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Thomas Midgley Jr.

Thomas Midgley Jr. is a engineering topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Thomas Midgley Jr. rather than just read about it. In short: Thomas Midgley Jr. (May 18, 1889 – November 2, 1944) was an American mechanical and chemical engineer.

Thomas Midgley Jr. — main illustration
Thomas Midgley Jr. — illustration

Key takeaways

  • Thomas Midgley Jr. belongs to engineering; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Thomas Midgley Jr. to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Thomas Midgley Jr. from memory before moving on to harder problems.

Reference excerpt

Thomas Midgley Jr. (May 18, 1889 – November 2, 1944) was an American mechanical and chemical engineer. He played a major role in developing leaded gasoline (tetraethyl lead) and some of the first chlorofluorocarbons (CFCs), better known in the United States by the brand name Freon; both products were later banned from common use due to their harmful impact on human health and the environment. He was granted more than 100 patents over the course of his career. Midgley contracted polio in 1940 and was left disabled; in 1944, he was found strangled to death by a device he devised to allow him to get out of bed unassisted. It is often reported that he had been accidentally killed by his own invention, but his death was declared by the coroner to be a suicide. While the harmful effects of CFCs were not understood until decades after Midgley's death, tetraethyl lead was known to be acutely toxic by those involved in the development of leaded gasoline. This included Midgley, who publicly insisted that there was nonetheless no health hazard posed by the use of leaded gasoline in internal combustion engines.

Early life Thomas Midgley Jr. was born in Beaver Falls, Pennsylvania, on May 18, 1889, the son of Hattie Louise (née Emerson; 1865–1950) and Thomas Midgley Sr. (1840–1934). His family had a history of inventing; his father was an inventor in the field of automobile tires while his maternal grandfather, James Emerson, invented the inserted tooth saw. He grew up in Columbus, Ohio, and graduated from Cornell University in 1911 with a degree in mechanical engineering. Early on, Midgley had a penchant for finding useful applications for known substances. In high school, he used the chewed bark of slippery elm trees to give baseballs a more curved trajectory, a practice professional players would later pick up. Later in life, he was known to always carry a copy of the periodic table, his main tool in the search for the substance that would mark his breakthrough invention.

Career

Leaded gasoline

In 1916, Midgley began working at General Motors. In December 1921, while working under the direction of Charles Kettering at Dayton Research Laboratories, a subsidiary of General Motors, he discovered (after discarding tellurium due to the difficult-to-eradicate smell) that the addition of tetraethyllead (TEL) to gasoline prevented knocking in internal combustion engines. The company named the substance "Ethyl", avoiding all mention of lead in reports and advertising. Oil companies and automobile manufacturers (especially General Motors, which owned the patent jointly filed by Kettering and Midgley) promoted the TEL additive as an inexpensive alternative superior to ethanol or ethanol-blended fuels, on which they could make very little profit. In December 1922, the American Chemical Society awarded Midgley the 1923 Nichols Medal for the "Use of Anti-Knock Compounds in Motor Fuels". This was the first of several major awards he earned during his career. In 1923, Midgley took a long vacation in Miami to cure himself of lead poisoning. He said, "I find that my lungs have been affected and that it is necessary to drop all work and get a large supply of fresh air." That year, General Motors created the General Motors Chemical Company (GMCC) to supervise the production of TEL by the DuPont company. Kettering was elected as president with Midgley as vice president. However, after two deaths and several cases of lead poisoning at the TEL prototype plant in Dayton, Ohio, the staff at Dayton was said in 1924 to be "depressed to the point of considering giving up the whole tetraethyl lead program". Over the course of the next year, eight more people died at DuPont's plant in Deepwater, New Jersey. In 1924, dissatisfied with the speed of DuPont's TEL production using the "bromide process", General Motors and the Standard Oil Company of New Jersey (now known as ExxonMobil) created the Ethyl Gasoline Corporation to produce and market TEL. Ethyl Corporation built a new chemical plant using a high-temperature ethyl chloride process at the Bayway Refinery in New Jersey. However, within the first two months of its operation, the new plant was plagued by more cases of lead poisoning, hallucinations, insanity, and five deaths. The risks associated with exposure to lead have been known at least since the 2nd century BC, while efforts to limit lead's use date back to at least the 16th century. Midgley experienced lead poisoning himself, and was warned about the risk of lead poisoning from TEL as early as 1922. Midgley knew well the hazards of lead. He investigated whether the risks, both in production and use, could be managed. Testing on the exhaust was completed, which he used to support the idea that 1 part tetraethyl lead per 1300 of gasoline could safely be used. After the initial worker exposures, controls were developed to allow the process to operate safely. Leaded gasoline use grew exponentially. The cumulative chronic impacts of environmental lead were grossly underestimated. On October 30, 1924, Midgley participated in a press conference to demonstrate the apparent safety of TEL, in which he poured TEL over his hands, placed a bottle of the chemical under his nose, and inhaled its vapor for sixty seconds, declaring that he could do this every day without succumbing to any problems. However, the state of New Jersey ordered the Bayway plant to be closed a few days later, and Jersey Standard was forbidden to manufacture TEL again without state permission. Production was restarted in 1926 after intervention by the federal government; High-octane fuel, enabled by lead, was of military importance. Midgley later took a leave of absence from work after being diagnosed with lead poisoning. He was relieved of his position as vice president of GMCC in April 1925, reportedly due to his inexperience in organizational matters, but he remained an employee of General Motors.

… excerpt ends here. Continue reading the full article.

Illustrations

Thomas Midgley Jr. illustration
Thomas Midgley Jr.: Sign on an antique gasoline pump advertising the TEL anti-knock compound Ethyl, a gasoline additive
Sign on an antique gasoline pump advertising the TEL anti-knock compound Ethyl, a gasoline additive

Worked examples

Example 1 — a first encounter with Thomas Midgley Jr.

Start with the simplest possible case. Write down what Thomas Midgley Jr. claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Thomas Midgley Jr. before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Thomas Midgley Jr. ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Thomas Midgley Jr.

In research
Thomas Midgley Jr. appears in engineering research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Thomas Midgley Jr. in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Thomas Midgley Jr. is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1889 births, 1944 deaths, 20th-century American chemists, so understanding it makes those chapters shorter.
In everyday life
Look for Thomas Midgley Jr. outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Thomas Midgley Jr. in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Thomas Midgley Jr. means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Thomas Midgley Jr. out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Thomas Midgley Jr. in simple terms?

Thomas Midgley Jr. (May 18, 1889 – November 2, 1944) was an American mechanical and chemical engineer.

Why does Thomas Midgley Jr. matter?

Because it connects several engineering ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Thomas Midgley Jr.?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Thomas Midgley Jr..

Tags

  • 1889 births
  • 1944 deaths
  • 20th-century American chemists
  • 20th-century American engineers
  • 20th-century American inventors
  • Accidental deaths in Ohio
  • Air pollution
  • Cornell University College of Engineering alumni
  • Deaths by strangulation in the United States
  • Environmental controversies
  • Human impact on the environment
  • Inventors killed by their own invention

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