Chapter 122 (1/2)

The process of blowing glass was very smooth. Although two vials and one glass tube were blown out in the middle, four qualified vials and four qualified thin glass tubes were finally obtained.

With these two things, there is no difficulty in making a simple thermometer.

Old wood was called over. Of course, he came with his carpentry tools and a little bit of oak.

It didn't take long for old wood to make four small oak stoppers with holes in the middle.

The size of the oak stopper is just enough to plug the mouth of the small glass bottle, and the hole in the middle just allows the glass tube to pass through the middle.

Momo grass has pigment extracted from plants to dye cloth. The stone bear will come a little, then melt it into water, and pour the indigo water into four small bottles. After filling, use the cork to plug tightly. Finally, insert the glass tube from the small hole of the cork to the top of the vial.

Next, use melted wax to seal all the gaps between the small hole and the glass tube.

Because of capillarity, the indigo water in the vial climbs a certain distance along the glass tube, making the water in the glass tube a little higher than the glass bottle.

Finally, the stone bear drips two drops of peanut oil from the top of the glass tube. The role of these two drops of oil is very important. They can form an oil film on the upper layer of the water surface in the glass tube, which can prevent the water in the glass tube from being evaporated.

At this time, it is suggested that the thermometer should be almost done. It only needs to mark the temperature values from the glass tube to complete the simple thermometer.

It is not very difficult to draw a more accurate temperature value on the glass tube.

In later generations, even primary school students know the principle of heat expansion and cold contraction, and the thermometer is made by using the principle of liquid heat expansion and cold contraction.

Now North America has entered the coldest ”long night month”. In terms of the Cherokee era, it is December, but actually it should be between the middle of December and the middle of January in the Gregorian calendar.

Because the Cherokee epoch is calculated according to the full moon, which is a bit similar to the Chinese lunar calendar, so there is a certain gap with the Gregorian calendar date.

In the coldest long night month, after night, even at the foot of the fog mountain, the temperature will be below zero. Let alone two days ago just had a heavy snow, snow is not cold, snow is cold, now is the coldest time.

In order to make a simple thermometer, as early as last night, the stone bear took a wooden basin of water and put it outside to freeze. After the night, the water in the wooden basin has been frozen for a long time.

Pour out the ice in the wooden basin, smash it into several large pieces, and then mix the cold water into the wooden basin. At the same time, there were four small bottles with glass tubes inserted in the wooden basin, most of which were immersed in the ice water mixture.

After waiting for more than ten minutes, the temperature of the basin reached zero. The temperature of ice water mixture, even in later generations, is the best reference temperature of zero centigrade.

At this time, the indigo water column level in the glass tube also stabilized at a height, which represents the temperature value of zero degrees Celsius.

Mark from that position, then stone bear takes out four small bottles with glass tubes, puts them into a frying spoon with a flat board under it, and adds cold water.

The height of the cold water is one block lower than the mouth of the bottle, and then the fire is ignited to boil the water.

Because the glass bottle is heated together with the cold water, there is no need to worry about the small glass bottle exploding.

The water in the frying spoon is not too much, so it boils quickly.

The reference temperature at this time is 100 ℃.