In itself, the shipbuilding technology of the Sui and Tang dynasties was already ahead of the world.

The ship has advanced technology, scientific structure, huge shape and strong stability. For example, the watertight cabin structure greatly enhances the safety of resistance to wind and waves. Mortise and tenon jointing and putty twisting technology extend the wood and can build large ships. Moreover, the ship's side is equipped with a wave guard, shaped like a falcon's wing, which can not only prevent rolling, but also cover the waves, and protect the safety of people and goods on the deck. In addition, four long thick logs were installed on the side of the ship, and the spikes were firmly combined with the two sides, which was called "Da La". The wax not only protects against external impacts, but also strengthens the stability of the hull itself. The Anhai ship built in Quanzhou, "the silver ship has 15 grids on the side, which can store goods as much as 2 to 40,000 stones." "Fifteen compartments, i.e. fifteen bilges.

On the other hand, the foreign ships at that time had brittle wood, coconut skin as a rope connection, olive sugar filling the gaps, and rarely using nail tenons, so the hull was small and the wind and wave resistance was poor.

Sea ships passed through Tianzhu, and the Tang Dynasty ships paid 1,000 local silver coins, and other countries ships paid 20, and at most 200 local silver coins were enough. The Tang Dynasty's ship export tax was 4.5 times more than that of ships in other countries, or even 45 times. It shows that the Chinese ship carries a lot of cargo and the hull is so large.

Therefore, Datang's sea ships, put into the world, are already "sea hegemons" in themselves.

Now, after the technical improvement of Xia Hongsheng and these shipwrights, Datang's ships are more advanced, especially the addition of steel materials, which makes the sea ships stronger. Lacquer and tung oil coated on the outside of the iron sheet can also be used to prevent rust and seawater erosion. The improvement of the sail made it reach the level of the Song Dynasty in later generations - "the wind comes from all directions, but the head is not feasible", that is, in addition to the direction of the head, the ship can go in seven other directions, or adjust the mast sail from seven directions, so that as long as it is not the direction of the head-on wind, it can sail with the help of the wind.

It can be said that the use of the technology of this iron ship, the large ship built, combined with the existing navigation technology, has been enough to reach the level of the Ming Dynasty treasure ship in later generations, and the scale, equipment and technology have surpassed the Spanish and Portuguese sea ships when the Age of Exploration was opened in later generations.

If you want to take the sea ship to the next level, you have to count on the appearance of the steam engine.

All the shipwrights who participated in the construction of this iron ship were very richly rewarded. Of course, their families have all been taken to the military aircraft workshop to house the families of craftsmen. And these shipwrights, on the fourth day after Li Shimin saw the iron boat, set off from Chang'an, escorted by the Datang Blade team, and set off for Quanzhou.

There, there is a larger, more professional dockyard ready for them, and they are going to be there to build the first ironclad battleship in the true sense of the Tang Dynasty.

Naturally, Xia Hongsheng has made great contributions again.

Counting the previous gunpowder and firearms, it is two more world-famous achievements.

Even if gunpowder is considered a dowry for Li Laoer, then the ironclad ship should always be rewarded, right?

However, there was still no movement, and Li Lao Er was already numb to the fact that Xia Hongsheng had made a contribution to the world.

That's why Li Shimin said to Xia Hongsheng - "I really can't think of any reward for you now." In terms of money, you are not lacking, in terms of status, now you are the founding county marquis, a Zhonglang general, or a doctor, if you are mentioning it, it will cause countless criticisms. So after thinking about it, I can't think of a result, so I have to ask you, what kind of reward do you want? ”

So Xia Hongsheng said: "Since Your Majesty asked so, then Weichen will have the courage to say it, Weichen wants some people who understand our Chinese dialect and Daqin dialect." I also want to do something in astronomy, algorithms, and geography...... And so on, only those who are proficient in these miscellaneous sciences come. If Your Majesty can help Weichen find this kind of person, it will be the best reward for Weichen. ”

So, Xia Hongsheng got a few old men.

The author of the textbook "Ancient Arithmetic" of the first subject of arithmetic in Guozijian Middle School, Wang Xiaotong.

The fifth ancestral astronomer Yu Jian.

There are also Fu Renjun and Cui Shanwei.

They are all powerful people who combine knowledge of arithmetic and astronomy.

They also have one more common characteristic - the official is not big!

Perhaps, people who are good at studying knowledge are not willing to put so much energy into running officialdom.

As soon as the edict was issued, they all retained their original positions and were ordered by the emperor to teach at Jingyang Academy.

Xia Hongsheng naturally had to hold a family banquet to welcome these new chairs.

Not to mention anything else, one person and one house first!

Build so many villas, just to keep people! When there is no shortage of teachers in Jingyang Academy, then consider selling the villa area of the school district. Land, more, and the money to build villas is not lacking. That's how capricious!

The new professors were naturally surprised by Jingyang Academy. Gavenda and the others were very nervous to teach them how to use the many novelties in Jingyang Academy, looking at their shocked expressions, not to mention how proud they were in their hearts - gradually, they had a heart for Jingyang Academy.

The shipbuilders went to build ships, and the gunpowder and firearms were arranged by Li Shimin, and Xia Hongsheng was finally idle again.

The days in Jingyang are easy and comfortable, get up every day to visit Jingyang Market, go to Zhuangzi to take a look, run to the edge of the field to take a look, idle for a while. Go to the academy for a few classes, and run to see Daoist Zhang and the alchemist from Daqin alchemy. Those two people can't understand each other, learn to speak with each other, compare with each other, and can still quarrel together, it's amazing.

Xia Hongsheng saw that the two of them were arguing, so he grinned badly on the side to see the joke. The so-called watching the excitement is not a big deal, so Xia Hongsheng secretly said in his heart that he would fight, fight!

Just thinking about bad thoughts, I suddenly heard a sizzling sound, and suddenly saw that the Taoist priest was not quarrelling, and when he looked back, he suddenly slapped his thigh and shouted: "Oops! It's all your fault for pestering the poor road to quarrel, the green alum in the poor road stove has been burned overburned, and it has become green alum oil! ”

As he spoke, he took up the basin and poured it over.

"Wait!" Xia Hongsheng shouted to stop him.

The sizzling sound sounded familiar, Xia Hongsheng ran over to take a look, and saw a stream of transparent liquid slowly flowing out, and the place he passed slowly turned black, and he couldn't help but be surprised.

This is...... Sulphuric acid?!

"Daochang Zhang, what is this?" Xia Hongsheng asked.

"Back to the Hou Ye, this is alum oil." Zhang Laodao complained to Xia Hongsheng: "Originally, this was a furnace of good green alum, calcined into powder, and it became a good material. It's a pity that this beard is too hateful, and he insists on quarreling with the old way, and if he accidentally passes the fire, he will be calcined into green alum oil! When it becomes alum oil, it can't be used. This alum oil is very domineering, but anyone who touches it will be called to melt! (To be continued.) )