DANIEL GABRIEL FAHRENHEIT: BIOGRAPHY, CONTRIBUTIONS, WORKS - BIOGRAPHIES - 2024

Daniel Gabriel Fahrenheit (1686-1736) was an important German-born physicist and instrument maker. Its main contribution had to do with the creation of the first thermometers, which allowed us to have a more precise instrument at the beginning of the 18th century. He also stood out for having established in 1724 a more effective temperature scale that bears his name. That scale even today remains in force.

Fahrenheit spent much of his life in the Netherlands as a physicist and engineer, although he did not work as a glassblower either. His interest in science was what motivated him to study and learn more about the physics of things. Although this was not normal for those who made instruments, Fahrenheit's contributions led him to join the Royal Society.

Representation of Daniel Fahrenheit. Source:, via Wikimedia Commons.

Today the Fahrenheit scale is still used in some parts of the world. The best known place is the United States.

Biography

Daniel Gabriel Fahrenheit was born on May 24, 1686. He was born in Danzig, an area that was part of Germany, but is now considered Gdansk, a city in what is now Poland.

The physicist's parents were Daniel and Concordia Fahrenheit. The couple died when Daniel was only 15 years old and it was due to the ingestion of poisonous mushrooms.

Although Daniel and Concordia had 10 children, only five reached adulthood. Of these five brothers Daniel Gabriel was the oldest. After the death of his parents Fahrenheit began training to become a merchant in Holland. His other four siblings were placed in foster homes.

Obviously he received the name Daniel from his father and Gabriel from his great-grandfather on his mother's side.

There are some discrepancies regarding the date of your birth. Some sources claim that he was born on May 14. The problem was due to the fact that at that time England was governed by a different calendar than the one used in Gdansk.

The English used the Julian calendar until 1752, while in Poland the Gregorian reform was accepted from 1582.

Studies

Fahrenheit moved to Amsterdam in 1708 to apprentice to a merchant who taught him accounting. It was there that he first met the Florentine thermometer; This thermometer was an instrument that was created in Italy almost 60 years earlier, in 1654, by the Duke of Tuscany.

During this stage he decided to visit Ole Christensen Rømer, a Danish astronomer whom he was able to observe in the graduation process of some thermometers.

This event piqued the curiosity of Fahrenheit, who decided to start making thermometers for a living. The decision had some consequences. The German had to put aside his apprenticeship as an accountant and the Dutch authorities issued arrest warrants against him.

Due to this situation, Fahrenheit spent several years traveling all over Europe and meeting with different scientists.

After several years he was able to return to Amsterdam and stayed in Holland for the rest of his professional and personal life.

Invention of the thermometer

Although thermometers already existed, none of these instruments were very accurate at that time. Two thermometers never showed the same temperature even though they measured the same phenomenon.

This was because the type of liquid to be used in thermometers was not universally defined. Nor had a scale been established that was universal.

The manufacturers of Florentine thermometers, for example, marked the lowest scale of their thermometers for the coldest day in Florence. For its part, the hottest day served to establish the highest value on the scale.

This procedure was an error, because the temperatures varied over the years, so there were no two thermometers with similar temperatures.

This problem affected Fahrenheit's work for several years, until he made an alcohol thermometer that was more accurate. This happened in the year 1709; Then his experiments evolved until he reached the mercury thermometer, also known as silver, which was born in 1714.

These thermometers also used the Fahrenheit scale to express temperature. Until the change of the scale to Celsius, Fahrenheit was widely used in Europe, although it is still used in the United States for daily measurements, as well as in territories such as Puerto Rico or Belize.

The process he used to make his thermometers was not made public for the first 18 years. It was considered a trade secret.

First appliance

The first thermometers Fahrenheit made had a column of alcohol inside them. This alcohol expanded and contracted due to the temperatures. The design was in charge of the Danish astronomer Ole Christensen Rømer in the year 1708; a design that Fahrenheit supervised in detail.

Rømer used alcohol (which was really wine) as a liquid and set two benchmarks. He selected 60 degrees as the temperature of the boiling water and 7.5 degrees as the temperature needed to melt the ice.

Fahrenheit devised another temperature scale for his alcohol thermometers that consisted of three points.

Thanks to the fact that these devices showed a high level of consistency between them, something that had not happened previously, Christian Wolf dedicated an entire article to the invention in one of the most important magazines of the time. All by analyzing two thermometers that had been delivered to him in 1714.

Importance of mercury

As time went by, Fahrenheit decided to substitute the alcohol in its thermometers to use mercury. The reason was because the expansion rate of mercury turned out to be more constant than that of alcohol and therefore mercury could be used to measure broader ranges of temperatures.

Fahrenheit then came to a conclusion that Isaac Newton had already reached in the past. He understood that it was more accurate to base the thermometer measurements on substances that change their temperature constantly and not on more or less hot days.

These advances contradicted the ideas established for the time. Some scientists believed that mercury could not be used in thermometers because it had a low coefficient of expansion.

Fahrenheit scale

Over time he refined the scale that was used to measure temperatures. The first step was to eliminate body temperature as a fixed point on thermometers. The scale was brought to the freezing and boiling water points.

It was learned how Fahrenheit established the values ​​of his scale thanks to an article he published in 1724.

Fahrenheit explained that the lowest temperature was achieved by making a refrigeration mixture consisting of ice, water, and ammonium chloride (which is nothing more than a salt). When this mixture stabilized, a thermometer was used until the liquid marked the lowest possible point. That reading that was obtained was taken as the zero degree on the Fahrenheit scale.

The second benchmark was achieved when a reading was obtained on a thermometer that had been placed in water and with ice only present on the surface.

The last benchmark, 96 degrees, was obtained by placing the thermometer under the arm or in the mouth.

This scale underwent some modifications when Fahrenheit died. 213 degrees were taken as a reference for the boiling point of water and 98.6 degrees were the reference for the value that the human body should have, displacing the 96 degrees that had been established in the past.

This scale is the one that is still used in the United States today, as well as in some English-speaking countries.

Contributions to science

In addition to the relevance that Fahrenheit had in developing more effective thermometers and establishing a more effective scale, the physicist also had other contributions to science. For example, he was the first person to show that the boiling point of liquid elements can vary according to atmospheric pressure.

Fahrenheit suggested that this principle be used when building barometric devices.

Another of his contributions has to do with the creation of an instrument that served to pump liquids. It was especially important for draining some low ground in Holland.

He also created a hygrometer, which was an instrument that was used to measure humidity.

These contributions show that his point was strong in his role as producer. In addition, the cash from their inventions made were forced to seek new tools to solve scientific problems that were appearing with the passage of time.

For this reason, he worked on being able to measure the expansion of glass, on evaluating the behavior of mercury and alcohol as temperature meters. Also he studied the effects of atmospheric pressure and succeeded in establishing some substances densities.

His contributions were not much or very noisy beyond the Fahrenheit scale and thermometers, but he was important in the course that experimental physics took in the 18th century.

Published works

His bibliographic contribution was not very extensive. The same year that he was admitted to the Royal Society he wrote his only manuscripts. In total there were five articles of small extent, which were written in Latin and published in the journal The Philosophical Transactions.

Death

Fahrenheit's death happened very early. The physicist died in The Hague, Holland, on September 16, 1736 when he was only 50 years old. His burial took place in the same city of his death.

No marriage was known to him and he remained professionally active until the last days of his life. Few details are known about the causes of his death. It has been claimed that it was due to mercury poisoning, as a result of all his experiments and works.

References

1. Coates, E. The temperature scales of Fahrenheit and Celsius.
2. Lin, Y. (2012). Fahrenheit, Celsius, and their temperature scales. New York: PowerKids Press.
3. Oakes, E. (2001). Encyclopedia of world scientists. New York: Facts on File.
4. Merriam-Webster Inc. (1991). The Merriam-Webster new book of word histories. Springfield, Mass.
5. Zitzewitz, P. (2011). The handy physics answer book. Detroit: Visible Ink.