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The Story of the Thermometer
How we learned to measure hot and cold
Grab your cozy coat and warm mittens as we journey back in time to see how humans learned to measure heat!
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- 200 BCE
Air Moves with Heat
Long ago, ancient thinkers noticed that trapped air expands when warm. They built simple glass tubes to watch air push water around.
The big idea
Thermometers turn warm and cold feelings into exact numbers we can measure.
Fun facts
- ✨ The word thermometer comes from two Greek words that mean heat and measure.
- ✨ Liquids swell up and take more space when they get warm, which makes them climb inside glass tubes.
- ✨ Special infrared thermometers can read heat without even touching your skin!
Science words
- Temperature — A number that tells us how hot or cold something is.
- Expand — To grow bigger or take up more space when heating up.
- Thermoscope — An early invention that showed temperature changes without using numbers.