier also can stake a claim to oxygen's discovery.) This was a huge achievement. Remember that Priestley was working in a pre-modern chemistry environment,  at a time when most scientists still adhered to the principles of Aristotle -- namely that there was only one kind of "air." This was also an era dominated by the so-called "phlogiston theory," in which burning or oxidizing a given substance corresponded to the release of another material substance. It was used to explain things like combustion, smelting, calcination and similar chemical processes.

Basically, he isolated oxygen in its gaseous state by using a pneumatic trough apparatus (see illustration) for "gathering gases over water," or in Priestley's early experiments, mercury.

In an experiment conducted in August 1, 1774, he focused sunlight through a lens, thereby heating a sample of mercuric oxide, resulting in a gas that allowed a candle to burn brightly, and also enabled a mouse to live for a good long while under glass. "I have discovered an air five or six times as good as common air," he wrote. Over the next 12 years, he compiled Experiments and Observations on Different Kinds of Air, replacing Aristotle's outdated theory of four elements with Priestley's own variation of phlogiston theory. He called his discovery "dephlogisticated air." (Priestley was surprisingly frank when writing about his experiments, both successes and failures. One of his early biographers noted, "Whatever he knows or thinks, he tells: doubts, perplexities, blunders are set down with the most refreshing candour.")

While traveling in Paris later that year, Priestley met Lavoisier and replicated his experiment for the French chemist. It was Lavoisier who figured out that what Priestley had really discovered was purified air ("without alteration"), leading to the abandonment of phlogiston theory by the scientific community. Instead, the new chemistry embraced the concepts of elements and compounds, and the notion of conservation of mass (mass is neither created nor destroyed in chemical reactions). Unfortunately, for whatever reason, Priestley rejected the Lavoisier school of thought, insisting that there were only three types of "air": "fixed," "alkaline" and "acid." He rejected conservation of mass, and still insisted on focusing on "changes in the sensible properties" of gases, and even though he successfully isolated carbon monoxide, he never realized it was a different kind of "air. So he never embraced the modern chemistry for which his work paved the way. French naturalist George Cuvier, writing in the 19th century with the benefit of hindsight, lamented Priestley's uncharacteristic stubbornness in clinging to the phylogiston theory, describing him as "the father of modern chemistry [who] never acknowledged his daughter."

Priestley's religious convictions cost him dearly, both personally and professionally. While serving as a minister in Birmingham, he earned considerable public enmity for some of his pamphlets, particularly those attacking the doctrine of the Holy Trinity. He was branded an agent of the devil and denounced in the House of Commons. Technically, being a dissenter and disagreeing with the Church of England meant you could be stripped of of the rights of citizenship, and members of the sect were routinely persecuted. Small wonder that when the French Revolution broke out across the English Channel, dissenters tended to side with the revolutionaries and against privileged tyranny, having suffered at the hands of a state-sponsored religion.

On July 14, 1791, there was a dinner at a local hotel to celebrate Bastille Day, which went off peacefully enough, despite a large crowd gathered outside in protest. The violence came later that night, after said crowd had been drinking heavily: they sacked and burned both meeting houses where Priestley preached, even though he hadn't even attended the dinner. Warned that a mob was after him, Priestley fled the house with his family, "with nothing more than the clothes we happened to have on." He suffered the sight of his home going up in flames, destroying his laboratory and many unpublished manuscripts. The riot raged for three whole days, and many other homes were destroyed.

The family fled to London, but the hostility followed them. Poor Priestley was burned in effigy, once again denounced in the House of Commons, as well as from Church of England pulpits, and was even forced to resign his membership in the Royal Society by scientific colleagues (who one would think should have been more tolerant of dissenting views). On the upside, France made him an honorary citizen, although since France was then at war with England, this didn't help Priestley's standing back home.

Realizing he would never have peace again, Priestley and his family emigrated to America in 1794, when he was 61. He was offered a chair in chemistry at the University of Pennsylvania, but opted instead to follow his elder son, Joseph, and a friend, Thomas Cooper, 150 miles north of the City of Brotherly Love, in the town of Northumberland. It was intended to be a colony for English dissenters, but within a year Priestley's youngest son had died. Priestley kept up with his experiments in a brand new laboratory, but found himself spending winters in Philadelphia to stave off the isolation. He also founded the first Unitarian church in the US, and both John Adams and Thomas Jefferson attended his sermons.

Unfortunately, Priestley's physical health wasn't as robust as his mind. He nearly died in 1801 during a trip to Philadelphia (Jefferson by then was US President), and never fully recovered. By February 1804, he could no longer shave or dress himself, and was bedridden. There's a touching account of his death here. Apparently, after bidding farewell to his children, he reviewed some manuscripts he'd been working on with the help of Thomas Cooper, finally nodding and saying, "That is right. I have now done." He died 30 minutes later, mindful of his family to the end: he put his hand to his face as he expired so his wife and son wouldn't see it happen.

For all the animosity Priestley faced as a result of his religious beliefs, by the time he died he was among the world's most respected scientists, and a member of almost every scientific society in the Western World. (No doubt it helped that he spoke so many different languages.) In 1833, on the 100th anniversary of Priestley's birth, Michael Faraday -- arguably an intellectual descendant of this reluctant father of modern chemistry --  praised his forebear's "freedom of mind" and "independence of dogma and of preconceived notions, by which men are so often bowed down and carried forward from fallacy to fallacy." Faraday exhorted his listeners to follow Priestley's example, fostering "a mind which could be easily moved from what it had held to the reception of new thoughts and notions." That, indeed, is the mark of an excellent scientist.

This blog post brought to you by Coke (TM) and Diet Coke (TM). And, indirectly, Joseph Priestley.

Comments

[Chris Clarke]

One of the most refreshing posts I've read in a long time.

[Diandra Leslie-Pelecky]

Ahhh... now it comes out. The SciBlogs thing wasn't about ethics. It was a blatant Pepsi/Coke thing...

Seriously, there is an interesting story about Mr. Lavoisier: After Lavoisier was executed during the French revolution, she gathered together all of his notes and publications (which had been confiscated) and published his memoirs. She had been an important assistant in his work and made some contributions to the field of chemistry. She married Count Rumford (another scientist), but they had a horrible four-year marriage before divorcing, with Rumford making some comment to the effect of, "having lived with Mrs. Lavoisier, perhaps Mr. Lavoisier was the one with a more fortunate ending", suggesting that beheading was preferable to living with Marie Anne.

Nothing like some good physics gossip to get the day going. I have a craving for a soda now.

[Simplicio]

Was early beer not carbonated? It seems like it would be hard to avoid, and looking at the wiki article for sparkling wine it looks like using fermentation to purposely carbonate wine was understood at least by ~1650 by a Christopher Merret.

So I'm calling shenanigans on Preistly being the first to induce artificial carbonation, though he may have been the first to do so to water.

[Vatine]

Simplicio: Early beer was more commonly of an "ale" type, fermented in open (or only covered) vats, with the produced carbon dioxide mostly diffusing out through the liquid out into the brewery. So early beer was (mostly) flat.

Lager-style beer is brewed in a pressurized environment, with the pressure being provided by the carbon dioxide given off by the yeast. Lager-style beers are pretty modern, as these things go.

Also, do not (necessarily) look at what comes out of the taps at the pub, most pubs will be using either nitrogen or carbon dioxide to provide pressure in the kegs. This then squirts the beer to the tap and into a waiting glass.

[Berfrois]

[...] Salzer not salsa! [...]

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