Datang: Li Shimin begged me to rebel

According to Li Ke's estimation, if all these factors are taken into consideration, the average sea speed of a large sharp-bottomed modern sailboat can reach a speed of at least 15 kilometers per hour, which is about 8 knots.

Converted at this speed, with the help of the sea chart, you can reach the Persian Gulf in about one month to one and a half months by walking a straight-line distance in some sea areas!

Calculated according to the theory Li Ke said before, if the country can be controlled within a month from the imperial capital, if combined with the ocean, the controllable land area of ​​the Tang Dynasty is not small.

Li Ke raised his head again and looked at the map hanging on the wall. Li Shimin and Li Chengqian were a little confused, so they all looked at the map like Li Ke, and didn't know what he was looking at. If they only looked at the ocean, this road is indeed far enough away.

"Father, I need your authorization." After a long time, Li Ke suddenly said.

"Authorize what?" Li Shimin was a little surprised.

"It's enough for the three of us to know about this matter. The courtiers must not know, or they must not know the real purpose." Li Ke said in a serious tone.

Chang Lin: "..."

Living Lang: "..."

Fortunately, Chang Lin had already driven all the little eunuchs away with ease.

"Tell me." Li Shimin didn't care.

"The trade with Sasanian Persia can be done privately in the name of commerce. This matter should not be known to the outside world." Li Ke said straightforwardly, "Also, my Tang Dynasty will vigorously develop the marine industry, and All the shipbuilding technology of the Tang Dynasty is strictly forbidden to spread to the outside world, and those who violate it will be punished by the nine clans."

For the first time, Li Ke spit out very harsh words.

The expressions of Li Shimin and Li Chengqian became serious, and Chang Lin and Qijulang were numb. You must know that Li Ke never said anything about Zhu Jiuzu when he said that Li Shimin should give up his rights, but now Li Ke did.

"Your Majesty, Your Highness...how about we leave first?" Si Jilang who was sitting there hesitated for a moment, but he still spoke.

"No, you need to record these, it will be useful later." Li Ke directly stopped Qi Jilang's movements.

Living Lang: "..."

What else can he say, he can only sit here honestly.

"Why do you say that?" Li Shimin asked.

"Father, you know that the main material transportation between my Xizhou and Chang'an is from the Yellow River Basin, and the ships in the river are very important, so I spent a lot of money to let my people improve the ships."

"The current inland river transport ships have improved two very good ships, as well as more advanced sails, so that the speed of ships between Chang'an and Xizhou is faster! From this aspect, it can be seen that the river transport is very important. The importance of Datang."

Li Ke clicked on the Sui and Tang Grand Canal marked on the map. The Grand Canal dug by Li Ke’s cheap grandfather is not the Beijing-Hangzhou Grand Canal of later generations. The Beijing-Hangzhou Grand Canal of later generations was built by later dynasties. The Grand Canal dug by the emperor started from Chang'an, together with the Weihe River to the Yellow River, and then went down the Yellow River to the lower reaches of Luoyang, where it was divided into two parts, with one going north to Youzhou Zhuojun and Fanyang Commanderies (later Beijing).

The other one is to use Honggou and Hanhangou to extend to Hangzhou in later generations, which is now Qiantang County in the Tang Dynasty.

What is the gap?The gap is the famous Chuhe-Han Realm!However, the word "chasm" has since become an adjective. In fact, the chasm is an artificial canal dug in the Spring and Autumn Period and the Warring States Period.

In fact, it was only after this era that Li Ke could understand how wise the ancient Chinese were. The shock from culture, the deeper the understanding, the more numb the scalp.

Many things are traceable in history.

For example, the Zheng family of Xingyang!Why Xingyang?Instead of Nanyang, Pingyang, Anyang and so on?

Because during the Spring and Autumn Period and the Warring States Period, the gap between Jishui, Rushui, Huaishui, and Surabaya was connected, and the Yellow River met in Xingyang!And Xingyang has been an important river channel in the north and south of the artificial canal since the Spring and Autumn Period and the Warring States Period!

That's why it's Xingyang Zheng's!

Although the gap in later generations has already changed, only part of the river has been preserved for future generations to look up to!But in this era, it has an extremely important role. According to the actual exploration of Datang and the information learned by Li Ke, if the gap is calculated according to the data of later generations, the flat-bottomed boat can travel at least a thousand-ton ship!

There is no need for Li Ke to go into too much detail on how much material a thousand-ton wooden boat can pull. Of course, Datang cannot build such a large wooden sailboat.

"And shipping! Equally important!" Li Ke took a deep breath and directly clicked two places on the map.

One is the Southeast Asian peninsula of later generations, that is, Vietnam and other places.

"The land in this place is fertile and the climate is pleasant. Rice can be harvested three times a year. If we get some improved rice seeds from our Great Tang, the grain that can be produced here is more than enough to feed three Great Tangs."

"And these grains are extremely cheap in the local area. We can rely on convenient sea ships to transport them directly from this place, then pass through the Yangtze River or the Yellow River, and then transport them to various places in Datang through canals." Gestures.

And the living man next to him was quickly recording Li Ke's words.

Li Shimin and Li Chengqian were a little excited when they saw it, and they naturally knew how valuable it was.

"The point is that these places admire my Tang Dynasty very much. For example, the silk, cloth, porcelain, and tea of ​​my Tang Dynasty can be sold here at a price that is at least four to five times higher than that of Datang. Datang buys grain at one-third, or even one-fifth, and sends it back to Datang, and Datang can completely solve the grain problem." Li Ke first came to an example.

I didn’t mention other things at all immediately. There are many good things in Southeast Asia. The rubber and lacquer trees that are ready to be loaded in the back are relatively expensive things in Datang. Chinese medicinal materials.

And in places like the Philippines...and gold!A gold mine where dog head gold can appear!

"This river." Li Ke scratched on the map. This is the Mekong River in later generations, which is called the Lancang River in China. "I named it the Lancang River."

Li Ke domineeringly rowed out the entire river and said, "If we in the Tang Dynasty solve the problems in Tubo, Nanzhao and other places, we will use the improved Wanhu hu boats (hu, Tang volume unit) ) into this river, and with the basin area of ​​this river, we can control all the land on both sides of the river."

Converting the Wanhu ship, it is about a modern ship with a displacement of 600 tons. This displacement was already very abnormal in ancient times.