The iron cast cannon is not without disadvantages, because the heat dissipation of iron is relatively fast, resulting in the cannon cooling speed is too fast, the gun will be more brittle, affecting the service life of the gun.

Although Changsheng Island heats the iron fan when casting the artillery, the method of wrapping the iron fan with hot furnace ash after the casting is completed allows the cannon to cool down slowly, so that the cast cannon is on the same level as the cannon cast by the Franco.

With the internal mold water cooling technology, Changsheng Island will surpass the West in the casting process of artillery and lead the world.

This time, Zhang Dou brought back a large number of gunsmiths and shipbuilders from Macao, and the Han Chinese among them were directly sent to artillery workshops and shipyards.

The Francs and Dutch sailors were sent to the top of the North Hill to repair the Martyrs' Shrine, where they were to be reformed through labor. Let them work for a month, and then let them experience the hellish life, and these people will not know to work hard.

Sun Hejing presided over the wind machinery has also made great progress, and the bearing can not be made with the current technology. However, the bearing is not a difficult task, and the steel shaft copper tile is lubricated with whale oil instead of the traditional wooden workpiece.

This technological improvement made the windmills on Changsheng Island rotate faster and more powerfully, not only for the drill pipes, but also for the blasts of the ironmaking workshops to be changed to wind power.

Sun Heding was less serious, and it took him a month to complete the experiment with soap and glass. He then went to the shipyard and took part in the final construction of the sloop.

The blade-like bow of the ship was his handiwork, and the cargo was going to add a sail to the ship. He later broke two masts, but he designed a sail that did increase the boat's speed. It's just that the pure wooden mast can't bear it at all, but Zhang Dou still admires the Sun family. In this way, Sun Heding got the ball sail of the later generations, and one day the Sun family said that it would not be strange for them to make a steam engine Zhang Dou.

It's just that the cost of the new sloop is a bit expensive, and it costs two thousand taels of silver. This is already more than double the price of an ordinary sea ship of this size, and Zhang Dou did not hesitate to build ten on the spot. The current Zhang Dou is not short of money, and the Galen ship Zhang Dou also plans to build five new 500-ton warships.

These plans suddenly made half of the money he got back from Macao disappear, plus enough to buy food and various materials, Zhang Dou calculated that he didn't have much silver left.

Could it be that Daming's silver could not be depreciated, if he hadn't made the glass and soap, he would have planned to rob again.

When Zhang Dou returned to the room, it was already the time to turn on the lamp, and he had just put his tired body on the bed when there was a knock on the door.

A voice came in: "Brother Shi! Slept? ”

Zhang Dou sat up straight all of a sudden, straightened his clothes and opened the door.

Sun Yuxiu stood timidly at the door with a food box in her hand, she handed the food box forward and said, "Brother Shi! This is a meal made by my little sister, and I don't know if it suits my brother's taste! ”

"Hop! Definitely! Zhang Dou said with certainty that no matter how unpalatable the food cooked by his fiancée, it must be to the taste.

Zhang Dou let Yuxiu into the house and took out a small mirror from his arms.

"Yuxiu! Zhang Dou is a rough person, and he doesn't know what to give you. This mirror is given to you, and I hope Yuxiu will not dislike it! With that, Zhang Dou handed the mirror to Sun Yuxiu.

Sun Yuxiu took the mirror, her fingers intersected with Zhang Dou's big hand, and she couldn't help but two red clouds flew up her cheeks, and she quickly turned around to focus her attention on this small mirror.

The mirror was only the size of a palm, much finer than the Xiyi glass mirror she had seen before. The rosewood frame is also inlaid with several gemstones, and the ivory handle is indeed a rare boutique.

This was specially picked out by Zhang Dou from the things seized by the Macau Council, and he always carried it with him to find an opportunity to give it to Sun Yuxiu.

Sun Yuxiu was carefully looking at the mirror in her hand, and suddenly her body was hugged from behind. She stiffened, then softened and leaned against her broad chest behind her.

Zhang Dou ate this meal extremely happily, but at the critical moment, the throat of his mother-in-law made Sun Yuxiu escape like a gust of wind.

The depressed Zhang Dou could only sleep alone, and the next morning, the two dogs came to knock on Zhang Dou's door.

"My lord! Dog Tartar Emperor Taiji has moved! When Zhang Dou heard Ergou's words, he suddenly sobered up.

He hurriedly opened the door to let Ergou in, and asked, "What's the matter?" ”

"Huang Taiji has been buying cannons during this time, and now there are fifteen general cannons that have been identified. There were also many other types of artillery, and most of them were transported from Liaozhen. After listening to Ergou's words, Zhang Dou's eyebrows were twisted into a Sichuan character.

Where did Liaozhen get so many cannons, and it wasn't used by the master and apprentice to build the defense of Xiutun Fort! Now it has been sold to the enemy, where is this digging the corner of the Ming Dynasty, it is clearly digging the ancestral grave of the old Zhu family.

The Jurchens were good at field warfare and had poor ability to attack fortified positions. With these artillery, Sun Chengzong cultivated those tunpu cities that were not vulnerable at all.

Who did this?

"Find out who sold the Huang Taiji artillery?" Zhang Dou asked.

"Nope! The Jurchens don't know much about this, and we Shadow people have tried their best to know where the artillery is stored. Aren't we ......?" said Ergouzi excitedly.

"Are you sure?" Zhang Dou asked.

"Yes! There are our people in Fuzhou City, did the handsome ever remember Liu Xingren? Zhang Ergou said.

Zhang Dou nodded and said, "If you are sure, don't startle." Stay safe! It's better to abandon the mission than take the risk, remember? ”

Zhang Dou's advice moved Zhang Ergou very much, and he beat his left chest hard and gave Zhang Dou a military salute and said, "Handsome! The second dog will complete the task! ”

After saying that, he turned around and walked towards the door, and the moment he left the house, he turned around again and said, "Dashuai! The little one has changed his name, it's called Zhang Wei! With that, he strode away.

Fuzhou City has now become a large barracks, and the people in the city dare not go out during the day. Those Jurchen masters are so terrible, they are not reasonable at all.

Robbing people's daughters is not a matter at all, and it also happens from time to time when encountering Han people who are not pleasing to the eye.

Although Huang Taiji tried his best to restrain the Jurchens, as the victors, they always had the feeling that everything was theirs of the Han people.

The Jurchens generally believed that the timid and cowardly Han people did not deserve to own the splendid rivers and mountains in the south at all, that they were born slaves, and that all this should belong to the great Jurchens!

Therefore, the Jurchens did not regard the Han people as human beings at all, and it was natural to kill the Han people.

"Big brother! We can't bear it any longer, three brothers have already been robbed of their wives and daughters by the Jurchens this month. If this continues, the brethren will be scattered! Liu Xingren roared at his eldest brother.