Things on the Xishan side are slowly becoming regular, and Liu Jin is also a lot more relaxed, he has spare time to be busy with some black technology, and recently Liu Jin has been busy firing glass.

Glass is not uncommon in later generations, it is very common, household window glass, car glass, to special bulletproof glass, tempered glass, etc., all kinds of glass products are countless, with different functions.

In this era, glass is a rarity in the Ming Dynasty, only a very small number of merchants from the Western Regions carried a small amount of glass products from Europe, such as some glass wine bottles, glass products and the like, the price is extremely high, the key is that the quantity is very rare.

It was only when the European colonists opened up the routes to the East, continuously transported things from the West to the East, and then transported the silk and porcelain from the East back to Europe, that the number of glass products gradually increased, but it was still not something that ordinary people could use.

The reason why Liu Jin wants to burn glass, on the one hand, is for money, Xishan Coal Industry has a big business, and the daily expenses are very huge.

On the other hand, it is also because his student Lin Shuhong wants to follow the fleet to the Golden Continent, and he also wants to get him a telescope, which is not possible without a telescope for navigation.

With glass, you can make glass bottles and the like, and you can make some canned vitamins yourself, and when the time comes, you can bring them to the fleet, and you can also prevent sepsis.

In this era of immature seafaring technology, if you want to cross the Pacific Ocean to reach the Golden Continent, in addition to the geographical knowledge you teach, some other things are also essential.

As long as Liu Jin can think of it, Liu Jin will also prepare it for his students as much as possible, and equip the fleet side.

The matter of this Golden Continent is also said by himself, whether this fleet can successfully arrive at the Golden Continent and come back safely is related to his future fate, and no one is more concerned than Liu Jin.

In the workshop of the honeycomb coal stove in Xishan, Liu Jin alone asked people to build a small stove for himself to study the firing of glass.

"Quartz sand ~ borax, boric acid, limestone, feldspar, barium carbonate ~"

Liu Jin carefully inspected the same raw materials that people collected, the raw materials of glass are very simple and very common, they are everywhere, but it is not difficult to collect.

Glass is also very simple to fire, it does not require a high temperature, a temperature of more than 600 degrees can almost melt most of the raw materials.

Generally speaking, when it reaches 1500 degrees, all the raw materials can be perfectly blended together and the air bubbles in the glass are completely eliminated.

The temperature of more than 1500 degrees is not difficult to achieve, and it is completely achievable in this era, you must know that the temperature of the general charcoal fire can reach more than 700 degrees on the earth, and the temperature of the relatively closed bellows furnace of the blacksmith can reach 1000 degrees.

Liu Jin changed the structure of this kiln slightly, and then added a blast device to this kiln, which can increase the supply of oxygen, Liu Jin estimated that it would reach 1500 degrees, and it should be no problem to perfectly integrate all the materials and remove the bubbles in the glass.

"Almost no problem~"

"The second tiger has worked~"

Liu Jin carefully inspected all the raw materials, and made a detailed record of each raw material, so that an experimental record can be formed, and the next operation can be modified and summarized according to the previous operation.

"Okay~"

Hearing Liu Jin's order, Zhao Erhu began to get busy.

Bags and bags of glass began to pour into the furnace, and then he pulled the bellows like a tireless ox.

Since Zhao Erhu followed Liu Jin, he didn't have to worry about food and clothing, not to mention big fish and meat every day, at least three meals a day, it was a full meal.

Compared to his own home before, not to mention three meals a day, he can only eat half full for two meals a day, and as for eating meat, he can only taste it when he dreams.

Following Liu Jin, his whole person has eaten stronger, he was originally tall, like a bear, but now it is simply a humanoid tank.

The bellows was pulled by Zhao Erhu, and the stove was filled with charcoal, the best horsemouth firewood, and with the entry of a large amount of oxygen, the charcoal inside also began to burn.

The original red color slowly turned white, and the temperature became higher and higher.

With the continuous rise of temperature and continuous heating, all kinds of glass materials in it also begin to melt continuously, slowly fuse together, and begin to form something in a red fluid state, which is glass.

Liu Jin was not in a hurry to get the burned glass out, but he was also a person who had traveled over in later generations, and he had learned some chemical knowledge to some extent, plus he had read a lot of historical novels, among which burning glass was a necessary skill for crossing the party.

I've read a lot of historical novels, and I don't know how many times I've read fired glass, and many of them have mentioned that the glass of this fired glass should be stirred, so that it can be better integrated, and the impurities inside can be removed more cleanly.

It can also reduce and eliminate the bubbles in the glass as much as possible, which is actually carbon dioxide, which is the impurity produced by the chemical reaction of various raw materials after high temperature firing.

If these impurities and bubbles are not removed, the fired glass will have color, and the presence of bubbles will also seriously affect the quality of the glass.

In addition, if you want to make money from this glass, Liu Jin is also preparing to make some glass crafts and other things, which have too many impurities and bubbles, but it will seriously affect the value of this craft, and it will not be sold at a good price at that time.

Liu Jin held a long iron rod in his hand, put the iron rod into the furnace and began to stir, while stirring, he also observed, and saw that there were more melted raw materials in it, and when the heat wave escaping was more pressing, Liu Jin also directly used the iron rod to get some glass out, ready to see the effect.

When the glass is just baked, it is red, and it has very good ductility, and the processing of glass products is carried out at this time, and what shape is needed to make it into what shape, if it is to be made into a bottle or the like, then it is necessary to blow the glass, and use the hollow stick in the middle to connect, and constantly blow air into it.