On the last day of 1918 GM acquired Kettering’s various companies. Boss Kett turned up the heat on the anti-knock team, now working in an old converted residence on Ludlow Street: “By God, if you don’t come up with something within the next three to six months you’re all fired.”
Four long weeks later assistant Thomas Boyd stumbled upon aniline, which cut knock effectively. But it stunk so bad Midgley’s wife made him sleep in the basement. “I doubt if humanity, even to doubling their fuel economy, will put up with this smell,” he said. The lab spent months trying to make aniline bearable, then finally moved on. Boyd was sent off to investigate gas-alcohol options.
By the spring of 1921 with no breakthroughs, Midgley begged for a new assignment. Kettering was leaving on a business trip, and postponed his answer until his return. By chance he’d found a newspaper clipping about the element selenium. Sure enough, it reduced knock substantially. But the compound produced a terrible garlicky smell. Within days tellurium proved even more effective but just as smelly. The men toiled on.
By now they had tested as many as 33,000 compounds, by one estimate. Along the way, lab manager F.C. Clements noted that most coworkers had “given him very little encouragement."
But the growing clues began to hint at a solution. School chum Robert E. Wilson had just come up with a new version of the Periodic Table of Elements, arranged by how many electrons each atom had. In this arrangement the elements iodine, tellurium and selenium formed a clump that pointed toward lead. The hunt turned more scientific as Midgley and team tested compounds in the series. Then on December 9, 1921 assistant Carroll Hochwalt mixed up lead in an alcohol solution, tetra-ethyl lead (TEL). “Hell, it was eureka.”
A 1 part per 100 mix of tetra-ethyl lead in gasoline silenced engine knock. They cut the amount of TEL by half and it still worked. And then half that worked. In the end .025% of TEL in kerosene proved enough to solve engine knock, and Boss Kett began to smell success despite lingering problems. The leaded gasoline left engine deposits. But Kett ruled it was time to take the product to market and let customer feedback define the most crucial problems to fix. Otherwise they’d lose their shirt trying to perfect every aspect.
Kettering was a showman too. He took the tetra-ethyl lead additive and renamed it Ethyl. Ethyl was cute—a woman’s name that also implied ethyl alcohol, a long-tried additive to gasoline. And the name didn’t suggest lead at all.
A Dayton oil refinery started making batches of Ethyl and put it on sale February 1st, 1923. Soon customers learned their extra couple of cents per gallon were worth it. Cars stopped knocking themselves to pieces and gave much better horsepower. Word of mouth spread.
The use of lead also rang alarms in academia. In the days before the EPA and OSHA protected consumers and workers, safety was valued far less. Lead’s dangers had been known for centuries in industries like pottery. But Midgley’s lack of expertise in chemistry—the “intelligent ignorance” that Kettering valued—meant ignorance of hard-won lessons in safety too. The consequences would be fatal.
Lead poisoning occurs quietly. Signs don’t appear until high levels have built up in the body. In early 1923, after Midgley developed symptoms like tuberculosis and complained of “lead-lined lungs”, he took a six-week rest in Florida. Hochwalt went on a long honeymoon, also ill.
At the Dayton oil refinery producing the Ethyl fluid, greater ignorance and complacency prevailed—until 60 of the men were sickened and two died. Kettering blamed the men for not recognizing the danger. "We could not get this across to the boys."The cause of the deaths was kept secret, and to this day the victims’ identities are unknown—and are now shrouded by privacy laws. Midgley was despondent and considered quitting. But Kettering counseled this was the unavoidable price of progress.
Earlier in Florida, he had come to an astounding realization. Lead was cheap to mine. Ethyl was cheap to make. And a few drops of the additive justified a premium price for gas. The math showed a profit potential so enormous that within months General Motors and Standard Oil swiftly created the Ethyl Corporation, naming Kettering its president and Midgley vice president. Ethyl swiftly expanded nationwide.
While in Florida Midgley had written an oil industry executive, noting that tetra-ethyl lead stings and burns on contact with the skin, so that the poisoning of those handling the pure fluid would be “almost impossible.”
Then, as production shifted to east coast refineries, there came more fatalities. Five men died at a Standard Oil refinery, plus eight more at Du Pont, and this time their deaths were linked publicly to the Ethyl additive. Public outcry arose, and with it a knowledge gap. At a hasty press conference the ever-dramatic Midgley sought to prove consumer safety by washing his hands in what seemed to be the Ethyl fluid. ''I'm not taking any chance whatever... Nor would I take any chance doing that every day."
But was this the vastly diluted Ethyl-treated gasoline, or the pure, deadly additive? Meant to appear a Mr. Wizard, Midgley must have seemed more a Pontius Pilate to some. The worker deaths were put down to temporary development issues, and consumer safety was stressed, as the Ethyl gas contained such a vastly diluted amount of its mystery additive.
Kettering and Midgley lost their Ethyl positions, as the Surgeon General called a conference in 1925. Academic experts testified to the dangers, but industry representatives eventually outmaneuvered them.
Ethyl went back on the market a year later—five million dollars in the red, but with tightened refinery procedures and a strong marketing campaign. No more refinery deaths were reported. And soon consumers were buying gas from Ethyl and competitors like Gulf No-Nox for the added pep. New discoveries in the Middle East had put to rest fears of oil shortages for now.
Tetraethyl lead quickly became a standard component of gasoline in the United States. Britain’s petroleum secretary during WWII claimed the fuel helped win the aerial Battle of Britain against German planes. And during the decades it was on the market, its use saved a large percentage of the gasoline that might have been burned. But all that lead went somewhere. Industry had promised to study the long term effects, but it would take the work of a researcher in a totally unconnected field to find the answer.
While determining the age of the earth through radioactive decay of Plutonium, geochemist Clair Patterson discovered that atmospheric lead had shot up around 1923—right when Ethyl went on the market.
Patterson’s development of ultra-pure lab techniques and polar ice core work, combined with lead studies on children proved the connection by the early 1960s. After Ethyl was taken off market in the 1970s, blood levels dropped and child IQs rose. Lead toxicity remains an issue in poor areas, especially in places where lead exhaust accumulated over the decades and in the less regulated third world.
In 1928, Midgley’s final year living in Dayton, Kettering approached him with a new problem. The leading refrigeration company, Frigidaire, was part of GM, and boss Kett had decided they needed a new refrigerant. The existing chemicals were remarkably toxic and flammable, with many highly publicized deaths. Within months 100 would die in a Cleveland hospital.
Solving engine knock had taken five years; this problem took three days. Midgley knew the properties of an ideal refrigerant—nonflammable, non-toxic, stable and with a boiling point between 0 and -40C. At lunch he and two assistants studied a pocket-sized periodic table. Fluorine was perfect, except it was toxic. But what about one of its compounds?
"Plots of boiling points, hunts for data, corrections, slide rules, log paper, eraser dirt, pencil shavings, and all the rest of the paraphernalia that takes the place of tea leaves and crystal spheres in the life of the scientific clairvoyant, were brought into play," Midgley is quoted in the excellent Prometheans in the Lab. But soon “everything seemed right” as they realized they had uncovered a whole class of compounds that would be known as chlorofluorocarbons or CFCs. After Albert Henne prepared dichlorodifluoromethane, or R12, it performed perfectly. Too perfectly as it would turn out.
Next year the Midgleys moved to his hometown of Columbus where he built an estate and pursued his own research into synthetic rubber. He had turned down a GM vice presidency but remained a consultant, vice president at Ethyl and board member at Ethyl-Dow.
In 1930 he unveiled his refrigerant, dubbed “Freon,” with typical drama at the American Chemical Society. He lit a candle, boiled some Freon in a bowl then inhaled the vapor and blew out the candle. He had proved his new creation was nontoxic and inflammable at one stroke. And again put his health on the line to do so.
Safe refrigeration was a boon to mankind. People could bring in the icebox from the porch without worrying it might be lethal. Air conditioning, reduced food poisoning and refrigerated vaccines enabled better life worldwide for millions.
From 1922-1942 Midgley’s accomplishments were rewarded with chemistry’s four highest medals, the Nichols, Perkin, Priestley and Willard Gibbs Medals. He was elected president of the American Chemical Society, and enjoyed the comforts of wealth—a 50 acre estate, full wine cellar, golf and the freedom to pursue pure science.
All that came to an abrupt end in 1940 when within hours paralysis struck him from the waist down. The diagnosis was polio. He figured the odds for someone his age to contract the disease as "substantially equal to the chances of drawing a certain individual card from a stack of playing cards as high as the Empire State Building."
One can’t help wondering if his long-term exposure to lead along with the rest of the periodic table might not have contributed to his severe symptoms.
Ironically, Midgley received therapy at the Columbus Children’s Hospital, where young victims of lead poisoning were also treated. Despite some improvement he remained paralyzed from the waist down, and began clearing up his affairs. In his final presidential address he urged older chemists to step aside for younger minds, who historically have made the greatest advancements before age 45.