After revolutionizing the auto industry with his electric self-starter, Kettering turned to another problem just beginning to cause worry. Cadillac engineers complained that Kettering's self-starter and battery ignition system was making spark plugs misfire, causing knocking in the cylinders.
But Kettering didn't think the plugs were misfiring. He suspected it was a problem with the fuel. As engines were designed to compress the fuel/air charge to a greater extent, engines were able to extract more power from the fuel. But the greater the compression, the greater the knock, Kettering found. The higher compression was causing the fuel to ignite before the spark. This pre-ignition was causing the knock.
The more efficient high-compression engines were necessary not only to make cars run faster, but because experts had determined in 1915 that the world's oil supply would be depleted by 1940.
Kettering assigned an assistant, Thomas Midgley Jr., to search for a compound to make the fuel less volatile, less likely to pre-ignite under compression, while retaining its high density of energy. Even though new discoveries of oil in Texas made it clear that the predictions of running out of oil were greatly exaggerated, Kettering and Midgley continued the search because higher-compression engines ran better and more smoothly, provided much more power and delivered greater fuel economy.
A number of chemical compounds were tried, including tellurium, which showed great promise for halting premature ignition, but smelled strongly of garlic. Its smell was so strong and it so completely defied all efforts to banish it that the researchers gave up and searched for something else.
In 1922, Midgley announced he had found it -- tetraethyl lead. It would eliminate premature ignition, he said, and could increase gasoline mileage by 25 percent.
The first ethyl gasoline went on sale in Dayton in early 1923. It was called "premium" gasoline. GM formed the General Motors Chemical Co., with Kettering as chairman and Midgley as president. It contracted to buy tetraethyl compound from DuPont.
GM then approached Standard Oil of New Jersey and the two companies formed Ethyl Gasoline Corp., which proved to be a very profitable venture. Until it all blew up in October, 1924.
An explosion in Standard Oil's research lab in Baywater, N.J., left 35 men seriously ill from inhaling fumes of tetraethyl lead. Eight were hospitalized and five of them died, one of them in a straightjacket because he had gone quite mad.
Newspapers headlined the effects of "looney gas" and a nationwide panic was started. New Jersey suspended sales of the compound and sales across the country collapsed.
Rumors circulated about poor devils who had gone crazy while motoring. This extremely important advance in automotive technology was in grave peril. In addition to being technologically important, it was extremely lucrative.
GM and Standard hesitated, hoping to ride out the storm of damaging publicity. Six more men died at DuPont's tetraethyl plant. GM and Standard ordered sales halted.
Scientists at Du Pont were well aware of the dangers in manufacturing tetraethyl lead, but they also knew it was perfectly safe in the greatly diluted form in which it appeared in gasoline (less than 1/10th of one percent by volume).
A federal committee appointed to investigate came to the same conclusion. Du Pont was willing to handle the risks and there was no danger to the public. A little over a year later, after an intensive advertising campaign, premium gasoline was back on the market.
Aiding in acceptance of ethyl was the popularity of the cars built by Walter Chrysler's new company, cars with high-compression engines.
One problem that GM had in its battle with Ford in the early '20s was that it was up against a myth, a legend, a national folk hero. Henry Ford himself was one of the most famous men in history. His attitude toward workers was suspect in many ways, but his $5 day had made him legendary. His peace ship venture had ended in failure and bickering, but his attempt had made him a hero. He had beaten the "vested interests" in breaking the Selden patent. And the Model T held an almost sacred position in the American mind.
But GM found a way to fight this: installment credit, a concept which was anathema to Henry Ford.
The automobile had quickly become not only a necessity to Americans, but also a status symbol. Pushed on by "easy-payment" credit, ownership of a car had become a symbol of success.
Installment buying spread to many product lines and was the driving force of the prosperity the '20s. Used-car dealers used easy-credit plans to clear their lots and to cut into sales of Ford's Model T, the most successful entry-level car ever built in America. The price of the Model T had dropped to as low as $265 in the mid-'20s. Ford's solution for all his woes to cut prices. But he refused to offer a time-payment plan and thereby contributed to his beloved Model T's decline.
But Ford's opposition to credit buying did not stop his greatest constituency, the farmers, from mortgaging their land to buy Model Ts and Fordson tractors. The auto industry had given the American farmer the means to an agricultural revolution from which everyone benefited but the farmer.
With modern farm machinery, farmers were able to increase their yields, thus driving down the price of their crops. At the same time, their own costs increased, because the new technology was not cheap. This paradoxical problem of increased efficiency undermining the prosperity of the farmer persists to this day.
The American farmer, aided by tractors, modern farm implements and new fertilizers and pesticides, became the wonder of the world. And low crop prices drove more of them off the farm and into the cities. The Great Depression started with the stock market crash in October, 1929. But a rural depression preceded it by several years.
By 1925, almost three-quarters of all automobiles sold in the United States were sold on credit. Still true.
Copyright 1996, Richard A. Wright
Published by Wayne State University's Department of Communications