Hand rubbing nuclear fusion live in the wilderness

Chapter 145 Making Ice with Saltpeter - Defining Temperature
Although it is not difficult for him to make glass tubes, it is still quite difficult to make small capillary glass tubes.

The main reason is that the slit inside the capillary glass tube is too small.

After trying various methods such as mold inversion, drilling and blowing holes after forming, etc., all failed, Won still found a way.

A slightly larger thick-walled glass tube is first blown out of a mold, and then heated with a gas blowtorch to keep the glass rod at a high temperature and semi-melted state.

Finally, it is drawn into a smaller glass tube by hand.

This is currently the only way Won can make capillary glass tubes after trying various methods.

After tossing for hours, he finally produced several slender glass tubes.

Although these glass tubes are still very large compared to modern mercury thermometers, this is not bad.

Handmade woolen glass tubes, this is still a thing in the [-]th century.

Once the slender glass tube was manufactured, the rest was easy.

The center of the glass tube is heated by a gas torch, and while it is rotating, it is blown like air, so that the heated part will form a bubble as the glass softens.

The air bubble is what holds the liquid inside the thermometer.

Compared with modern thermometers, the one he made is actually more similar to the thermometer made by Galileo in the sixteenth century.

It's just that the capillary glass tube made by South Korean Won is much smaller and better in terms of accuracy.

The glass tube of the thermometer is made, and the rest is to fill it with colored vegetable oil.

The audience in the live broadcast room looked at the sealed capillary glass tube in Han Yuan's hand, and speculated about how Han Yuan could pour the liquid into it.

After all, the slit inside this thing is too small, and one end is still sealed, so it shouldn't be possible to pour it in.

Han Yuan looked at Zheng Huan's bullet chat, but found that there were hardly a few bullet chats that could talk about the correct method.

Seeing this, he couldn't help shaking his head slightly, and said, "Actually, the liquid in the thermometer is very simple."

"You don't need to use the filling method, blowing method, immersion method, etc."

"When I say a noun, everyone can basically understand it, but you didn't think of it at first."

Hearing this, question marks popped up in the live broadcast room.

Han Yuan picked up a made-up thermometer and said while putting the bubble section on the fire to roast.

"Pressure difference!"

After this sentence, most of the audience in the live broadcast room have reacted, but there are still many audiences who are confused.

【Understood. 】

[High school physics knowledge, no wonder the anchor said we all know it. 】

【I still don’t understand?Is there a big guy to talk about? 】

[It's very simple, just heat the glass tube, the air inside will escape, and then when it cools down, the water will naturally be sucked in. 】

【To be precise, it was pushed in by the atmospheric pressure outside. 】

[Sweep to death! 】

[Upstairs speak human words! 】

Seeing that most of the people had reacted, Han Yuan smiled and said, "As some friends said, during the instant heating process, the gas expands and part of it escapes."

"Using this principle, I only need to heat one end of the thermometer, and then put the other end into the liquid, then under the action of pressure, the liquid will naturally be sucked into the air bubbles in the glass tube."

After Han Yuan finished speaking, the bubble end of the glass tube in his hand was almost heated.

Take off the glass tube, and immerse the unsealed end directly in the red liquid made of monkey wine and red pigment.

The moment the glass mouth is immersed in the liquid, the red liquid automatically climbs up the slits in the glass tube like flowing water.

It's like a straw picking up liquid.

After a while, the red oil in the glass entered the glass tube and filled the bubble chamber.

Seeing this, Han Yuan erected the thermometer, because the bubble chamber was already filled, and there was still some residual oil in the glass tube.

So when the thermometer is erected, the red oil inside slides down the slits, and finally accumulates together at the bottom of the thermometer, turning into a short, thin red line.

It's just that because the glass tube contains impurities, the color is not really transparent, but has a hint of green, so the red oil in the thermometer does not look bright red, but slightly orange-red.

After wiping off the remaining oil on the outside, Han Won showed the thermometer in his hand to the audience.

"Hey, everyone, here's a thermometer that's nearly finished."

"The difference is that the top is melted and sealed, and the marking line is engraved before it can be used."

Seeing the red liquid in the cup flow upstream and finally accumulate in the bubble chamber, the audience in the live broadcast room also admired it.

[Really, the liquid flowed in automatically. 】

[Really learn mathematics, physics and chemistry well, and survive in the wilderness without fear! 】

【Decided, I want to study hard!Struggle for a hundred days and go to Qinghua! 】

[Come on upstairs! 】

【come on! 】

[Who is Qinghua? 】

[Although I don't want to hit you, but dreaming is faster. 】

The remaining few woolen glass tubes were made in the same way, and then the top was melted with fire to seal the slits, and a closed thermometer was basically completed.

The difference is finally marked with a line and a value.

It's just that marking lines and values ​​is not that simple, which requires defining the temperature.

For this reason, Han Yuan dismantled his latrine and got out Glauber's salt.

Even so, what he can define is only zero degrees and one hundred degrees, and other temperatures cannot be defined.

So he needed a material with a very stable coefficient of thermal expansion as the solution in the thermometer.

In this way, after marking zero degrees and one hundred degrees, it can be split into different scales to define other temperature markings.

If it is in the real world, kerosene, mercury, and alcohol will work. The coefficients of thermal expansion of these three materials are very stable.

But he doesn't have the two materials of kerosene and mercury now.

As for alcohol, although the thermal expansion coefficient of alcohol is also quite stable, its boiling point is 78 degrees at standard atmospheric pressure.

Put it in boiling water of [-] degrees, and it will basically expand to explode.

This is why basically all laboratories are equipped with thermometers of three different materials: alcohol, mercury, and kerosene.

Because the melting and boiling points of the solutions in the thermometer are different.

If it exceeds the melting and boiling point, it is easy to burst due to excessive pressure.

For example, the mercury thermometer that was often used to measure body temperature in the past has a melting and boiling point between -33°C and 357°C. Although the boiling point is relatively high, the mercury inside becomes solid when it is lower than 35°C.

The alcohol thermometer commonly used in the laboratory, although the highest temperature measured is generally only 78°C, the lowest temperature that can be measured can reach -110°C.

The comparison between the two deviates greatly, and naturally they are completely different in terms of usage.

(End of this chapter)