Use "house slaves" to do business, conduct handicraft production, or engage in commodity management. Not only are the vassal kings, but also the same is true for the gentry and wealthy families. After all, the power of individuals is limited.

For Shi Yiwen, who had been in the Wanli period for more than a year, Jiang Fangzhong's offer was his first real "family slave". After all, before that, whether it was Xiao Lian, Kou Yun and others, or even Chen Huan bought in Songjiang, they were passively accepted, and only Jiang Fangzhong was actively accepted.

Perhaps, this is also a manifestation of some adaptation to the times.

Of course, this adaptation is also due to this need.

Shi Yiwen naturally looked down on the glazed workshop brought by Jiang Fangzhong when he presented the offering. According to the rules of offering, he "rewarded" the workshop again. Just like the land he presented, the land was only nominally returned to the head of the family. At the same time as the offering, he had to pay back the reward. The devotee only handed over the taxes that should be given to the government and the service department to the head of the family. As for the house land, he still had to pay back the reward.

Otherwise, no one would be so crazy that he would give all the house to others and go to his master to be a slave with a shameless face. That would be not a offer, that would be a brainless person.

Compared with the unworthy property of the Jiang family, Shi Yiwen values ​​people. With people and craftsmen, this glass factory will naturally be built in Lugou.

The construction of the glass factory is fast. Because I just want to practice the technology, I just built a reflector for molten glass in the iron plant, and then started to make glass. The raw materials for producing glass are very simple - quartz sand, limestone, feldspar and soda ash, which are all ready-made materials. As for natural soda ash, they are mainly produced in salt lakes, and have always been an important commodity for out-of-mouth production.

According to the glass formula found in the library, the prepared raw materials were heated in proportion by high temperature in the reflector to form a uniform bubble-free glass liquid. The melting process took about eight hours.

"Young Master, our stove is really extraordinary. It has turned into water in just four hours. If it is placed on the old stove, it will take at least a day and a night."

Seeing the raw materials in the furnace melting into glass liquid, Jiang Fangzhong had no doubts in his heart. Not to mention anything else, it was worth it to be dedicated to the Shi family just for this furnace. He was even thinking in his heart that he would replace the furnace in the workshop with such a furnace in the future.

Looking at the change of Jiang Fangzhong's eyes as he stared at the furnace, Shi Yiwen, who knew what he was thinking, also poked it out and asked instead.

“Can you blow it now?”

"It's certainly OK, it's all turned into water."

As he spoke, Jiang Fangzhong's heart thumped into his throat. Now, the young master is going to teach him how to make flat glass?

"In this way, you first tap the iron blower into the stove and dip it in some glass liquid..."

Standing in front of the hot furnace, Shi Yiwen took guidance, while Jiang Fangzhong followed suit.

"After taking it out, turn it and blow it through the blower... Yes, that's it... You also watch, make the glass liquid slowly expand into a spherical shape, and then put it in this semi-spherical iron groove to continue rotating. Yes, make the spherical shape round..."

While guiding Jiang Fangzhou, Shi Yiwen also paid attention to the craftsmen around him. After all, producing glass in the future is not a matter of one person.

"There is a little cold water in this iron tank that can take off and lower the cooling effect. At the same time, use water to cool the other end of the blower for easy control. Look, the glass has cooled slightly, then the blower is inserted into the tank furnace and dip it twice. Repeat this way many times until the glass liquid becomes a ball with a diameter of about 20 cm, then put it in a scoop-shaped iron tank. While continuing to cool the lower end of the blower with water, blow air from the upper end, so that the ball gradually increases and becomes a cavitation..."

Seeing that the red glass balls turned into a vacuolate glass ball under Jiang Fangzhong's blow, Shi Yiwen continued to say.

"You should pay attention to turning the blower at all times during the blowing process to make the spherical cavitation thin and even thickness. This is very important. If the glass temperature drops, then heat the blower deep into the oven to make the glass bubbles soft. At this time, then hang the blower in the air in the deep ground groove and blow air from the upper end, and the glass bubbles will slowly fall into the ground groove, forming a cylinder shape..."

Under Shi Yiwen's guidance, Jiang Fangzhong followed his guidance and worked according to his guidance, but he had a lot of doubts in his heart. Didn't he want to make flat glass? What is this for?

"...The thickness of the glass cylinder is not uniform at this time, generally with a thick bottom and a thin top. However, the glass cylinder has cooled and solidified and cannot be blown again, so it must be re-entered into the oven for heating. After melting and softening, it will be taken out, swing and rotating in the deep groove, and blowing air at the same time. The purpose is to make the thickness of the cylinder wall evenly. If it is cooled again, enter the oven again, and repeat this, and finally blow it into a glass cylinder with uniform thickness, which can reach up to two meters long..."

Of course, due to lack of skill in technology, Jiang Fangzhou only blew out a glass cylinder about one meter long, but even so, it was beyond Shi Yiwen's expectations.

Then, the rest is simple after blowing the glass cylinder into a single blower, dark patterns are created on the glass cylinder through the principle of hot and cold shock. Then, the rotation side is changed and tapped, remove its bottom, remove it from the blower, and then cut into several sections in the same way, cut each section vertically, and finally enter the pan furnace to spread the cylinder into a flat sheet.

In this way, when the plate was released, a few pieces of shiny flat glass would take shape. Although due to the process, there were inevitably dark patterns and spots on the glass. However, after the plates of flat glass were annealed and released, Jiang Fangzhong and the craftsmen around him were stunned.

"This, is this glass really blown out?"

Although it was the glass he made himself, Jiang Fangzhong still seemed very surprised.

"Yes, this method is called blow-drum spreading method."

Until the early mid-20th century, this artificial blower spreader was the most important method for producing flat glass, and it was even not eliminated in many countries until the late 20th century. It was this seemingly backward method that allowed cheap glass windows to enter thousands of households.

"Young Master, this method is indeed not difficult, not difficult..."

In addition to being surprised, looking at the shiny pieces of glass, especially when they were lifted down, looking at the nearly transparent glass, a complex look appeared in Jiang Fangzhong's eyes, and his breathing even became a little rapid. The eyes stared at the glass and moved with its movement. So much so that he himself did not notice the change in his expression. Just then, he heard someone say in his ear.
Chapter completed!