Daniel Fahrenheit was a major scientist of the 1700's. He was the the first man to create a stable thermometer using the metal mercury instead of alcohol and water. He created a system that has been used for approximately 300 years. The Fahrenheit system was once used all over Europe until England changed to Centigrade in the 1970's. He helped revolutionize medicine. Daniel Fahrenheit created the first system of measuring temperature ever.


Daniel Fahrenheit was born on May 14, 1686 with the name Gabriel Daniel Fahrenheit and "was one of one of Daniel and Concordia Schumann Fahrenheit's five children." ( His father was a wealthy banker living in Danzig Germany. On August fourteenth, 1701, when he was fifteen, both of his parents suddenly died on the same day. Some sources speculate that they were possibly poisoned using poisonous mushrooms. Fahrenheit was sent to become an apprentice to a shop keeper in Amsterdam, Netherlands.
While he was in Amsterdam he became very interested in the processes of making scientific instruments. After his four year apprentiship there, he traveled all over Europe studying how to make the scientific instruments He studied with various instrument makers in order to learn about all of the different things they could teach him. He took their ideas and used them to create his own instruments as well as improve on already established ideas.

His first Thermometer

After traveling abroad and becoming a member of the Royal Society, England's oldest scientific group, Fahrenheit decided to move back to the Netherlands. In 1701, Daniel Fahrenheit made his first thermometer. He used mercury instead of an alcohol and water mixture previously constructed by Gallileo and Guillaume Amontons. The alcohol and water mixture was very susceptible to atmospheric pressure and was highly inaccurate. However, Fahrenheit's new mercury thermometer was accurate because it was not susceptible to atmospheric conditions. Fahrenheit decided that his thermometer was useless without a measurement system to go with it so he set about trying to figure out the new system of measurement. In 1714, he created the first accurate mercury thermometer.

While studying abroad he also learned glass-blowing techniques. He used these to create the glass implements to create the first thermometers. He became quite skilled at this. Also, he learned how to clean mercury so that it would stick to the sides of the glass tube easier. Mercury, by itself is quite sticky but the process that he used made the mercury even stickier. This made it much more useful for his thermometer.

The Fahrenheit Scale

The scale we use today is actually Fahrenheit's third attempt at making a working scale. To create the Fahrenheit scale he chose a fixed high and low point. He then mixed salt and ice together. This was "then believed to be the coldest temperature achievable in the laboratory." ( It was then decided that the boiling point would 180 degrees different from the freezing temperature, which is the number of degrees in a semicircle. therefore, the freezing temperature of water would be 32 degrees and then, 180 degrees different at 212 degrees, would be the boiling temperature of water. To find out the average human body temperature, Fahrenheit took his wife's temperature with the thermometer and it registered ninety-six degrees. Later, scientists discovered that the temperature of the human body is actually 2.6 degrees hotter, registering 98.6 degrees.

The reason that Fahrenheit used mercury instead of alcohol was because mercury remains a liquid at room temperature. As the temperature rises the mercury will expand. If it is expanding against a measurement scale, then one will be able to see the change in temperature as it rises and lowers. However, because it does not change very much with day to day changes in temperature, it is relatively constant. This makes it easier to read large changes in temperature with the thermometer.

Other Accomplishments

Fahrenheit was also responsible for the invention of a new type of hydrometer, a tool used to measure the amount of humidity in the air. He also was involved with the invention of the thermobarometer. This was very important to finding out barometric pressure and also the temperature at which water boils. The thermobarometer has become more accurate and is now simply called the barometer. These inventions have evolved over the years to become beneficial in many ways to our modern society. We currently use them to help in forecasting weather.

After death

In 1742, six years after his death, Fahrenheit was posthumously awarded a full membership to the British Royal Society. He was elected to this position even after only publishing one scientific research paper. He was given this because of his extensive research into thermometers and his invention of the Fahrenheit system of measuring temperature. Later, after the Centigrade system was invented, the Fahrenheit system fell out of use with the scientists. This happened because the scientists felt that the other system was more accurate that the system that Daniel Fahrenheit devised. Now, in modern times more and more countries are switching to that system of temperature measurement for the same reason.


Daniel Fahrenheit's influence in science is still felt to this day. If you go to the doctor and they take your temperature, they most likely are using a mercury thermometer that uses the Fahrenheit Scale. When you hear the weather report on television or the radio, chances are they probably talk about the barometric pressure and whether or not you will be getting rain or snow. These two things were invented and perfected by Daniel Fahrenheit. He benefitted the world in many significant ways. Without him and his scientific exploration, we might all be using inaccurate alcohol thermometers. Also, Glenn "Hurricane" Schwartz would not be able to give us an accurate forecast for the upcoming snow this week!
The most interesting thing that I found out about Fahrenheit was that three hundred years ago he was able to imagine and invent something this important that we still use today. He had none of the resources that we have available to us today.

Daniel Gahrenheit
Daniel Gahrenheit