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[2. Modern means of transportation. 】

[10, boat. 】

[Ship or ship" refers to a means of transportation that uses the buoyancy of water to pull, pull, push, row, or push propellers and high-pressure nozzles by using the buoyancy of water, relying on manpower, sails, engines (such as steam engines, gas turbines, diesel engines, nuclear power units) and other power. 】

[In addition, civilian ships are usually called ships (ancient known as boats), ships, engines, and boats, military ships are called ships (ancient names are ships), ships, and small ships are called boats, sampans, rafts or boats, which are collectively called ships. 】

[On the earth, where human beings live, the area of the ocean accounts for 70.8% of the total area.] 】

[The total area of the Earth is about 510.072 million square kilometers, of which about 29.2% (148.94 million square kilometers) is land, and the remaining 70.8% (361.132 million square kilometers) is water.] 】

It is such natural conditions that have prompted the emergence and development of ships. 】

The development of the ship has gone through four eras: the age of the boat, the age of sailing ships, the age of steam engine ships and the era of diesel engine ships. 】

[1. The era of boats and rafts. 】

[In ancient times, the ancestors of human beings were still in the period of gathering and fishing and hunting, and the places of their 580 activities were forests, grasslands, rivers, and lakes. 】

[Due to the lack of water tools, schools of fish in deep water are out of reach. 】

[The beasts on the other side of the river are visible but not hunted. 】

[When the flood hits, you have to drown if you don't have time to escape. 】

[They have grown their talents and wisdom in the long struggle against the heavens and the beasts of the flood. 】

[Natural phenomena have inspired them in all sorts of beneficial ways. "The ancient view of fallen leaves as a boat" reflects our ancestors' early understanding that some objects can float on the water. 】

[Perhaps it is precisely because of this natural phenomenon that people have the idea of sailing.] 】

[A person can float down the river by sitting on a log, and if he is holding a piece of wood, he can paddle forward.] If the log is hollowed out, one can sit comfortably in it and carry one's belongings with them. This is the earliest boat that people created – the canoe. 】

[Later, people gradually learned to use local materials and made simple, stable rafts with large loading areas. 】

There are many types of rafts, including rafts, bamboo rafts, rafts, etc. 】

[The appearance of canoes and rafts in primitive societies made mankind take an important step in the struggle to conquer rivers. 】

[Following the weaving of wood for rafts, there is also "gourd wood for boats" ("Zhou Yi Dictionaries"). 】

["Kua" means to cut and hollow out, and "boat" refers to the direct ancestor of ancient ships - canoes. 】

[With a boat, people can't move freely in the water, and they must also have tools to propel the canoe forward.] 】

["Wood for the Tree" ("Zhou Yi Dictionary"), that is, refers to the method of making oars by the ancients, and "carving" means cutting. "Ji, Jieye, dial the water to make the boat swift" ("Release the Name and Release the Boat"). 】

[Sharpen the wood to make an oar and propel the boat forward.] 】

[People can move more freely on the water.] 】

[It is not yet possible to determine the exact era of the appearance of the canoe. 】

[But in 1977, in the Neolithic site of Yuhe Mudu in Zhejiang, a wooden paddle was unearthed "carved" from the whole wood. 】

[It shows that at the latest about 7,000 years ago, the use of canoes in China began.] 】

[At the same time, it also shows that the history of the invention and use of boats in China is thousands of years earlier than the era of the emergence of chariots and horses. 】

[The shape of the ancient canoe in China is roughly three: one is square with a head and tail, not warped, and connected to the bottom; one is a square head and tail, and the head and tail are warped; and the head and tail are pointed, and both ends are warped. 】

[The advantage of the canoe is that it is a "du" word, the boat body is integrated, strict and seamless, not easy to leak (beaj) water, will not be loose, and the production process is simple, so the history of use is very long, until today, in the southwest minority areas of our country, the canoe is also used as a tool for crossing the river. 】

[The emergence of rafts and canoes was the first step taken by mankind to open up water transportation. 】

[With them, the range of human activities has expanded from land to water, and human beings can cross rivers from now on, so that the territorial barrier has lost its original power. 】

【......】

"The ocean accounts for seventy percent of the land we live in??"

"It's unbelievable, beyond the land, there is no ocean!"

"It's no wonder that when a fishing boat gets lost in the sea, it doesn't hear from you, because the land is too small. "

“..."

The ancients never measured the area of the sea.

This will see the detailed data of light curtain science, and it is also surprising.

Qin Dynasty.

Ying Zheng was slightly distracted.

He hurriedly asked people to bring the previous world map. (If you read a violent novel, go to Feilu Novel Network!)

"Except for the land, such a large blue area is all the sea. "

He roughly estimated the proportion of the ocean, and found that it was roughly 70%!

And many lands are not connected to each other, separated by endless seas.

This made him desperate to develop ships.

Ming dynasty.

Zhu Di recalled what he had learned before, and suddenly thought of a poem that was very appropriate.

"If you don't accumulate steps, you can't reach thousands of miles, and if you don't accumulate small streams, you can't become rivers and seas." "

"Without the accumulation of ancestors, how could the Ming Dynasty achieve the feat of going to the West. "

His father, Zhu Yuanzhang, did not have developed shipbuilding technology when he was at war with Chen Youliang, so he could only have small fishing boats.

I've been haunted by this.

After the establishment of the Ming Dynasty, it vigorously developed shipbuilding technology.

And the advanced shipbuilding technology that Zhu Yuanzhang understands is big!

The bigger the ship, the more advanced the shipbuilding technology.

In this way, there was a large fleet when Zheng He went to the West. []