'Ha, hah......, ha' On the royal boat, Zhao Yu stood on the deck and watched the fleet Yang Fan break the waves on the Grand Canal, they turned back from Lingbi and entered the Huai River from Sizhou, and went down the river from Chuzhou to the canal and sailed to Xuzhou.

Suddenly, I sneezed a few times in a row, and suddenly felt that my eyes were black, all of them were golden stars, and it took a while to regain my clarity, and I secretly scolded in my heart who was thinking about myself!

"Your Majesty, the wind is strong on the river, isn't it infected with the wind and cold, let's let the imperial doctor check the pulse!" Wang De became nervous, and while wiping the dirt sprayed for His Majesty with a silk handkerchief, he persuaded worriedly.

"It's okay, I want to see the scenery along the way, otherwise I don't know when I can come back!" Zhao Yu waved his hand, his eyes still staring at the two sides of the canal.

"Your Majesty, both sides of the strait are wilderness, what is there to see, let's go into the cabin and rest!" Wang De looked at both sides of the strait, only saw small fields and sparse houses in the distance, and occasionally passed by a town that had already shown the appearance of ruin, which really made people not interested, but the little emperor was full of interest, and he was tired of it, and often chatted with several ministers about the past and the present, reminiscing about the past.

"Do you know that more than 100 years ago, this was a prosperous and rich place, surrounded by thousands of acres of fertile land and densely populated, but it is a pity that Du Chong dug the Yellow River embankment to prevent the Jin soldiers from going south, turning this place into Zeguo. Since then, our dynasty has fought with the Jurchens and Mongols here, and the population has been scattered and the fields have been barren for a hundred years. But it also made this canal, and things in the world are so wonderful. Zhao Hao smiled.

Sometimes Zhao Yu also feels that the world is impermanent, in the second year of Jianyan, Du Chong stayed in Tokyo to resist the Jin soldiers to the south, in Henan Huaxian Li Gudu west artificially dug the Yellow River embankment, the Yellow River through Huaxian South, Puyang, Juancheng, Juye, Jiaxiang, Jinxiang and other areas into Surabaya, and from Surabaya into the Huai River, through Xuzhou, Suqian, Huai'an along the Huai River into the sea, this is the history of the famous "Yellow River to seize Si into Huai", since then the Yellow River diverted flow through Xuzhou.

In the Yuan Dynasty, due to the establishment of the capital of Dadu, the political center moved northward, and due to the siltation of the old canal, it was unusable. In order to shorten the land transportation route to facilitate the transportation of grain from the south to the north, the Jeju River, the Huitong River and the Tonghui River were dug in the north of Jining, and the Beijing-Hangzhou Grand Canal connecting the north and south was initially built. The original Jining-Xuzhou Surabaya River and Xuzhou-Huai'an, which were encroached upon by the Yellow River, were incorporated into the north-south transportation system as part of the canal.

Zhao Yu also knew that for hundreds of years after that, the Yellow River in Xuzhou was used as a canal for a long time in the Yuan, Ming and Qing dynasties, but unfortunately in modern times, due to the development of society and the development of road traffic, the role of the canal has been greatly reduced. Coupled with the development of industry, the water volume of the river decreased, the Yellow River began to cut off, and the navigable section of the canal shrank, resulting in the suspension of navigation of the Jiangbei Canal, which has become a historical relic. Now that he is fortunate enough to have a glimpse of the whole picture of history, he naturally feels fortunate and complacent.

"Your Majesty, the canal has been open to navigation for some years, but it hasn't changed much!" Wang De didn't know what His Majesty was thinking, but he was bent on persuading His Majesty to return to the cabin, so naturally he had little interest.

"This is a big bargain for him, a few years after Meng Yuan built the canal, the two sides of the strait have just recovered some vitality, but because we have recovered the south of the Yangtze River, the canal has been cut off again. The rise and fall of the first-line towns of the canal is closely related to the smoothness of the canal and the normality of the canal. When the canal is prosperous, the canal will prosper, and the towns along the canal will also prosper. As a result, due to the gradual decline of the canal's transportation and the weakening of the canal's transportation function, the towns along the canal naturally declined, but it will soon recover and become a prosperous place again. Zhao Hao smiled.

In fact, Zhao Yu only explained the interdependence between Caoyun, canals, and towns from the economic aspect. The opening of the canal is the most political significance, you must know that after the Grand Canal became the main waterway of Cao Yun, Cao Yun with the help of the Grand Canal to communicate the north and south of the convenient conditions, can transport the grain to most parts of the country, become a powerful means of the dynasty to adjust materials, check and balance the society.

Therefore, Cao Yun has always been the indispensable and most important material foundation for maintaining the central power of successive dynasties. Especially after the ancient social and economic center of gravity shifted southward, there was a situation where the political and military center of gravity and the economic center of gravity were separated, and the political and military significance of Caoyun for various dynasties became more prominent. Year after year, the imperial court carried out the transportation of grain from the south to the north, and the grain supplied the daily food of almost all the people living in the capital, and greatly supported the normal operation of the entire central government organs.

At the same time, Cao Liang became an important material force to support the military system of the dynasty, and many of the huge local garrisons distributed throughout the dynasties, the defense and offensive on the long border, and the various wars of the Quartet were all backed by Cao Gong. As Zhang Fangping of the Song Dynasty said: "Today's situation, the country stands according to the soldiers, the soldiers take food as their life, and food is based on luck." ”

"Your Majesty, let's go back to the cabin!" Wang De was not interested in listening to His Majesty's national affairs, he knew that his responsibility was to ensure His Majesty's health, and any other military affairs were floating clouds in his eyes, so he persuaded and dragged the little emperor back to the bedroom, and called the accompanying doctor to check the pulse, and learned that His Majesty was fine, so he gave up, but don't let him out of the cabin again.

Since this area is all newly recovered areas, in order to ensure the safety of His Majesty, the fleet did not stop all the way, and entered Xiapi two days later. At this time, Zhao Mengjin had already led the First Army and the Second Cavalry Division to Yingtianfu in the north, leaving the Fourth Army to garrison Xuzhou, and the Third Division of the Fourth Army stationed here sent troops to escort along the way until they entered Xuzhou. And the commander of the four armies, Sun Kai, has already led the generals in the city to greet here, the fleet docked at the wharf outside the city, and after entering the city to rest for a day, Zhao Yu met with the generals, inspected the city defense, and asked about the situation in the city, and then took a boat to inspect the Li Guojian.

In order to transport iron ore abroad, the Song Dynasty dug a canal from Liguojian, which began at the foot of the southwest mountain of Yang Village, Liuquan Town, and flowed into Weishan Lake after many springs such as Pearl Spring and Sow Spring in Liguo. The river is 16 miles long, the river is the widest 10 zhang, and it was called the "Iron River" at that time, so it was very convenient to take a boat.

Zhao Yu knows from the history books that since the Han Dynasty, Liguo has always been an important place for iron ore mining and smelting in China. At both ends of Baijia Bridge, on both sides of the Yuntie River, there used to be dense iron smelting workshops, fireworks and fireworks, and it was very noisy. After the Song Dynasty was changed to Liguojian, it relied on the advantages of resources to form a complete system of mining, smelting and manufacturing.

After arriving at the place, Zhao Yu already knew that because the water of the Yellow River entered the Huai and went out to the sea through Xuzhou, and then burst and flooded several times, resulting in a large amount of sediment silting up the riverbed, blocking the channel of the water into the Huai, and the flood stagnant into Weishan Lake, flooding most of the mines in Liguo, causing Xuzhou's mining and smelting industry to begin to decline from prosperity. However, the situation in front of him still made him very shocked and disappointed, Meng Yuan also wanted to recover after occupying Xuzhou, and mined the mines near the lakeside, but the scale was greatly reduced because the water gushing in the pit could not be eliminated.

Despite his disappointment, Zhao inspected the existing smelter. Due to the war, the production was discontinued, so he could only ask some craftsmen to learn about the smelting process. It is found that the craftsmanship used here is still very primitive, basically still following the methods of the Han Dynasty, but it has also been improved. As far as the scene is concerned, the smelting has been made of blast furnace iron, the body shape of the furnace is vertical square, the bottom of the furnace body is one zhang three feet wide, about one zhang five feet long, the furnace wall is about three feet thick, and the furnace height is more than seven feet.

The inner cavity is oval, the furnace door is located in the front of the furnace body, the refractory clay is mixed with salt and quartz sand when the furnace is built, ground and mixed evenly, stacked and pounded layer by layer, and dried in the shade. Each iron-making furnace is loaded with 2,000 catties of iron ore, fueled by hardwood or charcoal, and smelted by blast in special leather bags. After the iron ore is melted, the molten pig iron is reduced by a carbonaceous reducing agent, and the molten iron flows out of the waist hole of the ironmaking furnace. Every hour can smelt a furnace of pig iron, and about 700 catties of iron can be obtained. The blast furnace can be recycled, and the molten iron can be immediately installed in the furnace for smelting after it is exhausted.

If you are making pig iron for casting, the molten iron is injected into a strip or round mold. If wrought iron is made, a square pond is built a few feet away from the furnace and a few inches lower, and a low wall is built around it to allow the molten iron to flow into the pond. A few people stood on the low wall with willow sticks, dried the mud in advance, sifted it into a fine powder like flour, and quickly and evenly sowed it on top of the molten iron, and several others stirred it violently with willow sticks, so that the mature iron was quickly fried. When it cools down a little, some people make squares in the pond, while others take it out and hammer it into round pieces. Zhao Yu knew that this kind of process was the iron frying.

The method of steelmaking is to first beat the wrought iron into a thin sheet about an inch and a half long as a finger wide, then wrap the thin sheet tightly, put the pig iron on top of the tightly tied wrought iron sheet, and then cover it with broken straw sandals, and apply mud under the wrought iron sheet. When it reaches a certain temperature, the pig iron will first melt and seep into the wrought iron, and the two will merge with each other. After taking it out, it is beaten, then smelted and beaten, and so on many times. The steel tempered in this way is called steel filling.

Although everything was not satisfactory, Zhao was not discouraged, as he knew that the re-mining of Liguo iron ore had begun during the Qing Dynasty, and although science and technology had advanced at that time, he felt that it was insurmountable now. At present, the most important thing is to survey the area around the old iron mine, find new ore veins, restore the original mine, and at the same time transfer craftsmen from the craftsman's workshop to introduce the previous new technology for innovation, but the relocation of the armory workshop to the north can only be temporarily delayed.

Zhao Yu also planned to go to Xiao County to inspect the coal producing area, but he was persuaded by everyone that the war there had just ended. At this time, Zhao Mengjin also sent news that Ying Tianfu had been recovered, and now he was appeasing the people, repairing the old palace, preparing to welcome him to the sacrifice, and informing the ancestors and ancestors to repeat the Central Plains......