温度計をつくる／Making a Thermometer

DENJIRO: I made an ant with glass. Now, let's make a thermometer. We'll start by making a thin tube, also known as a capillary tube.
I'm going to blow air into the tube to inflate one end into a sphere shape, forming a liquid reservoir. The liquid in a thermometer was once alcohol, but now, they contain kerosene instead because it allows us to measure higher temperatures. So, how will I get kerosene into the liquid reservoir we created earlier?
First, I'm going to warm up the reservoir in warm water, causing the air inside to expand. Turn the tube upside down and dip the open end in the kerosene. I am now cooling the reservoir using this cooling spray. This temperature disparity causes the air to contract, and the kerosene gets pulled into the tube. By repeating this a few times, the kerosene will gradually accumulate in the reservoir.
ON-SCREEN TEXT: Use centrifugal force to get the kerosene into the reservoir.
Seal the tube shut.
DENJIRO: To confirm that this thermometer is functional, place it in warm water. See how the kerosene flows up the tube? And if I place it in ice water... the kerosene flows down the tube. The kerosene moves up and down because it expands and contracts depending on the temperature.
Place the rod in a board like this with the temperatures labeled on the side, and our thermometer is complete!
ON-SCREEN TEXT: A thermometer with markings was invented by an Italian named Santorio in 1612 (Various theories exist.)
DENJIRO: Prior to the invention of this thermometer, all we could do was rely on human perceptions to determine whether it was hot or cold. The advent of this tool enabled us to measure temperature in an objective manner and has played a significant role in scientific development.
I hope energy will bring you all happiness. Our magic word is "Happy Energy!"