The Tuntian military household was the most disadvantaged soldier in the late Tang Dynasty and the Five Dynasties, cultivating and working in peacetime, and being directly conscripted into the battlefield in wartime, somewhat similar to the box army of the Song Dynasty.

However, Li Qi's intention was to imitate the method of the production corps in later generations, and to promote military reclamation in northern Shanxi, Yunzhou, and Shanbei, and to restore the Beifu military system, which had been completely corrupted after the opening of the Yuan Dynasty in the Middle Tang Dynasty, which was a very effective way to strengthen the army in ancient times.

After inspecting the Grange, he went directly to Gujiao, where he discussed the construction of a large iron-smelting blast furnace with the officials who would be the supervisor and the craftsmen of the ironworks.

The larger the volume of the iron-making blast furnace, the less fuel it consumes, the higher the production efficiency, and the lower the production cost.

The earthen blast furnace is not difficult to build, and in the era of "steelmaking for all", it was even everywhere in China.

The inside of this ancient iron-making furnace is like a large vase, but Li Qi knows that the larger the blast furnace is built, the higher the production efficiency, and the less coke will be consumed, and the volume of the iron-making blast furnace in later generations has reached four or five thousand cubic meters. The problem is that the earth blast furnace can only be built to a height of more than two zhang, and if the volume is larger, the current structure can no longer withstand the pressure of molten iron in the furnace.

The ancient blast furnace has always been about two zhang, not that no one wants to make it bigger, but by the structural strength of the furnace body and the furnace wall, afraid of the "fryer", on the other hand, the limitation of ventilation technology.

In ancient times, there were three main reasons that limited the volume of the blast furnace: first, the main fuel used was charcoal, and the charcoal at the bottom was not strong enough to withstand the pressure of accumulating more iron ore above. This should be solved with the use of much stronger coke as fuel. Second, the oxygen supply is insufficient, which cannot support the full combustion of fuel in the furnace, and this problem should be partially solved after the installation of large hydro-driven blowers and the construction of higher chimneys. Third, the strength of the furnace structure is not enough, the main structure of the blast furnace in later generations is made of steel and cast iron as the main support to enhance the structural strength, and the old clay shaft furnace can certainly not achieve such strength.

The structure of the iron-making shaft furnace in China was already very mature in the Han Dynasty, and it is very similar to the early iron-making blast furnaces in the West in later generations, with the only difference that it seems to be missing a large chimney that is thick and high.

The bellows or even the water discharge of the linear reciprocating movement cannot continuously provide fresh air to the blast furnace, so it must be improved to do a blower for circular movement. There is not much difficulty in the blower, and the principle can be understood with a little explanation. In ancient times, due to the high price of iron, craftsmen were greatly limited in the production and use of iron tools, and without sufficient practical knowledge, such simple things could not be made.

The blower is a volute with a fan inside, and the problem is that the impeller needs to be cast from good steel. The price of stainless steel is 150 wen per catty, which is equivalent to 100 catties of corn, and no one is willing to use it for experiments. Moreover, due to the low status of craftsmen, and the fact that the iron supervisors and even the owners or managers of iron-smelting workshops basically do not understand technology, there has been no great progress in iron-smelting technology since the Han Dynasty.

After solving the problem of the blower, the problem of the blast furnace could only be put on hold for the first time.

To make the furnace taller and bigger, the only way to make it bigger is to use the steel structure and the outer walls, which requires hundreds of tons of steel. This is almost a year's output of the current Gujiao Iron Workshop, and it can only be temporarily stopped. It can only be made of old-fashioned brick and earth iron-making blast furnaces first, and then build a new large blast furnace when the steel materials are enough.

Due to the need for water turbines to drive the blowers for strong ventilation, these blast furnaces had to be built on the edge of the dam culvert.

As the prime minister, Zhang Xian followed Li Qi's side and watched him arrange the planning and construction of workshops everywhere, and he still saw many wonderful production techniques. For example, the cement produced in the workshop, the fertilizer, the iron-making and steel-making, the water-powered spinning machine and the loom, and a very magical transparent glass.

Before the wheat harvest, Li Qi demanded that a barrage dam be built on the Jiaocheng Ciyao River, and that the Jiaocheng Datong Iron Supervisor be moved from the slope of the mountain to both sides of the riverside dam.

It stands to reason that the Jiaocheng Supervisor is an important source of wealth and should not be lightly moved.

But now, the cement has also been fired, the iron-smelting workshops in Gujiaocheng and the weaving workshops of several manors continue to create wealth for him, and there is no shortage of manpower around Taiyuan - beating children on rainy days, idleness is also idle. So, Li Qi gritted his teeth, and the barrage project began to start again.

According to his design, the Yangxing River dam built in the Ciyao River is more than three zhang wide and six zhang high, and the amount of earthwork is not small. Li Qi's demand is to realize the closure and storage of water in the reservoir before the autumn flood in August. According to the plan, on both sides of the dam, along the four main aqueducts, an iron-smelting workshop and a weaving workshop will be built on a much larger scale than the Tushui Lutai Huangzhuang workshop.

In this era, the profits of slightly more advanced machine workshops are too high.

For example, the iron-smelting workshop built by Li Qi in Gujiao is not much more advanced than the iron-smelting workshops in Jiaocheng and Zezhou, but due to the use of water turbines as the power, the efficiency of iron-smelting, steel-making and forging has been improved by several times. Now, in the Gujiao Iron Workshop, the cost of each pound of pig iron is only about 8 Wen, and the price of iron on the market has exceeded 40 Wen per catty, and the price of stainless steel is as high as more than 150 Wen per catty.

The Ciyao River Dam is the first concrete gravity dam in the world, and several of the dams built by Li Qi before are bluestone earth dams. Although the concrete dam was basically tied with bamboo as a skeleton due to the lack of steel, it was a standard "tofu slag project" in later generations, but in this era, it can indeed be called a grand project.

Because of the abundance and cheapness of wool in the Northland, the weaving workshops of several estates are now thriving, and the crimson cloth woven and dyed has become one of the most sought-after goods for caravans on the steppe.

The construction of barrages and dams is a major event that benefits the country and the people, and it is also a great opportunity to become famous in the world in one fell swoop. After the completion of the Ciyao River dam and the start of the reservoir to store water, the 18-meter-high barrage dam can allow the reservoir in the river valley to store more than 100,000 cubic meters of water, plus some water conservancy and irrigation facilities planned and constructed, half of the farmland around Jiaocheng County will be able to be irrigated, and this change alone is enough to feed tens of thousands of people around Jiaocheng.

Although Jindi is closed, it does have a very good prospect for industrial development due to the abundant coal and iron resources.

Inspecting the barrage dam under construction and the attached water conservancy facilities and hydraulic workshops really made Li Jiqi feel a great sense of accomplishment from the bottom of his heart.

It's a good start.

He felt that since he had come to this world, he had an obligation to spread the seeds of industrial civilization in this world. Only after entering the industrial age will the ancient Chinese civilization become stronger and stronger in this world, and no longer suffer from the great destruction from the barbarian tribes.

Now the new textile machines and looms manufactured in various estates have gradually increased the proportion of steel parts, and some of the smaller and more vulnerable parts of these machines have been replaced by more durable steel or iron parts, but due to the current high iron prices, some large structural parts are still mainly wood. If the price of steel falls to a reasonable level lower than that of wood, it is conceivable that steel will replace wood as an inevitable trend.