BENJAMIN THOMPSON: BIOGRAPHY, CONTRIBUTIONS, ACKNOWLEDGMENTS - BIOGRAPHIES - 2024

Benjamin Thompson (1753-1814) was an American scientist and inventor famous for questioning Lavoisier's caloric theory in the 19th century. This held that an invisible fluid released heat into bodies.

Thompson discovered that the increase in temperature was a consequence of friction. He came across this finding when in a factory, drilling cannons, he observed that both the metal and the drill were heated during the procedure. Then, when he used water to cool the drill bit, the liquid boiled without the need to apply fire.

Portrait of Benjamin Thompson. Not specified

This finding was a great step for the development of thermodynamics. Although the process was very slow, there was intense debate and in the end it was found that thermal energy is simply molecular kinetic energy.

His career as an inventor began in the American War of Independence. Although he was an American, he contributed to the British of his own free will and there he became the major of a militia company.

In the war he designed a life preserver so that workhorses could cross the river without drowning and a carriage to carry cannons. He also delved into human nutrition research and made great social contributions.

Biography

Early years

He was born on March 26, 1753, in Woburn, Massachusetts. He attended a modest school, but occasionally escaped to Harvard College - a more prestigious institution - to listen to the lectures of Professor John Winthrop (political leader and first governor of Massachusetts).

As a young man, he worked as a shop assistant. But the owner of the place complained to Thompson's mother that Thompson placed more importance on reading science books and making machines than on customer service.

When he was 13 years old he became an apprentice to John Appleton, a lawyer and diplomat who was the first United States chargé d'affaires in Bolivia. This approach allowed Thompson to have contact with well-educated people.

He adopted some of the habits of those around him, there his interest in science grew more. However, he would switch from job to job without much success.

Role in the War of Independence

Benjamin Thompson's life took a significant turn in 1772 when he met a widowed woman and heiress with whom he fell in love. He married Sarah Rolfe, she had a great influence with the Governor of Portsmouth, New Hampshire and thanks to this he was appointed one of the commanders of the Militia.

When the American War of Independence began, Benjamin Thompson owned some land in New England and was against the uprising, so he activated troops to fight the royalists.

The popular party became his enemy because they considered him a traitor and in revenge a mob attacked his wife. Following these events, he fled to British lines and became an advisor to General Gage and Lord George Germain.

In 1785 he went to Bavaria, where he spent eleven years working for the army and in 1791 he received the title of Count of the Holy Roman Empire, thus adopting the name "Rumford".

Your personality

Thanks to some entries found in his diary, Benjamin Thompson can be described today as a very organized man. He would put everything in writing and stick to a schedule, every moment of the day was planned in advance.

In his notes it is found that, he established Mondays and Tuesdays for the study of anatomy, on Wednesdays he dedicated them to physics institutes, Thursdays to surgery, Fridays to chemistry with materia medica and Saturdays to physics. His eagerness for study allowed him to rub shoulders with people of different professions.

He also marked his activities by the hour, even noted the time to get up, wash his hands and breakfast.

Earl Rumford's death was sudden in August 1814. He left a will for his estate to be handed over as an inheritance to Harvard College. Today his grave is in a cemetery in Auteuil (France) and Harvard University is responsible for its maintenance.

Contributions and discoveries

A bust of Thompson in honor of his contributions. By No machine-readable author provided. Zerohund ~ commonswiki assumed (based on copyright claims). - No machine-readable source provided. Own work assumed (based on copyright claims)., CC BY 2.5, Benjamin Thompson is known to have conducted a large number of experiments throughout his life. With his friend from adolescence Loammi Baldwin (years later he became a prominent American politician and soldier) he created a scientific society to exchange problems and enigmas for several years.

He put a lot of effort into building a continuous motion machine, an electrical instrument similar to the Van de Graaf generator. He also conducted various studies on the strength of gunpowder explosions and thanks to these he was chosen to be part of the Royal Society.

- Contributions

The intensity with which he worked to prove his theories and create tools to improve people's lives paid off. These are some of his documented contributions:

Invisible Ink

On May 6, 1775, a letter from him crossed military lines in a context in which correspondence was being inspected. Benjamin Thompson sent a sheet of paper with important information from the war, but only about five lines were read.

The uniformed men did not take into account that it was a very large sheet for what it said there. On the rest of the page was a hidden message written in invisible ink made with gallotanical acid.

Vacuum food preparation

In 1799 Benjamin Thompson first mentioned the sous-vide method, which is nothing more than the preparation of food in a vacuum. His first experiment was with a pork shoulder.

Rumford Soup

It was a food made for soldiers with minimal cost, but with excellent nutritional capacity. It was prepared with potatoes, peas and cereals. Although it was devised for soldiers, it had a strong penetration in Europe and was served in public soup kitchens and charities.

- Discoveries

Many of his theories were incorrect, despite the fact that he used all the variables of the time and had great dedication to research. However, many of them were easily at a standstill. In any case, it did achieve important inventions that still have functionality today.

Convection currents

It was one of his most important discoveries. It is a way of transporting heat between two zones with different temperatures. For this there must be water or some other fluid for the evaporation process to take place.

In making this revelation, he made numerous experiments with all kinds of substances and, after studying each of the results, he published his theory which said that “any substance that tends to impede the movement of a fluid, be it a liquid or a gas, increases the insulating properties of the material ”.

Chimney improvements

Fireplaces were widely accepted in London and it was Benjamin Thompson who made a significant improvement to this invention. The new design added bricks to create a column of angled walls so that all the smoke circulated upward and no part was left in the room. In addition, it increased fire efficiency by controlling the rate of fuel consumption.

Industrial ovens

When Thompson improved the kilns used for the production of lime, they immediately began their manufacture throughout Europe. The correction was summarized to separate the burning of the fuel from the limestone, in this way, the ashes were not contaminated by the fire.

Thermal underwear

This American is credited with the invention of warm underwear. Thompson studied the thermal conductivity of fabrics for years in his quest to improve military clothing.

Light and photometry

From his discoveries with heat he went on to work on photometry or measurement of light. For this he built a photometer and used his own unit of luminous intensity.

Improved lamps

After working on photometry, Thompson wanted to put his discoveries into practice. He took some lamps invented by a Swiss named Ami Argand and perfected some of the processes to improve brightness and reduce the use of oil.

Filter coffee maker

Count Rumford liked comfort, good living and considered that the consumption of alcohol distorted that concept. Therefore, he looked for something that could replace it and concluded that only coffee was capable of doing it.

However, he had an obstacle. How to prepare it in a simple way? This is how he discovered that it should be done at a constant temperature and in a closed container so that it also retains all its flavor.

He found the solution to create what is known today as a filter coffee maker.

Publications

Some of the papers on his research were published, many of them taken directly from the citations he made in his journal. These are the most famous texts of the count:

Recognitions

- The Rumford lunar crater bears his name in memory of this inventor. It is one of the hidden faces of the moon.

- At Harvard University the chair of natural philosophy was named in his honor.

- Since 1800 the Royal Society has awarded the Rumford Medal every year, an award for outstanding scientific research related to the thermal or optimal properties of matter.

References

1. Sanbornc C. Brow (1965) Count Rumford.
2. E. Alexander Powell (1956) The Remarkable American Count.
3. Anales Real Academia Nacional de Medicina (2006) Volume CXXIII.
4. Frederick Bueche (1988) Physical Sciences.
5. Francis Weston Sears, Gerhard L. Salinger (1980) Thermodynamic kinetic theory and statistical thermodynamics.