Timeline of temperature and pressure measurement technology Facts for Kids

This is a look at the exciting history of how people learned to measure temperature (how hot or cold something is) and pressure (the force pushing on something). These inventions help us understand the world around us, from checking our body temperature to predicting the weather!

Early Steps in Measuring Heat and Pressure
See also

Early Steps in Measuring Heat and Pressure

The 1500s: Seeing Heat Change

1592–1593 — The famous scientist Galileo Galilei built one of the first devices to show changes in heat. It was called a thermoscope. It worked by using air that would expand when hot and shrink when cold, moving water up or down a tube.

The 1600s: New Tools and Ideas

1612 — Santorio Sanctorius made the very first thermometer designed for doctors to use.
1617 — Giuseppe Biancani published a clear drawing of a thermoscope, helping others understand how it worked.
1624 — The word "thermometer" first appeared in a French book. It described a device with an 8-degree scale.
1629 — Joseph Solomon Delmedigo wrote about a sealed-glass thermometer that used brandy inside. It was quite accurate for its time!
1638 — Robert Fludd created a thermoscope that had a scale, making it a true thermometer.
1643 — Evangelista Torricelli invented the mercury barometer. This amazing tool could measure air pressure, which is super important for weather forecasting.
1654 — Ferdinando II de' Medici, Grand Duke of Tuscany, made the first modern-style thermometers. They were sealed glass tubes filled with alcohol and worked by the liquid expanding when it got warmer, not by air pressure.
1669 — Honoré Fabri suggested a temperature scale. He divided the difference between the "greatest heat of summer" and melting snow into 8 equal parts.
1676 to 1679 — Edme Mariotte did experiments that led to using the temperature of deep cellars as a fixed point for measuring temperature. This was a more stable reference than melting snow or freezing water.
1685 — Giovanni Alfonso Borelli wrote a book that shared an interesting discovery: the temperature of blood inside an animal was the same in different parts of its body.
1688 — Joachim Dalencé suggested making a thermometer by dividing the space between freezing water and melting butter into 20 equal degrees.
1695 — Guillaume Amontons made important improvements to the thermometer, making it more reliable.

The 1700s: Standard Scales and New Discoveries

1701 — The famous scientist Isaac Newton anonymously published a way to figure out how fast things cool down. He also introduced his own temperature scale, where 0 degrees was the freezing point of water and 12 degrees was human body temperature.
1701 — Ole Christensen Rømer created one of the first practical thermometers. It used red wine as the liquid! His scale had 0 representing a mixture of salt and ice.
1709 — Daniel Gabriel Fahrenheit built alcohol thermometers that were "reproducible." This meant that if you had two of them, they would give the same temperature reading.
1714 — Daniel Gabriel Fahrenheit invented the mercury-in-glass thermometer. This was a huge step because it was much more precise! He set the melting point of ice at 32 degrees and human blood temperature at 96 degrees. This scale is still used today in some places.
1731 — René Antoine Ferchault de Réaumur created a temperature scale where 0 was the freezing point of water and 80 was the boiling point. He chose 80 because his alcohol mixture expanded by 80 parts per thousand.
1738 — Daniel Bernoulli explained in his book Hydrodynamica that as a fluid (like water or air) moves faster, the pressure inside it actually goes down. This is a key idea in the kinetic theory.
1742 — Anders Celsius proposed a temperature scale where 100 degrees was the temperature of melting ice and 0 degrees was the boiling point of water. This was later reversed to become the Celsius scale we use today.
1743 — Jean-Pierre Christin also developed a scale where zero was the melting point of ice and 100 was the boiling point, working independently of Celsius.
1744 — Carl Linnaeus suggested reversing Celsius's scale. This is how we got the Celsius scale we know, where 0 degrees is freezing and 100 degrees is boiling.
1782 — James Six invented the Maximum minimum thermometer. This clever device can show both the highest and lowest temperatures reached over a period of time.

The 1800s: Electrical and Medical Advances

1821 — Thomas Johann Seebeck invented the thermocouple. This device uses two different metals joined together to measure temperature by creating a small electrical voltage.
1844 — Lucien Vidi invented the aneroid Barograph. This tool could record changes in air pressure without using liquid mercury.
1845 — Francis Ronalds invented the first successful Barograph that used photography to record pressure changes.
1848 — Lord Kelvin (William Thomson) introduced the Kelvin scale, an "absolute" temperature scale. On this scale, 0 Kelvin is the coldest possible temperature, where all atomic motion stops.
1849 — Eugène Bourdon invented the Bourdon gauge, a very common type of manometer (pressure gauge) still used widely today.
1849 — Henri Victor Regnault invented the Hypsometer, a device that measures altitude by finding the boiling point of water.
1864 — Henri Becquerel suggested an optical pyrometer. This tool measures very high temperatures by looking at the light an object gives off.
1866 — Thomas Clifford Allbutt invented a clinical thermometer that could measure a person's body temperature in just five minutes, much faster than before.
1871 — William Siemens described the Resistance thermometer. This thermometer measures temperature by how much a metal's electrical resistance changes with heat.
1874 — Herbert McLeod invented the McLeod gauge, used to measure very low pressures in vacuum systems.
1885 — Calender-Van Duesen invented the platinum resistance temperature device, an even more accurate type of resistance thermometer.
1887 — Richard Assmann invented the psychrometer, which uses both wet and dry bulb thermometers to measure humidity.
1892 — Henri-Louis Le Châtelier built the first optical pyrometer, making it easier to measure extremely hot temperatures from a distance.
1896 — Samuel Siegfried Karl Ritter von Basch introduced the Sphygmomanometer, the device doctors use to measure blood pressure.

The 1900s: Modern Measurement Tools

1906 — Marcello Pirani invented the Pirani gauge, another important tool for measuring pressures in vacuum systems.
1915 — J.C. Stevens created the first Chart recorder for environmental monitoring. This device could automatically record data over time.
1924 — Irving Langmuir invented the Langmuir probe, a tool used to measure properties of plasma (a superheated gas).
1930 — Samuel Ruben invented the thermistor. This is a type of resistor whose resistance changes a lot with temperature, making it very useful for precise temperature sensing.

Timeline of temperature and pressure measurement technology facts for kids

Contents